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FREYTAG, Paul Harold, 1934- A REVISION OF THE NEARCTIC SPECIES OF THE GENUS IDIOCERUS (HOMOPTERA, CICADELLIDAE, IDIOCERINAE).

The Ohio State University, Ph.D., 1963' Zoology \ University Microfilms, Inc., Ann Arbor, Michigan A REVISION OF THE NEARCTIC SPECIES OF

THE GENUS IDIOCERUS (HOMOPTERA, CICADELLIDAE, IDIOCERINAE)

DISSERTATION

Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University

By

Paul Harold Freytag, B. S., M. Sc.

The Ohio State University 1963

Approved by

JT Adviser Department of Zoology/ and Entomology ACKNOWLEDGMENTS

I am greatly indebted to my adviser, Dr. D. M. DeLong, for his supervision of this study, for the loan of his personal collection

Including his type material, and for making it possible to examine other collections both in this country and in Europe. Many helpful suggestions were also appreciated from other members of The Ohio

State University faculty and students, these too numerous to list individually.

I also wish to express my sincere appreciation to the following persons for the loan of their institutions' collection or for making their material available for study: P. A. Lawson of Colorado State

University; P. P. Burbutis of the University of Delaware; P. W, Mead of the State Plant Board of Florida; W. P. Barr of the University of

Idaho; H. H. Ross of the Illinois Natural History Survey; G. W. Byers of the University of Kansas; D. A. Young and H. D. Blocker at the

North Carolina State College; J.N. Knoll and C. A. Triplehorn of

The Ohio State University; D. A. Donley of the U. S. D. A. Forest

Service Research Laboratory, Delaware, Ohio; P. W. Oman of the United

States Natural History Museum; W. D. Fronk of the University of

Wyoming; W. E. China and R. J. Izzard of the British Museum of Natural

History; and M. Beier of the Naturhistorisches Museum, Vienna, Austria.

ii For many of the plant identifications I am indebted to C. L.

Porter of the Rocky Mountain Herberiam, University of Iffyoming and

G. W, Argus of the University of Saskatchewan. Without their help the host plants of many of the species would still be unknown.

iii TABLE OF CONTENTS

Page

ACKNOWLEDGEMENTS ------.------ii

LIST OF C H A R T ------v

LIST OF ILLUSTRATIONS------• ------vi

INTRODUCTION ------.------1

ECONOMIC IMPORTANCE------: - 2

DISTRIBUTION AND HOST PLANTS------U

PARASITES ------. --.------.------6

MATERIALS AND METHODS ------8

MORPHOLOGY AND' TERMINOLOGY ------10

TAXONOMIC PROBLEMS ------13

PHYLOGENY ------15

TAXONOMY OF THE G E N U S ------19

KEY TO THE SPECIES (MALES O N L Y ) ------.------22

DESCRIPTIONS OF THE S P E C I E S ------29

INDEX TO LDIOCERUS SPECIES------119

APPENDIX------125

BIBLIOGRAPHY------126

AUTOBIOGRAPHY------155

iv CHART

Chart Page

I Phylogeny of Nearctic Idiocerus, ------18

v LIST OF ILLUSTRATIONS

Figure Page

1-8 General External Morphology and Terminology. - — 135

9-56 Ventral and Lateral View of the Aedeagus of

Various Species of Idiocerus. - - - — - - - - 137

57-101* Lateroventral View of the Style of Various

Species of Idiocerus, ------lip.

105-152 Ventral View of the Connective, of Various

Species of Idiocerus. - — - — — - — - - 1U3

153-200 Lateral View of the Pygofer and Plate of

Various Species of Idiocerus.------11*5

201-21*7 Ventral View of the Female Genitalia of

Various Species of Idiocerus. - - — - - — - ll*9

vi INTRODUCTION

This study is the first attempt to revise the classification of all the known species of the genus Idiocerus for the Nearctic region.

More than half of the described species are known only from the original descriptions, and most of these were based entirely on the external morphology and color patterns. Through a study of the male genitalia, first used in this group by DeLong (19U7) and Oman (19U7),

a much clearer understanding of the species and their relationships to each other is obtained. The external genitalia and the seventh

sternum of the female were also found to be valuable characters where closely related species had quite similar male genitalia.

Further studies utilizing these and additional characters will undoubtedly add many more species to the ones which are covered in

this revision.

1 ECONOMIC IMPORTANCE

Most of the Nearctic species of Idiocerus occur on poplars and willows and are therefore relatively unimportant as economic pests.

There are, however, a few species which have been considered pests of trees in orchards and nurseries.

One species,-Idiocerus fitchi, has been -reported by Brittain

(1915), Brittain and Saunders (1917), and DeLong (1931) as attacking and damaging apple trees. This species along with I. provancheri are known to occur commonly on apple trees in Eastern North America, but the latter species is not known to be abundant enough to cause noticeable damage to trees.

Many species of the genus are likely pests on nursery stock or young trees in yards. Weiss (1918) reported that I. cognatus was a pest on white poplar nursery stock. All the Idiocerus species which were introduced from Europe were seemingly brought over to this continent by such infested nursery stock.

No member of the genus has been reported as a vector of a plant virus,.but the possibility is still great that they are also vectors of virus diseases. The damage done to the plant is seemingly from the sucking of the plant sap or from the punctures in the plant at the time of oviposition. The high rate of parasitism found in this genus is probably a great factor in keeping the numbers of individuals below the economic level. DISTRIBUTION AND HOST PLANTS

The genus Idiocerus In the broad sense Is cosmopolitan In distribution. As I have described the genus in this study it will be evident that most of the species now described for the Holarctic region belong to this genus while most of the species outside this region should be transferred to other genera. However, a generic revision of the subfamily Idiocerinae is needed before the true range of the genus is understood.

Many of the species have a very wide range of host plants, while others seem to be limited to a single host plant. Very little of this

type of data has been recorded, and of that which has been much is

unreliable. During the course of this study, a large series of

specimens collected from willow and poplar by Dr. H. H. Ross, in the

Illinois Natural History Survey Collection, and many specimens I have

personally collected have greatly increased our knowledge of this host

plant relationship. The plants which were identified are either in

the Illinois Natural History Survey Collection or the Rocky Mountain

Herbarium, Laramie, Vfyoming.

The Nearctic species of Idiocerus occur mostly on trees and

shrubs, with the majority of the species on members of the family

Salicaceae (Salix spp, and Populus spp.). Other species occur on genera such asj Crataegus. Junlperus. Ribes. Quercus. Chrysothamnus.

Salsola. Pyrus (subgenera Malus and Aronia). Ulmas. Plcea, Rhus.

Sequoia, gymenoclea. Pluchea, Grossularia, Taaodium, Alnus. and

Libocadrus. PARASITES

The adult leafhoppers were found to be parasitized by all three major groups reported by Oman (19U9), namely Dryinldae (Hymenoptera),

Pipunculldae (Diptera), and Halictophagidae (Strepsiptera) • The

Dryinids and Halictophagids are fairly common parasites of Idiocerus while Pipunculids are rarely found*

All three groups of parasites cause a modification of the genitalic structures, in particular, the reduction in size and shape of the aedeagal apodeme and the apodeme of the styles* This effect can be seen in the style of obstinatus (fig. 71) as every male

specimen of this species examined was parasitized. Another indication of damage by the parasites is the reduction or absence of the large

internal apodemes of the first, second, and third abdominal segments.

This type of damage was reported by Ross and Moore (1957) in Bnpoasca

as having the effect of preventing the development of these structures

so greatly that they may be entirely different from the shape found

in normal members of the same species.

In several species, such as apache, couleanus, and femoratus,

another effect of parasitization seems to be present. Male specimens

have been found which have, instead of the normal male color pattern,

the color pattern of the female. In all such specimens, which were dissected, they were fdund to be parasitized by Pipunculids. This type of male dimorphism has caused some confussion in the classifi­ cation of the species of this genus. No similar affect has been found in parasitized females of the same species.

The percentage of parasitization varies greatly from none to a rather high rate of approximately 80 percent. The rate of parasiti­ zation also seems to be higher in the West than in the East, and varies from year to year* A typical example of a high amount of parasitization is a series of 10 specimens (1* males and 6 females) of rotundens collected by Ross and Smith near Paris, Illinois on

September 26, 1958* Of the 10 specimens only 3 (2 males and 1 female) were unparasitized. The rest of the specimens were parasitized as follows: 1 female with 1 Strepsipteran, 1 male with

2 Strepsipterans, 1.female with 1 Strepsipteran and 1 Bryinid.,1 male with 1 Strepsipteran and 2 Dryinids, 2 females with 1 Dryinid each,

and 1 female with 3 Dryinids. MATERIALS AND METHODS

Approximately 20,000 specimens were examined during the course of this study. These were representative of nearly every part of the

United States and Canada, and some parts of Mexico. European specimens were also examined where there was any possibility that the species had been introduced into the Nearctic region*

The methods of studying the male genital structures as outlined by Oman (19U?) were followed, with only slight exceptions. The whole abdomen was removed by inserting an insect pin between the thorax and abdomen. The abdomen was then placed in a microdish and -a solution of 10-percent potassium hydroxide was added. This was left standing, not heated, for approximately one-half to one hour or until the proper clearing was obtained. The abdominal contents were then expelled by lightly pressing on the abdomen with the head of an insect pin. The potassium hydroxide was than removed and replaced by water. The abdomen was again lightly pressed to expel any remaining contents and to wash away the potassium hydroxide. After another such wash the water was replaced with glycerin and the specimen was ready for study.

All structures were left Intact unless a more detailed study warranted the dissection of the internal genitalia from the genital capsule. This was easily acconplished by the use of sharply pointed

8 insect pins. If removed they were placed along with the abdomen and genital capsule in a small stoppered vial containing a small amount of glycerin. This vial was placed back on the insect pin bearing the specimen by means of pinning obliquely through the cork of the vial.

A n measurements and drawings were made by using a binocular microscope equipped with a crosshatch micrometer reticule. MORPHOLOGY AND TERMINOLOGY

Several good publications on leafhoppers should be consulted for a detailed study of the morphology and terminology used in this family, such as Evans (19U7), Oman (I9l;9), Singh-Prathi (1929), and

Tuxen (1956). Here, only the structures used in the classification of the species of Idiocerus 'will be discussed.

The head, in dorsal view, (fig. 3) consists of the vertex (or crown of some authors) with the compound eyes on either side. The anterior margin of the vertex varies greatly in shape, sometimes i greatly produced as in productus but most generally rounded or nearly * rounded. The fore part of the head or face (fig. 2) consists mainly of the postclypeus, the anteclypeus, the lor a, and the genae. The shape, size, and color pattern of' these sclerites are often diagnostic. The male antennal discs (figs. 5 and 6) are very distinctive for the species which possess them.

The pronotum and scutellum (fig. 3) are quite uniform in shape throughout the genus. The color pattern, however, may be quite diagnostic and useful in separating species.

The venation of the forewing (fig. U) and hindwing was found to be relatively similar for all species and only a few differences occur. Some species have the outer anteapical cell rectangular,

10 others triangular, and others it is undeveloped, but so much variation occurs even -within a species that this was considered an unreliable character to separate species. Color patterns of the forewing were, however, helpful in separating many species.

Male Genitalia* The external genitalia (fig. 7) or ninth abdominal segment consists mainly of two lateral plates, continuous dor sally, and known as the pygofer. The pygofer may be modified with an internal spine on each of the lateral plates, such as in spinosus.

Ventral to the pygofer and articulated to it is a pair of plates or subgenital plates which are usually long thin processes margined with fine setae. The pygofer and the plates are collectively called the genital capsule. The eighth sternum is modified into a valve-like

structure, but this is probably not homologus with the valve of other groups of leafhqppers.

Within the genital capsule are the internal genitalia consisting of the aedeagus, the connective, and the paired styles. The aedeagus is basally articulated with the connective and consists of two rather distinct parts, the ventral part or aedeagal shaft and the dorsal part or aedeagal apodeme. The aedeagal shaft is tubular and traversed by the gonoduct. The gonoduct terminates ventrally at the gonopore usually near the apex of the aedeagal shaft. A pair of lateral spine­

like processes are also usually present near the gonopore. The

aedeagal apodeme is relatively large in this genus and serves as a place for muscle attachment.

The styles, which lie one on each side of the connective and 12 laterally articulated to it, are ventrally articulated to the plates.

The apical end of the style is curved distally and bearing a row of lateral hair-like spines along the side and usually with several large combined spines at the apex. The basal end of the style is an apodeme for muscle attachment.

The connective or central structure with which the aedeagus and styles articulate, is a relatively simple ”TW shaped or rectangular shaped piece with varies only slightly throughout the genus.

Female Genitalias The seventh sternum is variously shaped and usually possesses - either a median emargination or a produced median area. The pygofer is in the shape of a large plate-like process on each side of the ovipositor. The ovipositor is a long median structure consisting of the external sheath and the internal valvifers. The ovipositor extends beyond the pygofer and its length beyond the pygofer in relation to its own width was found to be diagnostic for many species. TAXONOMIC PROBLEMS

Many of the species of the genus are sexually dimorphic in both color pattern and certain morphological characters such as total body size and shape of the head and antennae. These sexual differences make it somewhat difficult to associate the male with the female of the same species. However., these dimorphic characters were found to be very helpful in separating species where the genitalia were nearly the same.

The problem of sexual dimorphism is further complicated by the effect of parasites, as discussed earlier under that heading. This type of dimorphism is still not fully understood, but seems to occur only in the males of several species closely related to I. altematus.

Specimens so parasitized are very difficult to place to species, and have caused a great amount of confusion in the taxonomy of the genus.

Parasitized specimens, in general, were avoided where possible in the following classification, as the genitalic characters are almost always distorted or deformed, Teneral forms are also commonly encountered, and were also avoided where possible as the color pattern was undeveloped and the genitalia distorted and shriveled.

Seasonal differences in the color pattern were also encountered but were less confusing as the pattern remained the same although the

13 color changed. There were also many slight differences due to the geographical region or elevation from which the specimens were collected. In most cases these slight differences were ignored as the male genitalia were the main criterion for separating these species. PHYLOGENY

On the basis of the male genitalia, it is possible to arrange the species of Idiocerus into two major divisions. The first major

division is characterized by having the lateral spines of the style

either uniform in both size and spacing or reduced. The type of

style, where the spines are uniform in size and spacing is seemingly

the primitive condition of this structure. The other major division

contains species which have the spines on the style modified, in

that the apical spines are grouped at the apex and greatly enlarged.

The first major division can be subdivided into six species

groups on the basis of the aedeagus. Two of these species groups,

the dolosus group and the fitchi group, have an aedeagus without

processes on the shaft, while the other four species groups, the

cognatus group, the ramentosus group, the snowi group, and the

decimusquartus group, have processes on the aedeagal shaft. There

is one species, moniliferae. which is an exception to this as it is

being assigned to the cognatus group even though it lacks the

processes on the aedeagal shaft. This species may represent a

separate line of development by itself, but is placed in the cognatus

group on another genitalic character as mentioned later under the

discussion of this species group. 1 6 The dolosus group contains three Nearctic species which are all very closely related. The most primitive member appears to be dolosus as the pygofer spine, which is found in -this group, is undeveloped.

The fitchi group contains two species, fitchi and provancheri, which are very closely related genitalic ally, but seemingly quite separate from the other species groups.

The cognatus group contains four Nearctic speciesj three possibly introduced to this region from the Palarctic region, and one, moniliferae. which is native to this region. This species group is characterized by having the plates thickened nearly to the apex.

The ramentosus group contains two species, ramentosus and crataegi, which are quite divergent in many respects, but are related in that they possess a very similar type of plate and pygofer. These two species seem to have come frbm^tK^same line of development, but became separated very early.

The snowi group contains only one species, snowi, and its true placement is uncertain as there are no close relatives to it.

The decimusquartus group is a Palarctic group and is represented in the Nearctic region by one species, declmusquartus. This species has many primitive characteristics and may represent the ancestral form of this genus.

The second major division is divided into three fairly distinct species groups. The first species group, the pallidus group, has the ' aedeagal shaft tubular right up to the apex, while the other two species groups, the alternatus group and the stigmaticalis group, have 17 the aedeagal shaft modified into a flattened area at the apex.

The pallidus group contains eight Nearctic species which are all very closely related. This species group probably represents a section of the populi group of the Palarctic region, and would indicate a dispersal from that region at a very early time.

The stigmaticalis group is a Palarctic group and one species, stigmaticalis, is known in the Nearctic region. This species group

is characterized by having the gonopore basal to the processes of the aedeagal shaft.

The altematus group is the largest species group in the Nearctic region, and contains the remaining 27 species. This species group is

characterized by having the gonopore apical to the processes of the

aedeagal shaft. The different branches within this species group are based on many small genitalic differences, and only represents one possibility as to the relationship of these species.

A graphic arrangement of the possible evolution of the Nearctic

species, as briefly stated above, is shown in chart I. axilus 13 catalinus rotandcns apache morosus alternntus tahotus distinctus omani ensiger femoratus couleanus obstinatus subnitcns productus concinnus pyramidatus texanus depictus arooenus balli taxodium nervatus rossi delongi obispanus musteus

stigmaticalis

suturalis vagus perplexus W CO pallidus duzeei formosus lachrymalis maximus

decimusquartus

snowi ramentosus crataegi cognatus ruf us fc2 O cinctus moniliferae fitchi provancheri dolosus chisosus spinosus Chart I.-- i'hylogeny of Nearctic Idiocerus TAXONOMY OF THE GENUS

The genus Idiocerus was erected by Lewis in I83I* for a single species Idiocerus stigmatical-Vg, The overall body shape, including the position of the frontal sutures in relation to the ocelli and the unusual antennal discs of the male, separated this species from all other described groups. As new species were found and added to the genus it became apparent that many of the species were differently shaped and lacked the male antennal discs. Through a study of many species from different parts of the world it is now my opinion that the male genital structures offer many more reliable characters than do the external characters. If the genital characters are used,

Idiocerus is restricted to the species which have the aedeagal apodeme well developed, styles long and arched, and the plates long and relatively narrow.

The genus Zinneca Amyot and Serville, 181*3, is considered a

synonym of Idiocerus by Evans (191*7), but I prefer, at the present time, to follow Oman (191*9) in considering this a Neotropical group.

Since its erection Idiocerus has been placed in several different

subfamilies by different workers. It was first placed in the

Bythoscopinae by such workers as DeLong (1916) and Osborn (1928), then placed in the Euryraelinae by Medler (19l*2) and DeLong (191*8),

19 20 and then into Idiocerinae by Evans (19U7), Oman (I9h9), Ribaut

(1952), and Beirne (1956).

Idiocerus Levis

Idiocerus Levis, I83U, Trans. Ent. Soc. London l:h7.

Type by monotypy, Idiocerus stigmaticalis Levis, 183U.

Wedge shaped leafhoppers. Head vider than pronotum, vertex short and usually broadly rounded vith median length equal to or less than length near eyes. Male antennae vith or without an expanded disc. Pronotum broad, vith lateral margins rounded.

Scutellum triangular. Foreving flaring, longer than abdomen, vith a large appendix.

Ovipositor of female extending beyond pygofer. Pygofer long and rounded. Seventh sternum about twice as vide as long, vith posterior margin straight, produced, or medially emarginate.

Male plates long, narrow to slightly thickened, and margined vith fine setae. Pygofers variously shaped. Styles long, slender, curved, and usually bearing a row of fine lateral setae and several large combined spines at apex. Aedeagus vith a tubular recurved shaft bearing an apical or ventral gonopore, and with a well developed dorsal apoderae. 21

Oman (19U9) listed 87 names for the Nearctic species of

Idiocerus. with a total of 71 valid species. In this study 98 names are listed, of which 7 are new species and 29 are new

synonyms, totaling $0 valid species. One old species, I. striolus.

is treated as a nomen dubium (see Appendix). KEY TO THE SPECIES

(MALES OHLY)

1 Aedeagal shaft without processes (Pig. 9 ) . ------2

1* Aedeagal shaft with processes (Fig. 111). ------7

2 . (1) Plates thickened nearly to apex (Fig. 163).- - moniljferae

2* Plates thin to base (Fig. 1 6 7 ) ------— 3

3 (2 *) Pygofer broadly rounded at apex, with or without

an internal spine-like process (Fig. 158). - - - a

3' Pygofer not rounded at apex, without an internal

spine-like process. (Fig. 155). ------: 6 h (3) Apex of aedeagal shaft spatulate (Fig. 11).- - - - dolosus

Apex of aedeagal shaft pointed (Fig. 1 2 ) . ------5 U* *

5 (U') Gonopore near middle of aedeagal shaft (Fig. 12), and

a well developed spine-like process on pygofer.- - spinosus

S’ Gonopore closer to apex (Fig. 13), and a shorter spine-like process on pygofer. ------ohisosus

6 (3*) Aedeagal shaft with gonopore near apex (Fig. 10).------

. . . provancheri

6* Aedeagal shaft with gonopore a third the length

of the shaft from apex (Fig. 9 ) . ------fitchi

22 23

7 (l1) Processes of aedeagal shaft near the middle (Fig. 16). 8

7 ‘ Processes of aedeagal shaft near the apex (Fig. 15). - 9

8 (7) Gonopore some distance from the processes of the

aedeagal shaft (Fig. 16).------decimusquartus

8* Gonopore near the processes of the aedeaLgal shaft

(Fig. 17). ------snowi

9 (71) Processes of aedeagal shaft setaceous (Fig. 15). crataegi

9 1 Processes of aedeagal shaft not setaceous (Fig. lU). - 10

10 (9') Style without large apical spines (Fig. 69).--- — 11

10* Style with large apical spines (Fig. 76).------lU

11 (10) Plates large, thickened nearly to apex (Fig. 166). - - 12

11’ Plates small, thin to base (Fig. 153). ramentosus

12 (11) Apex of plates narrow and nearly pointed (Fig. l6l»). - - -

------— cognatus

12* Apex of plates wide and rounded (Fig. 165).------13

13 (12') Dorsal expansion of aedeagal apodeme extending nearly

to the base of the aedeagus (Fig. 20). - - - — - - rufus

13' Dorsal expansion of aedeagal apodeme extending about

half way to the base of the aedeagus (Fig. 21).- - cinctus

111 (10*) Costal margin of forewing with an asperate area. - - - - -

------— - stigmaticalis l U 1 Costal margin of forewing smooth.------15 2U l£ (iu«) Aedeagal shaft tubular at apex (Fig. 23).- - - - - — 16

15' Aedeagal shaft flattened at the apex (Fig. 38).------23

16 (l£) Vertex with definite round black spots on the margin* 17

16' Vertex without definite round black spots on the

margin, but nearly unicolorus.------1?

17 (16) Forewings almost evenly gray colored.- lachrymalis

17' Forewings darkly marked.------18

18 (171) Large, total body length over 6 m m . ------maxlmus

18* Smaller, total body length under 5 mm. — - — formosus

19 (16') Color uniformly yellow, without dark markings. - - - - 20

19' Color yellow or orange, with dark markings.------21

20 (19) Processes of aedeagal shaft short (Fig. 23). - - pallidus

20* Processes of aedeagal shaft long (Fig. 27).- - - perplexus

21 (19') Processes of aedeagal shaft short (Fig. 2h). - - - duzeei

21* Processes of aedeagal shaft long (Fig. 25).------22

22 (21*) Processes of aedeagal shaft setaceous and straight

(Fig. 2 6 ) . ------suturalis

22' Processes of aedeagal shaft thicker and curved

(Fig. 2$).------vagus

23 (151) Eighth sternum deeply excavated leaving the

lateral portions long and pointed (Fig. 7).— - - -apache 25

23' Eighth sternum not deeply excavated, lateral portions

short and rounded.------— 2U

2U (23*) Vertex greatly produced, with a median dark spot.- - -

------productus

2l*» Vertex not produced, usually evenly rounded. - - — - 25

25 (2U1) Middle femora greatly enlarged.- femoratus

25' Middle femora nearly the same size as the others.- - - 26

26 (25') Gonopore at the apex of the aedeagal shaft (Fig. 28).- 27

26* Gonopore subapical and on the ventral surface of the

aedeagal shaft (Fig. UO).------29

27 (26) Processes of the aedeagal shaft long and thin

(Fig. 28). ----■■----- delongi

27’ Processes of the aedeagal shaft short and thick

(Fig. 2 2 ) ...... 28

28 (27’) Antennal disc inconspicuous or lacking, face

unmarked or lightly marked above ocelli.------musteus

28' Antennal disc large, face mostly patterned with

black. ------obispanus

29 (261) Plates over 1 mm. in length, with a narrow base

(Fig. 181).- - - — ------couleanus

29' Plates 1 ram. or less, never shaped as above. ------30

30 (2 9 *) Vertex with dark markings or distinct spots. - - - — 31 26

30' Vertex without markings, at most, with very small

spots; mostly unicolorus green or yellow orange. ---- Ul

31 (30) Forewings definitely banded. ------32

31* Forewings variously patterned, but not banded. 33

32 (31) Style with a single spine at the apex (Fig. 100)*— - - -

------distinctus

32* ' Style with several combined spines at the apex

(Fig. 9 0 ) . ----- tahotus

33 (31*) Large, total body length over 5 mm., with a dark

spot in the middle of the vertex.- - subnitens

33 • Mostly under 5 mm. in length, but if over 5 mm.

not marked as above. - - — - 3U

3h (33*) Face with a dark band down the median line.- - obstinatus

3U1 Face not marked as above.------35

35 (3U1) Face with lora margined on each side with black. 36

351 Face variously patterned but never with black

margins on lora. ------37

36 (35) Antennal discs small and inconspicuous.- - - - alteraatus

36' Antennal discs large and prominent.------raorosus

37 (35*) Aedeagus very short, a third of a mm. or less. - - - - 38

37’ Aedeagus longer, over a third of a m m . ------39 27

38 (37) Antennal discs nearly same length as width.- - - catalinus

38' Antennal discs much longer than wide.------exilus

39 ( 37') Small species with large spots on the vertex and

large round antennal discs (Fig. 6). ------rotundens

3 9 ’ Larger species not marked as above.------Uo

UO (39*) Apex of style pointed (Fig. 91), antennal discs

long and narrow* ------— ------ensiger

UO1 Apex of style blunt (Fig, 8U), antennal discs short

and narrow.------omani

Ul (30’) Forewings unicolorus yellow or green.------U2

Ul' Forewings yellow to orange yellow with a faint pattern,

nearly always with a clear spot at apex of clavus. - - UU

U2 (Ul) Antennal disc large, globular, wrinkled, and brown. -

- - rossi

U2* Antennal disc not as above.------U3

U3 (U21) Antennal disc small, round, and near the apex of

the antennae.------nervatus

1*31 Antennal disc elongate, constricted at both ends, and

at some distance from the apex of the antennae,- taxodium

UU (Ul1) Large, total body length ofer 5,1 mm,------U5

UU' Smaller, total body length under 5 m m , ------— U6 28 k$ (IUj.) Postclypeus with a median orange stripe; apex of

pygofer rounded (Fig. 190).------concinnus

U51 Postclypeus unicolorus; apex of pygofer nearly

pointed (Fig. 189).------pyramidatus

U6 (UU') Apex of style deeply excavated (Fig. 95).------ball!

W ’ Apex of style either pointed or blunt. ------U7

U7 (U6 1) Pronotum yellow with orange patches; apex of style

blunt (Fig. 9 6 ). ------amoenus

U7f Pronotum unicolorus; apex of style pointed or

nearly so (Fig. 9 3 ) . ------U8

I48 (147’) Forewings nearly banded with brown; apex of style

thin and pointed (Fig. 93).------depictus

148* Forewings unicolorus yellow orange, except for

the clear spot at the apex of clavus; apex of

style thick and pointed (Fig. 9U). ------texanus DESCRIPTIONS OF THE SPECIES

Idiocerus provancheri Van Duzee

(Figs. 10, 57, 109, 155, and 2 0 6 )

Bytho scopus clitellarius Provancher, 1890, p. 288. Name preoccupied.

Idiocerus provancheri Van Duzee, 1890, p. 1.1.1; Osborn and Ball, I898,

p. 127j Osborn, 1905, p. 507; Leonard, 1915, p* Ul5;

Lawson, 1920, p. 6U; DeLong, 1923, p. 65; Osborn, 1928,

p. 213; Medler, 191*2, p. 11; DeLong, 191*8, p. 120; Beirne,

1956, p. 26.

A reddish brown species with yellow markings. Length: Male

U.8 to 5.7 mm, female 5*1 to 6.2 mm. Width of head: Male 1.7 to

1.8 mm, female 1.7 to 2.1 ram.

Vertex evenly rounded, same length in middle as near eyes.

Postclypeus longer than wide; anteclypeus longer than wide, with an expanded apex. Male antennae .simple, without disc. Forewing long, straight sided, with a very large appendix.

Color.-- Vertex yellow with two large black spots about their own width from eyes. Face of male yellow with a brown stripe down the median line. Face of female mostly brown with a yellow spot beneath each ocellus. Pronotum and scutellum mostly yellow brown,

29 30 but sometimes males entirely black. Forewing mostly brown with a yellow streak at base of clavus and a clear area near apex of outer anteapical cell.

Male genitalia.-- Plate long, narrow, truncate at apex. Pygofer pointed terminally, with a small median expansion on ventral side.

Style curved, tapered to a pointed apex which has a raised asperate area. Connective thickened, shape of an inverted BTn, with a wide median ventral projection. Aedeagus with shaft narrowing to a flattened apex, without processes, gonopore near apex on ventral surface; apodeme expanded at apex, with a small dorsal expansion.

Female genitalia.— Ovipositor long, extending about its own width beyond pygofer. Pygofer long, unevenly rounded. Posterior margin of seventh sternum produced with a median emargination.

Host plants.— This species has been collected on Crataegus.

Pyrus (subgenera Malus and Aronia only), Picea. and Ulmus.

Specimens have been reared from apple (Pyrus Malus L.) and hawthome

(Crataegus phaenopyrum (L.) Medic.).

Type.— Lectotype male from Buffalo, New York, June, 1887,

E. P. V. (Iowa State College Collection); designated by Oman (19U7).

Distribution of material examined.— United States: Arizona,

California, Colorado*, Idaho, Indiana, Iowa, Kentucky, Maine,

Massachusetts, Michigan, Minnesota, Mississippi, Montana, New

Hampshire, New York, North Carolina, North Dakota, Ohio, Pennsylvania,

South Dakota, Utah, and Wisconsin. Canada: Albei-ta, British

Columbia, Manitoba, and Quebec.

Remarks.— A total of 196 specimens was examined. 31

Idiocerus fitchi Van Duzee

(Figs. 9, 65, 108, 15U, and 205)

Idiocerus maculipennis Bitch, 1851, p. 59; Osborn and Ball, 1898,

p. 73j Osborn, 1905, p. 507. Name preoccupied.

Idiocerus fitchi Van Duzee, 1909, p. 383; Lawson, 1920, p. 63; DeLong,

1923, p. 63; Osborn, 1928, p. 212j Medler, 19U2, p. 12*

DeLong, 19U8, p. 120; Beime, 1956, p. 26.

Resembling provancheri, but larger, slightly different color pattern, and distinctly different genitalia. Length: Male 5.U to

5.8 mm, female 5.7 to 6.2 mm. Width of head: Male 1.8 to 2.1 mm, female 1.9 to 2.2 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus longer than wide; anteclypeus longer than wide, with an expanded apex. Male antennae simple, without disc. Forewing long, straight sided, with a very large appendix.

Color.— Vertex yellow with two large black spots about their own width from eyes. Face of male yellow with a brown stripe down the median line. Face of female mostly yellow brown with,a yellow patch beneath each ocellus. Pronotum yellow with large spots of yellow brown and irregular brownish black spots on the anterior margin. Scutellum yellow with brownish black triangles. Forewing mostly brown with a yellow spot near apex of clavus and another near apex of outer anteapical cell. 32

Male genitalia.— Plate long, narrow, rounded at apex. Pygofer rounded with a small median expansion on ventral side. Style curved, tapering to a pointed apex which has an asperate area. Connective thickened, shape of an inverted “Tw with a broad median ventral projection. Aedeagus with a long shaft narrowing to a flattened apex, without processes, gonopore some distance from apex on ventral

surfacej apodeme expanded at apex, with a small dorsal expansion.

Female genitalia.-- Ovipositor long, extending about its own width beyond pygofer. Pygofer long, unevenly rounded. Posterior margin of seventh sternum evenly produced, without median

emargination.

Host plants.— This species has been collected on Crataegus.

Pyrus (subgenus Malus). and Ulmus.

T22e.- The type of this species was not seen and is presumably-

lost.

Distribution of material examined.— United States* Connecticut,

Illinois, Indiana, Iowa, Kansas, Maryland, Massachusetts, Mississippi,

Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, and

Wisconsin. Canada: Ontario.

Remarks.— A total of 122 specimens was examined. 33

Idiocerus declmusquartus (Schrank)

(Figs. 16, 67, 110, 156, and 216)

Cicada decimaquarta Schrank, 1776, p. 137.

Idiocerus dec imusquartus China, 1938, p. 191; Ribaut, 1952, p. 366j

Beirne, 1956, p. 25.

Jassus scurra Germar, 183U, pi. 11.

Idiocerus scurra Melichar, 1 896, p. l5lj DeLong, 1923, p. 65j Buys,

192li, p. liij Osborn, 1928, p. 212.

Idiocerus scurrus DeLong, 19^8, p. U 8 .

Jassus crenatus Germar, I83U, pi. 10.

Bythoscopus crenatus Kirschbaum, 1868, p. 166.

Idiocerus germari Fieber, 1868, p. U5l

Idiocerus gemnd.sjjnal.ans Leonard and Crosby, 1915, p. 5U2.

A large robust species generally olive brown with darker brown markings on head and pronotum. Length} Male 6.1 to 6.8 mm, female

6,7 to 7.7 mm. Width of head: Male 2.3 to 2.7 mm, female 2.6 to 3.0 mm.

Vertex rounded and very slightly produced in middle, little

longer near eyes than in middle. Postclypeus broadly rounded, wider

than long; anteclypeus longer than wide, not expanded at apex.

Male antennae simple, without disc. Forewing flaring, appendix of

moderate size. Color*— Head and pronotum olive brown, with irregular brown markings. Scutellum olive brown with dark brown triangles and brown markings near median line. Forewing olive brown, venation yellow interrupted with brown.

Male genitalia.— Plate long, narrow, expanded apically, longer than pygofer. Pygofer rounded terminally, with a rounded ventral expansion. Style narrow, curved near apex which is somewhat expanded.

Connective thickened, nearly square with a median ventral projection.

Aedeagus with shaft tapering to a pointed apex, a pair of long parallel processes some distance from apex; apodeme shorter than shaft, enlarged at apex with a median dorsal expansion.

Female genitalia.-- Ovipositor long, extending about its own width beyond pygofer. Pygofer long, somewhat concavely rounded at terminal end. Posterior margin of seventh sternim broadly rounded with a median emargination.

Host plants.— This species occurs almost entirely on lombardy poplar (Populus nigra var. italica Muenchh.), but has also been collected on cottonwood (Populus deltoidss Marsh.).

Tj e s .- The type of this species was not seen.

Distribution of material examined.— United States: California,

Illinois, Maryland, Massachusetts, New Jersey, New York, Ohio,

Pennsylvania, Virginia, Washington, and West Virginia.

Remarks.— A total of 75 specimens was examined. 35

Idiocerus crataegi Van Duzee

(Figs. 15, 59, 120, 162, and 207)

Idiocerus crataegi Van Duzee, 1890, p. 110} Osborn, 1905, p. 507j

Lawson, 1920, p. 6Uj DeLong, 1923, p. 63} Buys, 192U, p. 15;

Osborn, 1928, p. 212} Medler, 19U2, p. 11} DeLong, 19^8,

p. 120} Beime, 1956, p. 25.

A generally yellow species with prominent black spots on the vertex and pronotum, and black triangles on the scutellum.

Length: Male U.7 to 5.2 mm, female 5.2 to 5.7 mm. Width of head:

Male 1.7 to 1.9 mm, female 1.8 to 2.1 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus longer than wide; anteclypeus longer than wide, expanded at apex. Male antennae simple, without disc. Forewing flaring slightly, appendix large.

Color.— Vertex yellow with two very large black spots about their own width from eyes. Face mostly yellow with a small black spot beneath each ocellus. Pronotum yellow with two black triangular spots on the anterior margin. Scutellum yellowish brown with the triangles black. Forewing smoky with brown veins.

Male genitalia.— Plate short, very narrow, fringed with many long hairs. Pygofer short, rounded, appearing cylindrical. Style narrowing to a blunt apex. Connective expanded at both ends with a small ventral projection. Aedeagus with shaft short, slender, with a pair of long thin processes near apex, gonopore on ventral surface basal to processes; apodeme expanded at apex, with a dorsal expansion.

Female genitalia.— Ovipositor long, extending its own width beyond pygofer, Pygofer long and rounded. Posterior margin of

seventh sternum greatly produced with a median emargination.

Host plants.— This species occurs mainly on hawthome

(Crataegus sp.) but has also been collected on aspen (Populus sp.).

Type.— Lectotype male from Lancaster, New York, August, 1886,

E. P. V, (Iowa State College Collection); designated by Oman (I9k7)•

Distribution of material examined.— United States} Colorado,

Idaho, Illinois, Iowa, Kansas, New York, North Dakota, Ohio,

Pennsylvania, Texas, and Vfyoming. Canada: Ontario and Saskatchewan.

Remarks.— A total of 128 specimens was examined.

Idiocerus ramentosus (Uhler)

(Figs. Ik, 60, 119, 153, and 201)

By-bhoscopus ramentosus Uhler, 1877, p. k65.

Idiocerus ramentosus Gillette and Baker, 1895, p. 79j Lawson, 1920,

p. 65; Osborn, 1928, p. 212; Knowlton, 193k, p« 165;

DeLong, 19U8, p. 119.

Idiocerus mimicus Gillette and Baker, 1895, p. 76

Idiocerus brunneus Osborn and Ball, 1898, p. 72; Medler, 19k2, p. 11;

Beirne, 1956, p. 2k.

Idiocerus incriptus Van Duzee, 1917, p. 579. 3 7 Resembling crataegi in general form but larger with distinctly different genitalia. Length: Male U.8 to 5.8 mm, female 5.0 to

6.2 mm. Width of head: Male 1,8 to 2,1 inn, female 1.9 to 2.3 mm.

Vertex rounded, but more in the middle than near eyes, nearly same length in middle as near eyes. Postclypeus nearly same length as width; anteclypeus longer than wide, expanded at apex. Male antennae with a small disc at apex. Forewing flared, appendix large.

Color.— Vertex yellow brown with two black spots about one and one half their own width from eyes, usually a light yellow circle around each. Face yellowish brown. Male antennae with a black disc.

Pronotum and scutellum yellowish brown. Forewing smoky with brown veins interrupted with yellow.

Male genitalia.~- Plate very short, narrow, without setae.

Pygofer short, broadly rounded, appearing cylindrical. Style narrowing to a pointed apex. Connective expanded at both ends with a small ventral projection. Aedeagus with shaft narrowing to a pointed apex, gonopore apical, pair of long processes just basal to apex; apodeme expanded very little at apex with a dorsal expansion.

Female genitalia.— Ovipositor short, extending about its own width beyond pygofer. Pygofer short, appearing straight sided.

Posterior margin of seventh sternum greatly produced with a median emargination.

Host plants.— This species has been collected on Salix exigua

Nutt, and Salix interior Rowlee. 38

Type.-— A "cotype” female from Denver, Colorado, August 18,

1875, P. R. Uhler (United States National Museum Collection) is here designated lectotype.

Distribution of material examined,-- United States: California,

Colorado, Idaho, Illinois, Indiana, Iowa, Kansas, Missouri, Montana,

Nevada, New Mexico, New York, Ohio, South Dakota, Texas, Utah,

Wisconsin, and Vfroming. Canada: Manitoba and Saskatchewan,

Remarks,— A total of 232 specimens was examined,

t Idiocerus dolosus Ball

(Figs, 1, 2, 3, U, 11, 61, 116, 158, and 211)

Idiocerus dolosus Ball, 1902, p, 30li; Freytag, 1962, p. 2H5.

Generally yellowish brown with darker brown irregular markings.

Length: Male lu7 to 5,8 mm, female U.8 to 5,8 mm, Width of head:

Male 1.7 to 2.1 mm, female 1.8 to 2.2 ram.

Vertex slightly curved, nearly same length in middle as near

eyes. Postclypeus rounded, longer than wide; anteclypeus short,

constricted in middle, expanded at apex. Forewing flaring, giving

a robust appearance, venation obscure except for apical veins,

appendix large.

Color.— Vertex yellowish brown with two large black spots

about their own width from eyes, another pair of spots on hind margin

equally spaced between first two. Face yellowish brown patterned with

brownish fuscous spots; apical half of clypeus except for median 39

V-shaped area, black} antennae yellow, male with a black area slightly

distal to middle. Pronotum yellowish brown irregularly patterned with

brownish spots, except for a median area expanded in front. Forewing

yellowish brown; cells, except epical cells, with large fuscous areas;

apical veins dark brown; apical cells and appendix smoky brown,

Male genitalia.— Plate long, narrow, with a blunt apex.

Pygofer broadly rounded at distal end with a thickened ventral margin.

Style angled, somewhat twisted at apex, with a row of short spines.

Connective short and thickened. Aedeagus with shaft narrowing to a

spatulate apex, without processes, gonopore slitlike and extending

from middle to apex; apodeme wider but shorter than shaft, with a

small semicircular apex and a large median dorsal expansion.

; Female genitalia.— Ovipositor long, nearly pointed, extending

more than its width beyond pygofer. Pygofer nearly straight sided.

Posterior margin of seventh sternum rounded with a median

emiargination.

Host plants.— This species has been collected on Rhus

trilobata Hutt. and Quercus atahensis Rydberg. The type material

was seemingly collected by Dr. Ball on Rhus glabra L.

Type.— A "type" male from Dolores, Colorado, August 2, 1900

(United States National Museum Collection) is here designated the

lectotype; the genitalia are removed and in a vial attached to the

pin. Distribution of material examined,— United States: Arizona,

California, Colorado, New Mexico, and Utah,

Remarks,— A total of 350 specimens was examined,

Idiocerus ehisosus DeLong and Caldwell

(Figs, 13, 62, 117, 159, and 212)

Idiocerus chisosus DeLong and Caldwell, 1937, p. l6Uj Freytag, 1962,

p, 21*6.

Idiocerus caliginosus DeLong and Caldwell, 1937, p. 161*.

Resembles dolosus in general appearance, but smaller, darker and with distinctly different genitalia. Length* Male l*.l to

5,0 mm, female 3,9 to 5*2 mm. Width of head: Male 1.6 to 1.8 mm, female 1.5 to 1.8 mm.

Vertex slightly curved, nearly same length in middle as near eyes, Postclypeus longer than wide; anteclypeus nearly parallel sided. Forewing flaring, giving a robust appearance; venation obscure except for epical veins; appendix large.

Color.— Vertex yellow with two black spots about their own width from eyes. Face yellow patterned with brownish spots; anteclypeus dark brown except for a basal V-shaped area, yellowish brown; antennae yellow, male disc black. Pronotum yellowish brown irregularly patterned with brown, except for a median area which is expanded in front. Scutellum yellowish brown with black triangles and two pairs of dark spots near median line. Forewing with main veins yellowish white interrupted with black, apical veins dark

brown, main cells with fuscous areas, apical cells and appendix

smoky brown,

Male genitalia,— Plate long, narrow, nearly same width

throughout, Pygofer broadly rounded distally, slight median ventral

emargination, thickened ventral margin produced into a short terminal

spine. Style curved, narrowing to a fingerlike apex, with a row of

short spines. Connective thickened with a pointed ventral projection.

Aedeagus with shaft narrowing to a pointed apex, without processes,

gonopore apical to middle on ventral surface; apodeme expanded beyond

middle with a rounded apex and moderate dorsal expansion.

Female genitalia.— Ovipositor short, extending about its own

width beyond pygofer. Pygofer rounded. Posterior margin of seventh

sternum rounded with a median emargination.

Host plants.-- Unknown.

Type.— Holotype male from Davis Mts., Texas, July, 1936, J. N.

Knull (DeLong Collection),

Distribution of material examined.— United States t Texas,

Remarks,— A total of 228 specimens was examined. Idiocerus spinosus Freytag

(Figs. 12, 63, 118, 160, and 213)

Idiocerus splnosus Freytag, 1962, p. 2l|8.

Resembles dolosus in general appearance, but darker and with distinctly different genitalia. Length: Male It.7 to 5.1 mm, female U.6 to 5.2 mm. Width of head: Male 1.7 to 1.9 mm, female

1.8 to 2.0 mm.

Vertex slightly curved, nearly same length in middle as near eyes. Postclypeus rounded, raised, nearly same width as length;

anteclypeus parallel sides and slightly wider at apex. Male

antennae with a flattened disc just distal to middle. Forewing flaring, giving a robust appearance; venation obscure except for

apical veins; appendix large.

Color.— Vertex yellowish brown with two black spots about

their own width from eyes. Face yellowish brown patterned with brownish fuscous spots; anteclypeus dark brown except for a basal

U-shaped area, yellowish brown; antennae yellow, male disc black,

Pronotum yellowish brown irregularly patterned with brownish spots.

Scutellum yellowish brown with dark brown triangles and brown markings on each side of the median area. Forewing with main veins

yellowish white interrupted by dark brown areas, apical veins dark brown, main cells with fuscous areas, apical cells and appendix

smoky brown. Male genitalia,— Plate long, narrow, slightly pointed at apex,

Pygofer broadly rounded, with a median emargination on ventral margin, ventral margin thickened and developed into a spine distally from emargination. Style curved, narrowing to a nearly pointed apex, with a row of small spines near apex. Connective thickened, with a pointed ventral projection, Aedeagus with shaft angled, narrowing to a pointed apex, without processes, gonopore near middle on ventral surface; apodeme expanded beyond middle into pointed lateral projections, apical margin rounded, with a large broadly rounded dorsal expansion.

Female genitalia,— Ovipositor long, extending twice its own width beyond pygofer, Pygofer rounded, narrowed at distal end.

Posterior margin of seventh sternum rounded with a wide median emargination.

Host plants,-- Unknown,

Type,— Holotype male from Jacumba, California, July 26, 19l|0,

D, J. and J, N, Knull (Ohio State University Collection),

Distribution of material examined,— United States: Arizona and California. Mexico: Baja,

Remarks.— A total of 60 specimens was examined. Idiocerus snowi Gillette and Baker

(Pigs. 17, 6U, 121, 161, and 217)

A yellow green to cream yellow species with conspicuous black spots on the vertex. Length: Male 5.3 to 6.0 mm, female 5.6 to

6.5 mm. Width of head: Male 1.7 to 1.9 mm, female 1.8 to 2.1 mm.

Vertex slightly rounded, same length in middle as near eyes.

Postclypeus nearly same length as width; anteclypeus longer than wide, expanded at apex. Male antennae usually simple, without disc.

Forewing long, straight sided, with a large appendix.

Color.-- Vertex yellow with two black spots about twice their own width from eyes. Face yellow. Pronotum, scutellum, and forewings usually uniformly yellow, some however with black triangles on the scutellum, or a brown stripe on the sutural margin of clavus.

Male genitalia.— Plate long, narrow, same width throughout,

Pygofer narrowing to a slightly pointed apex. Style curved, narrowing to a pointed apex, with a row of short spines. Connective nearly

square with a pointed ventral projection. Aedeagus with shaft narrowing and curving to a pointed apex, a pair of processes near middle, gonopore just apical to processes on the ventral surface; t apodeme expanded greatly at apex, with a small dorsal expansion.

Female genitalia.— Ovipositor very long, extending twice its own width beyond pygofer. Pygofer long, unevenly rounded. Posterior margin of seventh sternum rounded but notched in middle. This species can be divided into two rather distinct subspecies on the basis of the color pattern. They can be separated by the following key:

1 Forewing with a dark brown stripe on the sutural margin of

clavus. Mostly east of the Rocky Mountains, - - - snowi raphus

1* Forewing without a dark brown stripe on the sutural margin

of clavus. Mostly from the Rocky Mountain west. - - snowi snowi

Idiocerus snowi snowi Gillette and Baker, new status

Idiocerus snowi Gillette and Baker, 1895, p. 79 j Khowlton, 1935,

p. Ill; Beirae (in part), 1956, p. 23

Idiocerus cauterus Ball and Parker, 19U6, p. 82,

Generally yellow to cream yellow with conspicuous black spots

on the vertex. Some specimens with dark markings on head, pronotum,

forewing, or pygofer. Male antennae simple, but rarely with a small

black disc near middle.

Type locality.— Not given in the original description, but

three ntypesn (2 males and 1 female) in the University of Kansas

Collection are labeled: "Colorado Springs, Colorado, 5915 ft,,

August, E. S, Tucker, type, snowi G, & B.w.

Type.— The male in the above mentioned series which is

pinned through the thorax (other male is pointed) is here

designated the lectotype. Host plants.— This subspecies occurs mostly on Salix exlgua

Nutt., but has also been collected on Salix acouleriana Barr.,

Ghrysothamnus speciosus Nutt., and Salsola pestifer A. Nels.

Distribution of material examined.— United States: Arizona,

California, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and

Washington. Canada: Manitoba.

Remarks.— This subspecies seems to be generally distributed throughout the West as far east as the eastern side of the Rocky

Mountains. A total of 553 specimens was examined,

Idiocerus snowi raphus subsp. n.

Idiocerus snowi. Lawson, 1920, p. 6U; DeLong, 1923, p. 66; Osborn,

1928, p. 210; Medler, 19U2, p. 11; DeLong, 19U8, p. 121;

Beime (in part), 1956, p. 23.

Generally yellow green with conspicuous black spots on the vertex and a dark brown stripe on the sutural margin of clavus.

Some male specimens with dark tipped pygofer. Male antennae simple.

Holotype male.— Cairo, Illinois, July 10, 1958, Boss and

Stannard, on Salix interior. Allotype female.— Same data as

holotype. Paratypes.— Four males and five females, same data as

holotype, Holotype, allotype, and seven of the paratypes in the

Illinois Natural History Survey Collection. One male and one

female para type in the DeLong Collection. Host plants,— This subspecies occurs mostly on Salix interior

Rovlee, but has also been collected on Salix nigra Marsh., Salix

cordata Michx., Salix exigua Nutt., and Populus deltoides Marsh.

Distribution of material examined.— United States: Illinois

Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska,

North Dakota, Ohio, South Dakota, Wisconsin, and looming. Also

from the District of Columbia.

Remarks.— This subspecies is generally distributed East of

the Rocky Mountains. A total of 202 specimens was examined.

Idiocerus moniliferae Osborn and Ball

(Figs. 18, 68, 111, 163, and 208)

*

Idiocerus moniliferae Osborn and Ball, 1898, p. 71 j Dawson, 1920,

p. 65; Medler, 19U2, p. 10; DeLong, 19U8, p. 122.

Idiocerus distinguendus. Beime (in part) (not KirscUbaum, 1866),

1956, p. 23.

A medium sized species with a color pattern resembling

altematus. Length: Male 3.0 to 3.6 mm, female U.7 to 5.7 mm.

Width of head; Male 1.8 to 2.1 mm, female 1.8 to 2.1 mm.

Vertex curved, longer near eyes than near middle. Postclypeus

angled, wider than long; anteclypeus longer than wide, slightly

expanded at apex. Male antennae simple, without disc. Forewing

flaring, giving a robust appearance, venation normal, appendix

large. Color.-- Vertex yellowish brown with two black spots nearly twice their own width from eyes. Face yellowish brown patterned with brown, large brown patch between ocellus, black spot on vertex, and eye. Pronotura yellowish brown patterned with brown spots except for median line. Scutellum dark yellow brown with black triangles and brown markings near median line. Forewing smoky yellow brown with veins yellow interrupted with brown,

Male genitalia.— Plate long, thickened nearly to apex,

Pygofer long, nearly same width to apical third which narrows to a somewhat pointed apex. Styles broad, expanded at apex, with a row of short spines on lateral margin. Connective long, slender, shape of an inverted-I'T" with a ventral pointed projection. Aedeagus with a tubular shaft which is constricted at apical end, gonopore near apex* apodeme slightly wider than shaft, apex forming a bell-shaped structure with a dorsal projection.

Female genitalia.— Ovipositor short, extending about its own width beyond pygofer. Pygofer rounded. Posterior margin of seventh sternum strongly rounded with a shallow median emargination.

Host plants.— Specimens have been collected from cottonwood,

Populus deltoides Marsh.

Type.— Lee to type female from Exp. St a., Ames, Iowa, June 19,

1897 (Iowa State College Collection)j designated by Oman (19U7). h9

Distribution of material examined,— United States: Arizona,

California, Colorado, Connecticut, Illinois, Indiana, Iowa, Kansas,

Mississippi, Nebraska, New Mexico, Ohio, Utah, West Virginia, and looming.

Remarks.-- A total of 93 specimens was examined,

Idiocerus cognatus Fieber

(Figs. 19, 58, 122, 16U, and 20U)

Idiocerus cognatus Fieber, 1868, p. U55; Melichar, 1896, p. I6lj

DeLong, 1923, p. 62j DeLong, 19U8, p. U.6.

Idiocerus distinguendus. Ribaut (in part) (not Kirshbaum, 1868),

1952, p. 379j Beirne (in part), 1956, p. 25.

A small pale, faintly banded species, introduced from Europe.

Length: Male 1*.5 to U.8 mm, female lu9 to 5.3 mm. Width of head:

Male 1.6 to 1.7 mm, female 1.7 to 1.8 mm.

Vertex slightly curved, longer near eyes than in middle.

Postclypeus angled, longer than wide; anteclypeus longer than wide, expanded at apex. Male antennae simple, without disc. Forewing with venation nearly obscure, appendix large.

Color.— Vertex yellow and usually with two black spots about their own width from eyes. Face yellow. Pronotum yellow mottled 1 with brown. Forewing yellow banded with brown across middle, apical veins brown. Male genitalia,— Plate short, thickened nearly to apex,

Pygofer nearly same length as plates, pointed terminally. Style nearly same width throughout, apex narrowed and pointed. Connective stout, somewhat triangular with a pointed ventral projection.

Aedeagus with shaft narrowing to a flat, pointed apex, gonopore just subapical on ventral surface, barblike process on each side basal to phallotreme; apodeme constricted in middle then expanded apically with a rounded dorsal expansion.

Female genitalia.-- Ovipositor short, extending about its own width beyond pygofer. Pygofer rounded with a slight terminal indentation. Posterior margin of seventh sternum slightly arcuate.

Host plants.— Specimens have been collected on white poplar

(Pppulus alba L.). '

T226.— The type of this species was not seen.

Distribution of material examined.— United States: New

Jersey, New York, Ohio, and Pennsylvania.

Remarks.— Upon examination of European specimens of both cognatus and distlnguendes in the British Museum, I find that these should be considered separate species. Besides genitalic differences these two can be easily separated by the shape of the tip of the gena; in cognatus they are rounded, and in distlnguendes they are pointed.

A total of 58 specimens was examined. 51

Idiocerus rufns Gillette and Baker

(Figs. 20, 69, 123, 165, and 203)

Idiocerus rufus Gillette and Baker, 1895, p. 80.

Idiocerus rufus var. cingulatus Ball, 1902, p. 312.

Idiocerus nogalinus Ball and Parker, 19U6, p. 8 0 . (new synonymy)

Resembling cognatus in structural form, but differs in the color pattern and genitalia. Length: Male U.9 to 5.2 mm, female 5.2 to

5.6 mm. Width of head: Male 1.7 to 1.8 mm, female 1.8 to 1.9 mm.

Vertex slightly curved, nearly same length in middle as near

eyes. Postclypeus longer than wide; anteclypeus longer than wide,

expanded at apex. Male antennae simple, without disc. Forewing

flaring slightly, venation mostly obscure, appendix very large.

Color.— Vertex and face yellow, antennae brown. Pronotum

and scutellum brown with irregular yellow spots. Forewing brown,

some specimens with a yellow spot near middle, male usually with

a yellow band across basal part of apical region.

Male genitalia.— Plate long, thickened almost to apex.

Pygofer long narrow, pointed terminally. Style nearly same width

throughout, but narrowing at apical end to a pointed apex.

Connective short, stocky, with a ventral pointed projection.

Aedeagus with shaft narrowing slightly to a flattened rounded apex,

gonopore just subapical on ventral surface, a short lateral process

on each side basal to gonopore; apodeme expanding apically forming

a triangular apex, with a large median dorsal expansion. 52

Female genitalia.— Ovipositor short, blunt, extending about its own width beyond pygofer, Pygofer rounded and thick. Posterior margin of seventh sternum slightly rounded with a narrow median emargination.

Host plants.— Specimens have been collected on Populus balsamifera L,, Populus angustlfolia James, and Solidago.

Type.— A female "type” from Hist Canon near Fort Collins,

Colorado, September 27, I89U, C. P. Gillette, on Solidago (Colorado

State University Collection) is here designated the lectotype. The label on this specimen states only the following: "Colo., #1771, type".

Distribution of material examined.— United States: Arizona,

California, Colorado, Utah, and Vfyoming.

Remarks.— A total of 270 specimens was examined.

Idiocerus clnctus DeLong and Caldwell

(Figs. 21, 66, 121*, and 166)

Idiocerus cinctus DeLong and Caldwell, 1937a, p. 163*

Idiocerus bovinus Ball and Parker, 191*6, p. 163.

Idiocerus distinguendus. Beime (not Klrshbaum) (in part), 1956, p. 25.

Resembling rufus in general appearance, but larger, darker, and

with distinctly different male genitalia. Length: Male 5.6 to 5.8

mm, female 5.7 to 5.5 mm. Width of head: Male 1.8 to 1.9 mm, female

2.0 to 2.1 mm. 53

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus nearly same width as length; anteclypeus longer than wide, greatly expanded at apex. Hale antennae simple, without disc. Forewlng flaring, venation nearly obscure, appendix large.

Color.— Vertex and face yellow brown; antennae yellow.

Pronotum brown with irregular yellow spots and a yellow margin.

Scutellum brown mottled with yellow, sometimes with dark brown triangles. Forewing brown, with two yellow white bands, one across clavus, other across apical part of anteapical cells.

Male genitalia.— Plate long, thickened nearly to apex.

Pygofer long, narrow, with a pointed apex. Style sharply pointed at apex, with a constriction near middle. Connective stocky, with a thin median ventral projection. Aedeagus with shaft narrowing to a flattened apex, gonopore subapical on ventral surface, a lateral process on each side of shaft just basal to gonopore; apodeme large, with a very large median dorsal expansion.

Female genitalia.— Ovipositor short, blunt, extending about its own width beyond pygofer. Pygofer short and rounded. Posterior margin of seventh sternum rounded with a median emargination.

Host plants.— This species has been collected on cottonwood

(Populus sp.) and alfalfa.

Type.— Holotype male from Idaho City, Idaho, July 13, 1930,

(Delong), (DeLong Collection).

Distribution of material examined.— United States: Arizona,

Idaho, Nevada, Oregon, and Washington. Canada: British Columbia.

\ 5U

Remarks,— This species is very closely related to rufus, but the overall size and the size and shape of the male genitalia •will separate them. The female genitalia is very similar to rufus. A total of 70 specimens was examined,

Idiocerus Btigmaticalis Lewis

(Figs. 56, 72, 115, 157, and 2lU)

Idiocerus stigmaticalis Lewis, 183U, p. U8.

Bythoscopus adustus Herrich-Schaeffer, 1837, p. 9.

A rather large, well marked leafhopper, with the leading edge of the forewing with a heavy asperate area. Length: Male 6.1 to

6.6 mm, female 6.2 to 7*2 ram. Width of head: Male 2,k to 2.5 mm, female 2.5 to 2.6 mm.

Vertex evenly rounded, longer near eyes than in middle.

Postclypeus same width as length; anteclypeus longer than wide, only slightly expanded at apex. Male antennae with small round apical disc, Gena of male clothed with many fine setae. Forewing flaring, with costal margin thickened and asperate, outer anteapical cell always open.

Color.— Vertex and face unicolorus yellow brown, sometimes with a pair of small spots on vertex about twice their own width from eyes. Pronoturo yellow brown, mottled with brown, with dark brown spots along anterior margin. Scutellum yellow brown with dark brown triangles. Forewing yellow brown with brown veins; male costal margin black and yellow with asperate area pink, orange spot near apex covering from costal margin to- apex of outer anteapical cell.

Male genitalia.— Plate long, thin, nearly same width throughout. Pygofer thick, with a rounded apex. Style arched to a nearly pointed apex, with an enlarged spine near apex. Connective

shaped like an inverted "TM, with a pointed ventral projection.

Aedeagus with shaft narrowing to a flattened apex, gonopore on ventral

surface at basal edge of flattened area, a short process on each side

of shaft just apical to gonopore; apodeme enlarged, thick, with a median dorsal expansion.

Female genitalia.— Ovipositor short but thick, extending

its own width beyond pygofer. Pygofer short and broadly rounded.

Posterior margin of seventh sternum greatly produced in middle.

Host plants.— This species occurs mainly on willows (Salix

sp.) but sometimes on poplars (Populus sp.) in Europe (Ribaut,

1952). Its host in this region is unknown.

2ZE2.,““ The type of this species was not seen.

Distribution of material examined.— Only one series of

specimens, U males, 12 females, and 1 nymph, from an Arboretum

near Boston, Massachusetts collected in July (probably in the

1800*s) has been examined.

Remarks.— It is not known wheather this species has become

established in the Nearctic region, but is included here in the

event it is again collected. Idiocerus lachrymal!s Fitch

(Figs. 30, 82, 113, 173, and 22U)

Idiocerus lachrymalis Fitch, 1851, p. 58j Gillette and Baker, 1895,

p. 76} Osborn, 1905, p. 507} DeLong, 1923, p. 63; Buys,

1921*, p. 15; Osborn, 1928, p. 211; Khowlton, 193U, p. 165;

Knowlton, 1935, p. H I ; Medler, 19l*2, p. 10; Beirne, 1956,

P* 25.

Idiocerus rondulus Ball and Parker, 19U6, p. 73. (new synonymy)

Idiocerus hebetus DeLong and Hershberger, 19U7, p. 1*8; DeLong, 19U8, i p. 119. (new synonymy)

A rather large, long, yellow brown species, with dark veins on forewings. Length: Hale 6.0 to 6.5 mm, female 6.2 to 7.1 mm*

Width of head: Hale 2.1 to 2,2 mm, female 2.2 to 2.1* mm.

Vertex wide, little longer near eyes than in middle. Fostclypeus longer than wide; anteclypeus longer than wide, little expanded at apex. Hale antennae, with large disc, tapered at both ends. Forewing flaring, with a large appendix.

Color.— Vertex of male unicolorus yellow, with a pair of faint brown spots about twice their own width from eyes. Vertex of female yellow, with a pair of round black spots about twice their own width from eyes, an elongate spot against each eye, and usually these two pairs of spots connected by a transverse black band. Face of male unicolorus yellow, antennal disc black. Face of female unicoloruir yellow. Pronotum yellow mottled with yellow brown, with dark brown spots along anterior margin. Scutellum yellow with dark brown triangles and spot on median line. Forewing yellow brown with dark brown veins, second claval vein spotted with yellow at apex.

Male genitalia.-— Plate long, thin, nearly same width to apex,

Pygofer short, very wide, with a rounded apex. Style nearly same width to a pointed apex, with several short combined apical spines.

Connective nearly- rectangular in shape, with a ventral pointed projection. Aedeagus with shaft tubular to apex, gonopore at apex, a short spine-like process on each side of shaft at their own length from apex; apodeme enlarged at apex, with a slight dorsal expansion.

Female genitalia.— Ovipositor long, extending nearly twice its own width beyond pygofer. Pygofer long and almost evenly rounded. Posterior margin of seventh sternum produced in middle.

Host plants.— This species has been collected on Populus tremuloides Michx. and Populus angustifolia James.

Type.— The type of this species was not seen.

Distribution of material examined.— United States: Arizona,

California, Colorado, Idaho, Maine, Michigan, Minnesota, Montana,

New Hampshire, New Mexico, New York, North Dakota* Pennsylvania,

South Dakota, Utah, Vermont, Washington, Wisconsin, and Wyoming.

Canada: Alberta, British Columbia, Manitoba, and Ontario.

Remarks.— A total of 3h7 specimens was examined. 58

Idiocerus formosua Ball

(Figs. 29, 81, 112, 172, and 223)

Idiocerus formosus Ball, 1902, p. 305; Medler, 19U2, p. 10.

Resembling lachrymalis in general shape, but smaller and more heavily marked. Length: Male 5*2 to 5.9 mm, female 5.7 to 6.3 mm.

Width of head: Male 1.8 to 2.0 mm, female 2.0 to 2.3 mm.

Vertex wide, evenly but only slightly rounded. Postclypeus longer than wide; anteclypeus longer than wide, little expanded at apex. Male antennae with a large apical disc, which is about twice as long as wide. Forewing flaring, with a large appendix.

Color.-- Vertex of male yellow, with a pair of round black spots about twice their own width from eyes, an elongate spot against each eye, and usually these two pairs of spots connected by a transverse black band. Vertex of female similar, but markings lighter. Face of male unicolorus yellow; antennal disc black. Face of female unicolorus yellow. , Pronotum and scutellum yellow mottled with brown. Forewing of male brown, with dark brown veins, yellow spot across apex of second claval vein, and an irregular yellow band across anteapical cells. Forewing of female yellow brown, with brown veins, but sometimes marked as in the male.

Male genitalia.— Plate long, thin, little wider near apex than at base. Pygofer stocky, with a rounded apex. Style nearly same width to a pointed apex, with long combined apical spines.

Connective short, shaped like an inverted "T", with a ventral pointed projection. Aedeagus with shaft tubular to apex, gonopore at apex, a spine-like process on each side of Bhaft at their own length from apex* apodeme enlarged at apex, with a slight dorsal expansion.

Female genitalia.— Ovipositor long, extending twice its own width beyond pygofer. Pygofer long, evenly rounded then narrowed near apex. Posterior margin of seventh sternum widely produced in middle.

Host plants.— This species has been collected on Populus tremuloides Michx. and Populus tremuloides var. aurea (Tidestrom)

Daniels.

Type.— A •’type” male specimen from Happy Hollow, Colorado,

July 21, I898 (United States National Museum Collection) is here designated the lectotype*

Distribution of material examined.— United States: Arizona,

California, Colorado, Idaho, Massachusetts, Michigan, Minnesota,

Montana, New Mexico, New York, South Dakota, Utah, Vermont,

Washington, Wisconsin, and Wyoming. Canada: British Columbia*

Manatoba, and Ontario.

Remarks.— A total of E>90 specimens was examined.

Idiocerus maximus sp. n.

(Figs. 31, 83, 11U, 17U, and 22$)

Resembling lachrymalis in general appearance, but larger,

.darker, and with distinctly different genitalia* Length: Male 7.1 to 7.5 mm, female 7.5 to 8.0 mm. Width of head: Male 2.5 to

2.7 mm, female 2.7 to 2.8 mm.

Vertex very wide, nearly same length in middle as near eyes.

Postclypeus longer than wide; anteclypeus longer than wide, expanded at apex, Male antennae with a large nearly circular disc at apex.

Forewing long, flaring, with a large appendix.

Color.— Vertex of male yellow, usually with a pair of brown spots about twice their own width from eyes. Vertex of female mostly dark brown, with posterior margin yellow and two black spots

about twice their own width from eyes. Face of male unicolorus yellow;' antennal disc black. Face of female yellow, with brown

spots around ocelli, near base of antennae, and under eyes. Pronotum yellow, brown, greatly spotted with dark brown along anterior margin.

Scutellum yellow brown, with dark brown triangles and spot down median. Forewing of male yellow brown, basal part of clavus brown,, band across wing at apex of clavus brown, appendix and apical cells brown, with dark brown veins, yellow spot at apex of second claval vein and another at apex of clavus. Forewing of female same

general pattern as male but lighter in color.

Male genitalia.— Plate very long, thin, nearly same width

to apex. Pygofer long, with a rounded apex. Style nearly same

width to a pointed apex,, with several combined spines at apex.

Connective nearly rectangular, with a ventral pointed projection.

Aedeagus with shaft tubular to apex, gonopore at apex, a short

spine-like process on each side of shaft at their own length from

apexj apoderae enlarged at apex, with a dorsal expansion. 61

Female genitalia,— Ovipositor very long, extending over three times its own width beyond pygofer, Fygofer long, evenly rounded then narrowed near apex. Posterior margin of seventh sternum produced in middle.

Host plants,— This species has been collected on cottonwood

(Populus sp,) and golden aspen (Populus tremuloides var. aurea

(Tidestrom) Daniels),

Holotype male,— San Francisco Mts., Arizona, August 12, 1929,

E. D, Ball, Allotype female,— Same data as holotype, Paratypes,—

7 males, 3 females, same data as holotype. All type material in the

United States National Museum Collection,

Distribution of other material examined,— United States:

Colorado.- Estes Park, 1 male, August 21, 1920, H. C. Severin,

New Mexico,- Beulah, 1 male, July 27, Cockerell, Utah,- Richfield,

1 female, July 15, 1929, light trap; 1 male, July 8, 1930, E, W,

Davis; U males, 3 females, July 1$, 1930, light trap; 2 males,

6 females, July 20, 1930, Kimberly Mts., Populus aurea: 1* males, h females, July 23, 1933,, E. W. Davis. Ft. Duchesne, 1 male,

August 20, 1932, Logan, 1 female, July 20, 1929, G. F, KnowLton.

Logan Canyon, 1 female, August 19, 1911;. Ephreim, 1 female, July

20, 19lU, E. D, Ball. Washington.- Cliffdell, 1 female, July 7,

1935, Oman. Puyallup, 1 female, July 6, 1935, Oman. Canada:

British Columbia.- Duncan, 2 females, September 17, 1925,

W. Downes, Cottonwood. 62

Idiocerus pallldus Pitch

(Figs. 23, 79, 105, 167, and 218)

Idiocerus pallidus Fitch, 1851, p, 59j Gillette and Baker, 1895,

p. 76j Osborn, 1905, p. 505j DeLong, 1916, p. 21;

Lawson, 1920, p. 68; DeLong, 1923, p. 65j Buys, 192U,

p. 12; Osborn, 1928, p. 209; Knovlton, 1935, p. 165;

Medler, 19^2, p. 8; DeLong, 19U8, p. 117.

Bythoscopus obsoletua Walker, 1851, p* 873*

Idiocerus borealis DeLong and Caldwell, 1937a, p. 161. (new synonymy)

Idiocerus telus DeLong and Hershberger, 19U7, p. k5» (new synonymy)

Idiocerus popnli. Beirne (not Linne) (in part), 1956, p. 23.

A medium sized species with a uniform yellow to green color.

Length: Male 6.0 to 6.U mm, female 6.6 to 7.0 mm. Width of head:

Male 2.0 to 2.1 mm, female 2.1 to 2.2 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus longer than wide; anteclypeus longer than wide, with apex expanded. Male antennae with an oval disc at apex.

Forewing flaring, venation obscure, with a large appendix.

Color.— Vertex and face unicolorus yellow or yellow orange; male antennal disc black. Pronotum and scutellum yellow to yellow green. Forewing yellow to yellow green.

Male genitalia.-- Plate long, thin, nearly same width to apex.

Pygofer broad with a pointed apex. Style arched and narrowed to a pointed apex, with several combined spines near apex. Connective large, nearly rectangular, with a ventral pointed projection,

Aedeagus with shaft tubular to apex, gonopore at apex, a short process on each side of shaft about their own length from apex; apodeme enlarged at apex, with a dorsal expansion.

Female genitalia,— Ovipositor long, extending one and a half times its own width beyond pygofer, Pygofer long, rounded, but narrowed near apex. Posterior margin of seventh sternum rounded with a produced median.

Host plants,— This species has been collected on cottonwood

(Populus sp,) and willows (Salix araygdaloides Anders,. Salix nigra

Harsh., Salix exigua Nutt,, and Salix ? monticola Bebb.).

Type.— The type of this species was not seen.

Distribution of material examined.— United States: Arizona,

California, Colorado, District of Columbia, Idaho, Illinois, Iowa,

Kansas, Massachusetts, Maryland, Minnesota, Michigan, Montana,

Nebraska, Nevada, New Hampshire, New Mexico, New York, Ohio, Oregon,

Pennsylvania, South Dakota, Tennessee, Utah, Washington, Wisconsin,

and Wyoming. Canada: British Columbia, Manitoba, Nova Scotia,

and Ontario.

Remarks.— A total of 10f>l specimens was examined. 6k

Idlocerns duzeei Provancher

(Figs, 5, 2li, 80, 106, 168, and 21?)

Idiocerus duzeei Provancher, 188?, p, 290; Lawson, 1920, p. 69;

DeLong, 1923, p. 63; Osborn, 1928, p, 210; Knowlton,

1935, p. 110; Medler, 19U2, p. 9; DeLong, 19U8, p, 118.

Idiocerus populi, B e i m e (not Linne) (in part), 1956, p. 23

Resembling pallidus in general appearance, but larger, darker, and with distinctly different genitalia. Length: Male 5.9 to 6.5 mm, female 6.9 to 7*5 mm. Width of head: 2.1 to 2.2 mm, female

2.3 to 2.5 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus longer than wide; anteclypeus longer than wide, with apex expanded. Male antennae with a small oval disc at apex.

Forewing flaring, venation nearly obscure, with a large appendix.

Color.-- Vertex and face yellow orange, a faint orange band across face above ocelli; male antennal disc black. Fronotum yellow orange. Scutellum yellow orange with orange triangles.

Forewing of male yellow orange, with basal part bright orange, veins orange, and apical cells and appendix smoky brown. Forewing of female same pattern as male but much lighter.

Male genitalia.— Plate long, thin, wider near apex. Pygofer long, rounded at apex. Style arched to a pointed apex, with several large combined spines near apex. Connective large, nearly rectangular, with a ventral pointed projection. Aedeagus with shaft tubular to apex, gonopore at apex, a short process on each side of shaft about their own length from apex; apodeme enlarged at apex, with a dorsal expansion.

Female genitalia.— Ovipositor long, extending a little more than its own width beyond pygofer. Pygofer long, broadly rounded, but narrowed near apex. Posterior margin of seventh sternum rounded, with a produced median.

Host plants.— This species has been collected on Populus deltoides Marsh., Populu3 Fremontii S. Wats., and Populus Sargentii

Dode.

Type.— The type of this species was not seen.

Distribution of material examined.— United States: Arizona,

California, Colorado, Illinois, Iowa, Kansas, Louisiana, Minnesota,

Missouri, North Dakota, Ohio, Oregon, South Dakota, Tennessee, Utah,

Wisconsin, and looming. Canada: British Columbia.

Remarks.— A total of 155 specimens was examined.

Idiocerus perplexus Gillette and Baker

(Figs. 27, Ik, 129, and 171)

Idiocerus perplexus Gillette and Baker, 1895, p. 78.

Idiocerus levis DeLong and Caldwell, 1937a, p. 161. (new synonymy)

Idiocerus populi. Beirne (not Linne) ( in part), 1956, p. 23.

Resembling pallidus in general appearance, but with distinctly

different male genitalia. Length: Male 5.3 to 5.9 mm, female 5.5 66 to 6.U mm. Width of head: Male 1.8 to 1.9 mm, female 1,9 to 2,1 mm.

Vertex evenly rounded, nearly same length in middle as near eyes, Postclypeus much longer than wide; anteclypeus longer than wide, with an expanded apex. Male antennae with a thin oval disc at apex, Forewing flaring, venation nearly obscure, with a large appendix.

Color,— Vertex and face yellow, male antennal disc black,

Pronotum and scutellum yellow, Forewing yellow, with veins deep yellow*

Male genitalia*— Plate long, thin, wider near apex, Pygofer wide, rounded, with a nearly pointed apex. Style nearly same width

to a sharply pointed apex, with several large spines near apex.

Connective shaped like an inverted MTtt, with a pointed ventral projection, Aedeagus with shaft tubular to apex, gonopore at apex,

a long process on each side of shaft about their own length from

apexj apodeme greatly enlarged at apex, with a large dorsal expansion.

Female genitalia.— The female genitalia of this species is

seemingly the, same as pallidus*

Host plants,— This species has been collected on cottonwood

(Populus sp,).

Type.— A "type” male specimen from Colorado Springs, Colorado,

August, E. S. Tucker (Colorado State University Collection), is here

designated the lectotype. Distribution of material examined,— United Statesj Colorado

Maine,

Remarks,— Very few specimens have been seen of this species but the longer processes on the aedeagus will identify it, A total of 9 specimens was examined,

Idiocerus suturalls Pitch

(Figs. 26, 76, 128, 170, and 226)

Idiocerus suturalls Fitch, 1851, p, 59; Fillette and Baker, 1895,

p, 86; Osborn, 1905, p, 506; Lawson, 1920, p. 68; DeLong,

1923, p. 66; Buys, 192U, p. 12; Osborn, 1928, p, 209;

Know!ton, 193U, p, 165; Medler, 19U2, p. 8; DeLong, 19U8,

P. 116,

Idiocerus suturalls var. continues Ball, 1902, p, 312,

Idiocerus suturalls var, lunaris Ball, 1902, p. 311; DeLong, 1923,

p. 66; Buys, 192U, p. 13; Osborn, 1928, p, 210; Medler,

19h2, p. 8.

Idiocerus stellaris DeLong and Caldwell, 1937a, p, 162. (new

synonymy)

Idiocerus populi. Beirne (not Linne) (in part), 1956, p. 23.

A pale yellow species with a wide brown band along suture of forewings, this sometimes interrupted, and often continuing forward as far as the pronotum. Lengthi Male 5.1 to 5.5 mm, female 5.7 to 6.3 mm. Width of head: Male 1.7 to 1.8 mm, female 1,8 to 2.1 mm. 68

Vertex evenly rounded, nearly same length In middle as near eyes. Postclypeus longer than wide; anteclypeus longer than wide, with an expanded apex. Male antennae with a small oval or long

oval disc at apex. Forewing flaring, venation nearly obscure, with

a large appendix.

Color.— Vertex and face yellow, male antenna! disc black.

Pronotum yellow to nearly all dark brown with a yellow anterior margin. Scutellum brown with dark brown triangles to all dark brown.

Forewing yellow with clavus mostly dark brown, appendix smoky brown,.

sometimes dark brown on clavus is interrupted with yellow.

Male genitalia.— Plate long, thin, wider at apex. Pygofer

wide, with a bluntly pointed apex. Style narrowing very little to

a pointed apex, with several large combined spines at apex.

Connective robust, shaped like an inverted "T", with a ventral

pointed projection. Aedeagus with shaft tubular to apex, gonopore

at apex, a long thin process on each side of shaft about their own

length from apex; apodeme enlarged at apex, with a large dorsal

expansion.

Female genitalia.— Ovipositor short, extending its own width

beyond pygofer. Pygofer short, broadly rounded. Posterior margin

of seventh sternum angled to a produced median.

Host plants.— This species has been collected on aspen

(Populus tremuloides Michx.) and golden aspen (Populus tremuloides

var. aurea (Tidestrpm) Daniels).

The type of this species was not examined. Distribution of material examined,-- United States: Arizona,

Colorado, Idaho, Illinois, Maine, Michigan, Montana, New Mexico,

New York, North Dakota, Ohio, Pennsylvania, South Dakota, Utah,

Vermont, Washington, Wisconsin, and Vfyoming. Canada: British

Columbia and Manitoba,

Remarks,— There is a considerable amount of variation in the color pattern of this species, A total of 676 specimens was examined,

Idiocerus vagus Ball

(Figs. 25, 78, 107, 169, and 220)

Idiocerus auturalis var, vagus Ball, 1902, p. 312,

Idiocerus populi, B eime (not Linne) (in part), 1956, p. 23,

Resembling suturalis in general appearance, but lighter in color and with distinctly different genitalia. Length: Male

5.2 to 5.8 mm, female 5.5 to. 6.1 ram. WLdth of head: Male 1.7 to 2.0 mm, female 1.9 to 2.1 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus longer than wide; anteaclypeus longer than wide, expanded at apex. Male antennae with a long oval disc at apex.

Forewing flaring, venation nearly obscure, with a large appendix.

Color.— Vertex and face of male yellow, antennal disc black.

Vertex and face of female light yellow. Pronotum yellow. Scutellum yellow with brown triangles. Forewing yellow with clavus and

appendix smoky brown. Female often uniformly yellow. 70

Male genitalia,— Plate long, thin, little wider near apex,

Pygofer wide, with a bluntly pointed apex. Style narrowing slightly

to a thick but pointed apex, with several combined spines at apex.

Connective nearly rectangular, with a ventral pointed projection,

Aedeagus with shaft tubular to apex, gonopore at apex, a long curved process on each side of shaft about their own length from apexj

apodeme enlarged at apex, with a small dorsal expansion.

Female genitalia,— Ovipositor long, extending almost twice ,

its own width beyond pygofer, Pygofer long, rounded, but narrowed

near apex. Posterior margin of seventh sternum with a large

produced median.

Host plants.— This species has been collected on willows

(Salix irrorata Anders., Salix lucida Muhl., Salix cor data Muhl,,

Salix planifolia Pursh., Salix fragilis L., and Salix padophylla

Rydb., Salix lutea Nutt., Salix bebbiana Sarg., Salix ligulifolia

Ball, and Salix 7 monticola Bebb,),

2ZE2..— The "types" of this species were not examined but

are from North Park, Colorado,

Distribution of material examined.— United States* Colorado

and Vfyoming.

Remarks.— The male of this species resembles suturalis but

is usually much lighter in color. The female resembles pallidus

but sometimes has the color pattern of the male. The host plants

for the three species seem to be quite different. A total of 580

specimens was examined. 71

Idiocerus amoenus Van Duzee

(Figs. 32, 92, 132, 185, and 232)

Idiocerus amoegus Van Duzee, l89h, p. 89. Misspelled.

Idiocerus amoenus Gillette and Baker, 1895, p. 7k; Van Duzee, 1917,

P. 575.

Idiocerus pictus Van Duzee, 1917, p. 289.

Idiocerus wiyotus Bliven, 1951*, p. Ill;, (new synonymy)

A small yellow orange species with pale markings. Length:

Male U.7 to 5.0 mm, female 5*0 to 5.2 mm. Width of head: Male

1.6 to 1.8 mm, female 1.7 to 1.8 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus nearly same width as length} anteclypeus longer

than wide, not expanded at apex. Male antennae with a large oval

disc at apex. Forewing long, flaring slightly, venation nearly

obscure, with a large appendix.

Color.— Vertex and face of male uniformly yellow with a faint brown band through each gena, antennal disc black. Vertex and face

of female uniformly yellow orange with gena yellow. Fronotum yellow

with orange patches. Scutellum mostly orange with yellow spots near

middle. Forewing yellow orange with a smoky orange area at base of

clavus and a smaller one at apex of clavus.

Male genitalia.— Plate short, narrow, same width throughout,

with a blunt apex. Pygofer short, narrow, with a bluntly pointed

apex. Style short, curved to a blunt apex, several short combined 72 spines at apex. Connective shaped like an inverted MTn, with a median ventral pointed projection. Aedeagus with shaft curving to a long, narrow, flattened apex, gonopore at base of flattened area, with a short process on each side just basal to gonopore; apodeme expanded at apex, with a small median dorsal expansion.

Female genitalia.— Ovipositor of median length, extending its own width beyond pygofer. Pygofer broadly rounded. Posterior margin of seventh sternum roundedly produced with a median emarglnation.

Host plants.— This species has been collected on Populus fremontii S. Wats., Populus deltoides Marsh., Populus angustifolia

James, Salix nigra Marsh., Salix lutea Nutt., Salix aaygdaloides

Anderss., Salix lasiandra Benth., Sequoia sempervirens (D. Don)

Endl., and Juniperus sp.

Type.-- Lectotype female from California (Los Angeles),

CoquHlett, 220 (Iowa State College Collection); designated by

Oman (19^7)•

Distribution of material examined.— United States t Arizona,

California, Colorado, New Mexico, Oregon, and Washington.

Remarks.— A total of U60 specimens was examined. 73

Idiocerus depictus Ball

(Figs. 33, 93, 133, 186, and 233)

Idiocerus amoenus var. depictus Ball, 1902, p. 313«

Resembling amoenus in general appearance, but with a different color pattern and with distinctly different genitalia. Length:

Male U.U to 5.0 mm, female U.7 to 5.U mm. Width of head: Male

1.6 to 1.7 mm, female 1.7 to 1.8 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus same width as length* anteclypeus longer than wide, expanded at apex. Male antennae with a small, long disc at apex.

Forewing long, flaring, venation except for apical veins obscure, with a large appendix.

Color.— Vertex and face uniformly yellow, male disc black.

Pronotum yellow, with large circular spots (orange in female and brown in male) covering most of the posterior lateral area, and with a small yellow spot in the middle of each. Scutellum uniformly orange in female; orange brown with brown triangles in male.

Forewing yellow with basal area of clavus brown, saddle across

apex of clavus brown, and appendix smoky brown.

Male genitalia.— Plate curved, narrow, with a blunt apex.

Pygofer short, narrow, with a nearly pointed apex. Style curved, nearly same width to apex, several short combined spines at apex.

Connective shaped like an inverted "T", with a median ventral projection. Aedeagus with shaft curved to a flattened apex, gonopore at base of flattened area on ventral surface, short process on each side opposite gonopore; apodeme expanded at apex with a median dorsal expansion.

Female genitalia.— Ovipositor long, extending one and one half times its own width beyond pygofer. Pygofer long and narrow.

Posterior margin of seventh sternum broadly rounded without median emargination.

Host plants.— This species has been collected on cottonwood

(Populus deltoides Marsh.).

Type locality.— Alameda Co., California.

Distribution of material examined.-- United States: Arizona.

Remarks.— A total of 23 specimens was examined,

Idiocerus texanus sp. n.

(Figs. 52, 9k, 13U, 187, and 23U)

Resembling amoenus in general appearance, but not highly marked, male antennal disc smaller, and tie male genitalia distinctly different. Length: Male U.6 to U.7 mm, female U.8 to

5.2 mm. Width of head: Male 1.6 to 1.7 mm, female 1.7 to 1.8 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus same width as length; anteclypeus longer than wide, parallel margined. Male antennal disc apical and small.

Forewing flaring, venation obscure, with a large appendix. Color,-- Vertex and face uniformly yellow. Pronotum yellow changing to a yellow brown near posterior margin. Scutellum uniformly yellow brown. Fore wing nearly unicolorus yellow brown.

Male genitalia.— Plate short, arched, narrow, nearly same width to a blunt apex. Pygofer narrow, with a pointed apex. Style arched, nearly pointed at apex, with spines near apex long as well as the apical spines. Connective short, shaped like an inverted

WT", with a median ventral projection. Aedeagus with shaft narrowing to a flattened apex, gonopore subapical on ventral surface, a process on each side of shaft just basal to gonopore; apodeme expanded at apex, with a large dorsal expansion.

Female genitalia.— Ovipositor short, extending slightly more than its own width beyond pygofer. Pygofer short and evenly rounded.

Posterior margin of seventh sternum rounded, with a shallow median emargination*

Host plants.— Unknown*

Holotype male.— Brownsville, Texas, January 2, 1932, E. D.

Ball. Allotype female.— Brownsville, Texas, January 3, 1932,

E. D. Ball. Paratypes.— 3 males, 3 females, same data as holotypej

1 male, same data as allotype; 1 male, U females, Brownsville, Texas,

May 8, 1935, J. N. Khull; 2 females, Brownsville, Texas, May 25,

193U, J. N. Khull. All types deposited in the United States

National Museum Collection.

Remarks.— This species has a very distinctive style which will separate it from the other species related to amoenus. Idiocerus ball! sp. n.

(Figs. 35, 95, 135, 188, and 235)

Resembling amoenus in general appearance, but larger, not as highly marked, and with distinctly different genitalia. Length:

Hale li.8 to 5.0 mm, female 5.1 to 5*5 mm. Width of head: Male

1.7 to 1.8 mm, female 1.8 to 1.9 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus longer than wide; anteclypeus longer than wide, parallel margined. Male antennal disc apical and globular.

Forewing flaring, venation obscure, with a large appendix.

Color.— Vertex and face of female uniform yellow. Vertex of male yellow; face yellow orange, with a median yellow stripe, and a brown stripe through each gena. Pronotum orange mottled with yellow.

Scutellum orange. Forewing uniformly yellow orange.

Male genitalia.-- Plate short, thin, nearly same width throughout, with a blunt apex. Pygofer narrow, with a pointed apex.

Style curved, deeply notched at apex, with long apical Spines.

Connective short, shaped like an inverted "T", with a ventral pointed projection, Aedeagus with shaft narrowing to a flattened apex, gonopore subapical on ventral surface, a lateral process on each side basal to gonopore; apodeme expanded at apex, with only a sLight median dorsal expansion. 77 Female genitalia.— Ovipositor very long, extending nearly three times its own width beyond pygofer. Pygofer long and rounded.

Posterior margin of seventh sternum slightly excavated on either side of a median emargination.

Host plants.— Unknown.

Holotype male.— Sabino Canyon, Arizona, July 29, 1937, E. D. ; > " Ball. Allotype female.— Same data as holotype and on same pin.

Par a type s.— 7 males, 11 females, same data as holotype; 1 female,

Sabino Canyon, Arizona, June 22, 1933, Oman. All types in the

United States National Museum Collection.

Remarks.— This species can be separated from* the other

species related to amoenus by the unusually notched apex of the

style and the very long ovipositor of the female. This species is

named in honor of the late E. D. Ball who collected and described

many Idiocerus.

Idiocerus pyramidatus DeLong and Caldwell

(Figs. 3li, 96, 136, 189, and 236)

Idiocerus pyramidatus DeLong and Caldwell, 1937a, p. 162.

Idiocerus huachncae Ball and Parker, 19U6, p. 80. (new synonymy)

Resembling amoenus in general appearance, but larger, darker

in color, antennal discs of male smaller, and with distinctly

different genitalia. Length* Male 5.2 to 5.5 mm, female 5.3 to

5.6 mm. Width of head: Male 1.7 to 1.9 mm, female 1.8 to 2.0 mm. Vertex evenly rounded, slightly longer near eyes than in middle,

Postclypeus nearly same length as width* anteclypeus longer than wide, slightly expanded at apex. Hale antennae with a small linear disc at apex. Forewing long, flaring, venation nearly obscure, with

a large appendix.

Color.— Vertex yellow, male with two «m»n brown spots about

twice their own width from eyes. Face of male uniformly yellow

except for a wide brown band through each gena; antennal disc black.

Face of female yellow mottled slightly with yellow orange. Pronotum

yellow with large patches of orange, male with dark brown spots along

anterior margin. Scutellum mostly orange, male with dark brown

triangles. Forewing yellow orange with a yellowish white area at

apex of second claval vein.

Male genitalia.— Plate short, narrow, nearly same width to

a blunt apex. Pygofer short, narrow, with a pointed apex. Style

evenly curved to apex, with several short combined spines at apex.

Connective shaped like an inverted "T", with a median ventral

pointed projection. Aedeagus with shaft curved to a flattened apex,

gonopore at basal end of flattened area, with a short process on

each side just basal to gonopore; apodeme expanded at apex without

a median dorsal expansion.

Female genitalia.— Ovipositor short, extending about its own

width beyond pygofer. Pygofer short and evenly rounded. Posterior

margin of seventh sternum broadly rounded with median slightly

produced. 79

Host plants,— This species has been collected on willow

(Salix Bp.).

Type.— Holotype male from Huachuca Mts., Arizona, June 9,

1935, J, N. Knull (DeLong Collection).

Distribution of material examined.-- United States* Arizona,

California, and Utah.

Remarks.— A total of 69 specimens was examined,

Idiocerus concinnus Ball

(Figs. 36, 97, 137, 190, and 237) .

Idiocerus concinnus Ball, 1902, p, 306.

Idiocerus amabilis Ball, 1902, p, 306* Knowlton, 193U, p, 163$

Knowlton, 1935, p. 110; Medler, 191*2, p. 7; Beirne,

1956, p. 2l* (new synonymy)

Idiocerus shivelyanus Bliven, 195U, p. 111*, (new synonymy)

Resembling amoenus in form and general appearance, but much larger, more highly, colored, and with distinctly different genitalia.

Length* Hale £,1* to 6.1 mm, female 5.5 to 6.3 mm. Width of head:

Male 1.8 to 2.0 mm, female 1.9 to 2.1 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus longer than wide, nearly straight margined} anteclypeus longer than wide, expanded at apex. Hale antennal disc large, long, nearly oval. Forewing flaring, venation nearly obscure, appendix large. 80

Color.— Vertex yellow, without spots. Face of male yellow with an orange stripe down median line, and a brown band through each gena; antennal disc black. Face of female uniformly yellow except for an orange band across face above ocelli. Pronotum yellow mottled with orange brown. Scutellum yellow with orange brown markings, male with dark brown triangles. Forewlng yellow with an orange brown area at base of clavus and a smaller one at apex of clavus.

Male genitalia.— Plate curved, narrow, with a blunt apex.

Pygofer narrow, terminating in a nearly pointed apex. Style short, curved to apex, several heavy short spines at apex. Connective shaped like an inverted "T", with a median ventral pointed projection.

Aedeagus with shaft curving to a flattened apex, gonopore at basal end of flattened area on ventral surface, short process on each side just basal to gonopore; apodeme greatly expanded at apex with a median dorsal expansion.

Female genitalia.— Ovipositor long, extending about its own width beyond pygofer. Pygofer broad and evenly rounded. Posterior margin of seventh sternum broadly rounded without a median emargination.

Host plants.— This species has been collected on Salix cordata

Muhl., Salix lucida Muhl., Salix lasiandra Benth., Salix lasiandra var. caudata (Nutt.) Sudw., Salix ? lutea Nutt,, and Sequoia

sempervirens (D. Don) EndL. 81

Type,— A "type” male from Vancouver Island, British Columbia,

August 21* (United States National Museum Collection) is here

designated the lectotype; the genitalia are removed and in a vial

attached to the pin.

Distribution of material examined.— Doited States: California,

Colorado, Idaho, Kansas, Massachusetts, Minnesota, Nevada, New

Mexico, New York, Pennsylvania, Oregon, Utah, Washington, and

Wisconsin. Canadat British Columbia.

Remarks.— A total of 151* specimens was examined.

Idiocerus nervatus Van Duzee

(Figs. 53, 99, 125, 198, and 2l*5)

Idiocerus nervatus Van Duzee, I89I*, p. 205j Gillette and Baker,

3-895* P. 76; Osborn, 1905, p. 506; DeLong, 1916, p. 22;

Lathrop, 1917, p. 8; Lawson, 1920, p. 70; DeLong, 1923,

p. 65; Osborn, 1928, p. 210; Fletcher, 1928, p. 1*1;

Knowlton, 193U, p. 165; Medler, 19l*2, p. 8; DeLong,

191*8, p. 117.

Idiocerus populi. Beirae (not Linne) (in part), 1956, p. 23.

A small pale green species without dark markings. Length:

Male l*.i* to 5.0 mm, female 1*.8 to 5.3 mm. Width of head: Male

1.5 to 1.7 mn, female 1.6 to 1.8 mm. 82

Vertex rounded, nearly sane length In middle as near eyes*

Postclypeus nearly same width as length; anteclypeus longer than wide, expanded at apex. Male antennae with a small circular disc at apex. Forewing flaring, venation obscure except for Epical veins, with a large appendix.

Color.— Vertex and face green, male antennal disc black.

Pronotum and scutellum green. Forewing transparent green, with

appendix sometimes smoky. Specimens fade to yellow in collections.

Male genitalia.— Plate short, thin, wider near apex. Pygofer

short, narrow, with a rounded apex. Style narrowing to a pointed

apex, with several combined spines at apex. Connective shaped like

an inverted nTn, with a pointed ventral projection. Aedeagus with

shaft narrowing to a flattened apex, gonopore on ventral surface at base of flattened area, a short process on each side of shaft just basal to gonopore; apodeme enlarged at apex, with a dorsal

expansion.

Female genitalia.— Ovipositor short, blunt, extending its own width beyond pygofer. Pygofer short and rounded. Posterior margin

of seventh sternum rounded with a shallow median emargination.

Host plants.— This species has been collected on poplar

(Populus deltoides Marsh.), willows (Salix lucida Muhl., Salix

amygdaloides Anders., Salix ? lutea Nutt., Salix lasiandra Benth.,

Salix nigra Marsh., and Salix lasiandra var, caudata (Nutt.) Sudw.),

junipers (Juniperus virginiana L. and Juniperus sp.), and redwood

(Sequoia sempervirens (D. Don) Endl.). 83

Type.— Lectotype male from Lancaster, New York, (June 28,

I889 ), E, P. Van Duzee (Iowa State College Collection); designated by Oman (19U7).

Distribution of material examined.— United States: Arizona,

California, Colorado, Delaware, District of Columbia, Florida,

Idaho, Illinois, Kansas, Mississippi, New Jersey, New Mexico, New

York, Ohio, Tennessee, Texas, Utah, Wisconsin, and Wyoming.

Remarks.— A total of 261 specimens was examined.

Idiocerus taxodium DeLong

(Figs. 55, 101, 126, 199, and 2U6)

Idiocerus taxodium DeLong, 192U, p. 6 3 .

Resembling nervatus in general appearance, but smaller, and with distinctly different genitalia. Length: Male luO to U.U mm,

female U.3 to U.5 mm. Width of head: Male 1.5 to 1.7 mm, female

1.6 to 1.7 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus same width as length; anteclypeus longer than wide,

little expanded at apex. Male antennae with small elongate disc

twice its own length from apex. Forewing flaring slightly, venation

obscure except for apical veins, with a large appendix. Color.— Vertex and face green, eyes red, male antennal disc black. Pronotum and scutellura green. Forewing transparent green, often smoky at apex, with a bright irridescent tinge. Specimens fade to yellow in collections.

Male genitalia.— Plate short, thin, nearly same width to apex.

Pygofer short, narrow, with a pointed apex. Style narrowing to a pointed apex, with several large combined spines at apex. Connective shaped like an inverted "Tw, with a pointed ventral projection.

Aedeagus small, with shaft narrowing to a long flattened apex, gonopore on ventral surface at base of flattened area, a short process

on each side of shaft just basal to gonopore; apodeme enlarged at apex, with a dorsal expansion.

Female genitalia.— Ovipositor short, extending its own width beyond pygofer. tygofer narrow, short, evenly rounded. Posterior margin of seventh sternum rounded with a median emargination.

Host plants.— This species has been collected on bald

cypress (Taxodium dictichum (L.) Richard).

Type.— Holotype male from Paradice Key, FLorida, April 10,

1921, J. N. K n u U and D. M. DeLong (DeLong Collection).

Distribution of material examined.— United States: Florida,

Remarks'.— A total of 66 specimens was examined. 85

Idiocerus rossi sp. n.

(Figs. 51+, 10U, 127, 200, and 21+7)

Resembling nervatus in general appearance, but male antennal

disc larger, and with distinctly different genitalia. Lengths

Male 1+.2 to h.5 mm, female U.U to I+.7 mm. Width of head: Male

1.1+ to 1.6 ram, female 1.6 to 1.7 mm.

Vertex evenly rounded, nearly same length in middle as near

eyes. Postclypeus same width as length; anteclypeus longer than

wide, little expanded at apex. Male antennae short with a large

oval disc. Forewing flaring, venation nearly obscure, with a

large appendix.

Color.— Vertex and face of male yellow green, postclypeus

bright yellow, antennal disc brown with yellow at both ends.

Vertex and face of female yellow green with faint brown spots on

vertex. Pronotum and scutellum yellow green. Forewing transparent

yellow, veins faintly brown near apex.

Male genitalia.— Plate short, thin, wider near apex. Pygofer

short, narrow, with a pointed apex. Style short, narrowing to a

thick but pointed apex, several large spines near apex. Connective

shaped like an inverted "Tn, with a ventral pointed projection,

Aedeagus short, with shaft narrowing slightly to a flattened apex,

gonopore at base of flattened area, a short curved process on each

side of shaft just basal to gonopore* apodeme enlarged at apex, with

a large dorsal expansion. Female genitalia.— Ovipositor short, extending about one and a half its own width beyond pygofer. Pygofer narrow and rounded.

Posterior margin of seventh sternum rounded with a median emargination.

Host plants.— This species has been collected on Salix exigua Eutt.

Holotype male.— Junction City, California, August 21, 1957,

H. H. and J. A. Ross, on #S-5U or Salix exigua Hutt, Allotype female.— Same data as holotype. Paratypes.— 11 males, 8 females,

same data as holotype. All types in the Illinois Natural History

Survey Collection;

Remarks.— This species can be easily separated from nervatus by the unusually large antennal discs and the longer female

ovipositor. I take great pleasure in naming this species after

Dr. H. H. Ross of the Illinois Natural History Survey,

>

Idiocerus musteus Ball

(Figs. 22, 73, 131, 183, and 231)

Idiocerus musteus Ball, 1902, p. 308; Beirae, 1956, p. 2lu

Idiocerus verruscosus Ball, 1902, p. 309. (new synonymy)

Idiocerus utahnus Ball and Parker, 19U6, p. 78. (new synonymy)

A dull brown species, with a pair of small spots on the

vertex. Length: Male 1|.5 to 5*0 mm, female U.7 to 5.3 mm. Width

of head: Male 1.5 to 1.6 mm, female 1.7 to 1.8 mm. Vertex evenly rounded, nearly same length in middle as near eyes, Postclypeus as wide as longj anteclypeus longer than wide, expanded at apex, Male antennae simple, or with a long narrow disc near apex. Forewing flaring, with a large appendix.

Color,-- Vertex yellow, with two round black spots about twice their own width from eyes. Face of male yellow, usually with

dark brown markings between ocelli and spots on vertex. Face of female yellow mottled with brown, Pronotum yellow mottled with brown, males usually with several dark brown spots along anterior margin, Scutellum of male yellow, with black triangles, pair of

spots near median and line down median dark brown. Scutellum of

female same as male but markings light brown. Forewing yellow

brown with brown veins interrupted with yellow,

Male genitalia,— Plate short, thin, nearly same width to apex,

Pygofer short, wide, with a nearly pointed apex. Style arched near

apex, bluntly pointed, with several combined spines at apex.

Connective shaped like an inverted MTrt, with a ventral pointed

projection. Aedeagus with shaft narrowing to a flattened apex,

gonopore apical, a short thick process on each side of shaft just

basal to gonopore; apodeme enlarged at apex, with a dorsal expansion.

Female genitalia.— Ovipositor short, extending a little more

than its own width beyond pygofer. Pygofer short, narrow, evenly

rounded. Posterior margin of seventh sternum evenly rounded with

a slight median emargination. 88

Host plants.— This species has been collected on willows

(Salix padophylla Rydb., Salix ? lutea Nutt., Salix cordata Muhl.,

Salix lucida Muhl., Salix pseudocordata (Andress.) Rydb., and Salix scouleriana Barr.).

Type.— A male "type" specimen from Vancouver Island, British

Columbia, July 10, (Livingston) (United States National Museum

Collection), is here designated the lectotype.

Distribution of material examined.-- United .States: Arizona,

California, Colorado, Idaho, Utah, Washington, and Wyoming.

Canada: British Columbia.

j Remarks.— A considerable amount of variation occurs in the facial color pattern and the size and shape of the male antennal discs of this species, but are genitalically the same. A total of

190 specimens was examined.

Idiocerus obispanus Ball and Parker

(Fig. 227)

Idiocerus obispanus Ball and Parker, 19U6, p. 81.

' Resembling musteus in general appearance, but darker, larger,

and more prominent male antennal discs. Length: Male 5.0 to 5.2

mm, female U.8 to 5.5 mm. Width of head: Male 1.6 to 1.7 mm,

female 1.7 to 1.8 mm. Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus as wide as long; anteclypeus longer than wide, expanded at apex. Male antennae with a long nearly oval disc.

Forewing flaring, with a large appendix.

Color.-- Vertex yellow, with two round black spots about twice their own width from eyes. Face of male yellow, with a brown band down median of postclypeus. Face of female yellow mottled with brown. Pronotum yellow mottled with brown, with many black spots along anterior margin. Scutellum yellow, with black triangles and a pair of spots near middle. Forewing yellow brown, with brown veins interrupted with yellow.

Male genitalia.— The male genitalia of this species is seemingly the same as in musteus.

Female genitalia.— Ovipositor long, extending nearly twice its own width beyond pygofer. Pygofer short, narrow, and evenly rounded. Posterior margin of seventh sternum roundedly produced, with a slight median emargination.

Host plants.— This species has been collected on willows

(Salix sp.).

Type.— Holotype male from San Luis Obispo, California, June,

22, 1931, E. D. Ball (United States National Museum Collection).

Distribution of material examined.— United States: California.

Remarks.— This species is very closely related to musteus but

the different color pattern and female segment will separate them.

A total of 23 specimens was examined. 90

Idiocerus alternatus Fitch

(Figs. U5, 98, 1U6, 191, and 238)

Idiocerus alternatus Fitch, 1851, p. 59; Gillette and Baker, 1895,

p. 73; Osborn, 1905, p. 506; DeLong, 1916, p. 18; Lawson,

1920, p. 66; DeLong, 1923, p. 62* Buys, 192U, p. 13;

Osborn, 1928, p. 210; Knowlton, 193U, p. 16S; Medler,

19U2, p. 9; DeLong, 19U8, p. 122; Beirne (in part),

1956, p. 2U.

Idiocerus interruptus Gillette and Baker, 1895, p. 7U.

Idiocerus coconinus Ball and Parker, 19U6, p. 75. (new synonymy)

Idiocerus renoanus Ball and Parker, 19U6, p. 7 8 . (new synonymy)

. Idiocerus varius DeLong and Hershberger, 19U7, p. U6 (new synonymy)

A brownish fuscous species, with light markings on pronotum and forewings. Length: Male U.8 to 5.1 mm, female 5.1 to 5.5 mm.

Width of head: Male 1.6 to 1.7 mm, female 1.7 to 1.8 ram.

Vertex broadly rounded, nearly same length in middle as near eyes. Postclypeus little longer than wide; anteclypeus longer then wide, expanded at apex. Male antennae with a small circular disc

at apex. Forewing flaring, with a large appendix.

Color.— Vertex yellow brown, with a pair of small black spots

about twice their own width from eyes, and a brown spot near each eye. Face of male yellow, with two nearly parallel brown bars down through postclypeus, brown margin of postclypeus, a dark brown band through each gena, and antennal disc black. Face of female yellow 91 mottled with brown. Pronotum yellow heavily mottled with brown, with black spots along anterior margin. Scutellum of male yellow, with black triangles and black markings along median line. Scutellum of female yellow mottled with brown. Forewing transparent yellow with dark brown veins interrupted with yellow.

Male genitalia.-- Plate short, thin, little wider near apex, lygofer short, curved, with a pointed apex. Style narrowing to a nearly pointed apex, several large combined spines at sqpex.

Connective shaped like an inverted HTW, with a ventral pointed projection. Aedeagus with shaft narrowing to a flattened apex, gonopore at base of flattened area on ventral surface, a short process on each side of shaft just basal to gonopore* apodeme enlarged at apex, with a small dorsal expansion.

Female genitalia.— Ovipositor short, but extending about twice its own width beyond pygofer. Pygofer short, narrow, and evenly rounded. Posterior margin of seventh sternum concavely rounded on each side of a median emargination.

Host plants.— This species has been collected on willows

(Salix lucida Muhl., Salix pseudocordata (Andress.) Rydb., Salix

? lutea Nutt., Salix exigua Nutt., Salix nigra Marsh., Salix amygdaloides Anders., and Salix interior Rowlee) and junipers

(Juniperus virginiana L. and Juniperus sp.).

The type of this species was not seen. 92

Distribution of material examined,-- United States: Arizona,

California, Colorado, Delaware, Idaho, Illinois, Iowa, Maryland,

Michigan, Minnesota, Mississippi, Nevada, New Mexico, North Dakota,

Ohio, Oregon, Pennsylvania, Tennessee, Virginia, Wisconsin, and

Wyoming, Canada: Alberta, British Columbia, and Manitoba,

Remarks.— A total of 512 specimens was examined,

Idiocerus productus Gillette and Baker

(Figs. 38, 87, HiO, 177, and 228)

Idiocerus productus Gillette and Baker, 1895, p. 28* Beime, 1956,

p. 2U,

Resembling alternatus in general color pattern, but larger,

darker, head of male produced, and with distinctly different

genitalia. Length: Male 6.0 to 6.1 mra, female 6.0 to 6.5 mm.

Width of head: Male 1.9 to 2.0 mm, female 2.0 to 2.1 mm.

. Vertex of male produced, longer in middle than near eyes.

Vertex of female evenly rounded. Postclypeus longer than wide;

anteclypeus longer than wide, nearly parallel margined. Male

antennae with a small circular disc near apex. Forewing flaring,

appendix large.

Color.— Vertex of male yellow, with a large median black spot

and a brown streak near each eye. Vertex of female yellow mottled

j with black. Face of male uniformly yellow; antennal disc black.

Face of female yellow mottled with black and brown, but leaving a transverse band across face at level of ocelli nearly unmarked.

Pronotum of male black, spotted with yellow. Pronotum of female mottled with black and brown. Scutellum yellow brown, with black triangles and spots near median line. Forewing brown, apical area yellow brown, with dark brown veins interrupted with yellow spots.

Male genitalia.— Plate long, thin, nearly same width to apex.

Pygofer long, narrow, with a pointed apex. Style greatly arched to

a pointed apex, with several long combined apical spines. Connective

stocky, shaped like an inverted "T", with a ventral pointed projection. Aedeagus with shaft narrowing to a long flattened apex,

gonopore at basal end of flattened area, a process on each side of

shaft at level of gonopore; apodeme enlarged at apex, with a large

dorsal expansion.

Host plants.— Unknown.

Type.— A Hype" male specimen from Leadville, Colorado,

August 23, 189U, C. P. Gillette (Colorado State University Collection)

is here designated the lectotype. -The label on this specimen states*

"Colo. #L7bkn, "type"; and a red cotype label is also attached.

Distribution of material examined.— United States: Alaska,

Colorado, Utah, and Tffyoming. Canada: British Columbia.

Remarks.— The male of this species has a remarkably produced

head which will separate it from all the other species in the genus.

A total of 32 specimens was examined. 9k

IdloceruB aubnitens Saunders and Belong

(Figs. 37, 75, 138, 178, and 210)

Idiocerus subnitens Saunders and Belong, 1917, p. 82; Belong, 19U8,

p. 119.

Resembling productus in general appearance, but vertex of male not produced, and distinctly different genitalia. Length: Male 5.U to 5.7 mm, female 6.1 to 6.2 mm. VfLdth of head: Male 1.9 to 2.0 mm, female 2.1 to 2.2 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus nearly same width as length; anteclypeus longer than wide, parallel margined. Male antennae with a very small apical disc. Forewing flaring, with a large appendix.

Color.— Vertex of male yellow with a pair of small black spots about four times their own width from eyes. Vertex of female yellow with two dark black spots about twice their own width from eyes, a dark brown spot along side each eye, and a dark brown V-shaped mark in middle. Face of male uniform yellow, antennal disc black. Face of female mostly brown, with yellow spots and a dark brown band across face between ocelli and spots on vertex. Pronotum yellow mottled with brown, a few dark brown spots along anterior margin.

Scutellum yellow, with dark brown triangles and spots near middle.

Forewing uniformly brown except for a yellow band across ante apical area, with dark brown veins. Male genitalia.— Plate long, thin, nearly same width to apex.

Pygofer long, narrow, with a nearly pointed apex. Style narrowed to a nearly pointed apex, with several long apical spines. Connective narrow, shaped like an inverted nTn, with a pointed ventral projection, Aedeagus with shaft narrowing to a flattened apex, gonopore at base of flattened area, a process on each side of shaft just basal to gonopore; apodems only aLightly expanded at apex, with

a dorsal expansion.

Female genitalia.— Ovipositor short, extending a little more than its own width beyond pygofer. Pygofer short and evenly rounded.

Posterior margin of seventh sternum roundedly produced.

Host plants.— This species has been collected on poplar and willow.

Type.— Holotype female from Tomab, Wisconsin, August 2, 1916,

D, M. DeLong (DeLong Collection).

Distribution of material examined.— United States: New York,

Vermont, and Wisconsin.

Remarks.— A total of 6 specimens was examined.

Idiocerus delongi sp. n.

(Figs. 28, 70, 130, 175, and 215)

Resembling productus in general appearance, but vertex of male

not produced, ahtennal disc larger, and with distinctly different

genitalia. Length: Male 6.1 mm, female 5*9 to 6.6 mm. Width of

head: Male 2.1 mm, female 2.2 to 2.3 mm. Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus little longer than wide; anteclypeus longer than vide, slightly expanded at apex. Male antennae with a circular disc at apex. Forewing flaring, with a large appendix.

Color.— Vertex yellow, with two black spots about twice their own width from eyes. Face of male uniformly yellow. Face of female mostly brown spotted with yellow. Pronotum brown mottled with yellow and black. Scutellum brown with black triangles. Forewing yellow brown with a wide brown band across middle, veins dark brown interrupted across anteapical area with yellow*

Male genitalia*— Plate long, thin, wider near truncate apex.

Pygofer long, with a pointed apex. Style narrowing slightly to a bluntly pointed apex, with several large combined apical spines.

Connective shaped1 like an inverted wTn, with a pointed ventral projection. Aedeagus with shaft narrowing to a flattened apex, gonopore at apex, long narrow process on each side of shaft just basal to gonopore; apodeme enlarged at apex, with a dorsal expansion.

Female genitalia.— Ovipositor short, stocky, extending slightly more than its own width beyond pygofer. Pygofer short and broadly rounded. Posterior margin of seventh sternum produced with a median emargination*

Host plants.— Unknown.

Holotype male.— Saanich Dist., British Columbia, August 18,

1921, W. Downes. Holotype in the United States National Museum

Collection. 97

Distribution of other material examined.— United States:

California - 2 females, General Grant Park, August 12, 1930j

$ females, Placer Co., August, A. Koebele. Canada: British

Columbia - 1 female, Esqudmalt, September 22, 1927, W. Downes.

Remarks.— I take great pleasure in naming this species for

Dr. D. M. DeLong of The Ohio State University.

Idiocerus obstinatus Ball

(Figs. la, 71, Ui3, 176, and 209)

Idiocerus obstinatus Ball, 1902, p. 310.

Resembling monlliferae in general appearance, but belonging to the alternatns group. Length: Male U.6 to 5.2 mm, female 5.1 to

5.5 mm. Width of head: Male 1.7 to 1.9 mm, female 1.8 to 2.0 mm.

Vertex evenly rounded, nearly same length in middle as near

eyes. Postclypeus longer than wide, with straight margins;

anteclypeus longer than wide, not greatly expanded at apex. Male

antennae with a small nearly round disc at apex. Forewing flaring

with a large appendix.

Color.— Vertex yellow brown with two dark brown spots about

twice their own width from eyes; also an arc of brown over each spot

from eye to hind margin than to median line, darker brown in male.

Face, of male yellow brown with a wide brown band down median line

which is somewhat constricted between ocelli, genae mostly brown,

antennal disc black. Face of female yellow brown with a dark band 98 over ocelli from one antennal ridge to other, small brown band from beneath one ocellus to beneath other, irregular brown circle in middle of postclypeus. Pronotum yellow brown with irregular brown markings, darker in male; but leaving median line unmarked. Scutellum yellow brown with triangles and spots near median line, brown. Forewing smoky brown with brown veins interrupted with yellow.

Male genitalia.— Plate short, narrow, rounded at apex. Pygofer short, narrow, pointed at apex. Style evenly curved to apex, with several combined short spines at apex. Connective shaped like an inverted "T", with a median pointed projection. Aedeagus with shaft narrowing to a rather long flattened apex, gonopore at base of flattened area, a long process on each side just basal to gonopore; apodeme with a moderate expansion at apex.

Female genitalia.— Ovipositor long, extending slightly more than its own width beyond pygofer. Pygofer broadly rounded, robust.

Posterior margin of seventh sternum rounded and slightly produced in middle.

Host plants.— This species has been collected on willow

(Salix sp,).

Type.— A "type" male from Phoenix, Arizona, June, 1897

(United States National Museum Collection) is here designated the lectotype.

Distribution of material examined.— United States: Arizona.

Remarks.— A total of 11 specimens was examined. 99 * Idiocerus couleanus Ball and Parker

(Pigs. UO, 85, 1U2, 181, and 230)

Idiocerus couleanus Ball and Parker, 1?U6, p. 73.

Idiocerus domes! Ball and Parker, 19U6, p. 7U. (new synonymy)

Idiocerus frisearns Ball and Parker, 19U6, p. 7U. (new synonymy)

Idiocerus alternates, Beime (not Pitch) (in part), 1956, p. 2lu

Resembling altematus in general appearance, but larger, darker, and with distinctly different genitalia. Length: Male

5.0 to 5.8 mm, female 5.0 to 6.1 mm. Width of head: Male 1.8 to

1.9 mu, female 1.8 to 2.0 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus nearly as wide as long; anteclypeus longer than wide, expanded at apex. Male antennae with an oval disc at apex.

Forewing flaring, with a large appendix.

Color.-- Vertex yellow mottled with brown,with a pair of black spots about one and a half times their own width from eyes.

Face of male yellow brown greatly patterned with dark brown, antennal disc black. Face of female yellow brown, mottled with brown and dark brown. Pronotum yellow brown mottled with brown, with many black spots along anterior margin. Scutellum yellow brown with black triangles and brown markings along median line.

Forewing mostly smoky brown with dark brown veins interrupted with yellow spots. Male genitalia.-- Plate long, thin, narrow near base then wide near apex. Pygofer long, narrow, with a pointed apex. Style narrowing to a pointed apex, with a single terminal spine at apex.

Connective shaped like an inverted nT", with a ventral pointed projection. Aedeagus with shaft narrowing to a flattened apex, gonopore at base of flattened area on ventral surface, a curved process on each side of shaft at about their own length from apex;

apodeme greatly expanded at apex, with a small dorsal expansion.

Female genitalia.— Ovipositor long, extending about twice

its own width beyond pygofer. Pygofer long, narrow, rounded, with

a slightly enlarged apex. Posterior margin of seventh sternum

rounded, with a slight median emargination.

Host plants.— This species has been collected on willow

(Salix lasiandra Benth.).

Type.— Holotype male from Wellington, British Columbia,

April 16, 1897, (United States National Museum Collection).

Distribution of material examined.— United States:

California, Idaho, and Oregon. Canada: British Columbia. Mexico*

Baja.

Remarks.— A total of 1*0 specimens was examined. 101

Idiocerus femoratus Ball

(Figs. 39, 86, lUl, 180, and 229)

Idiocerus femoratus Ball, 1902, p. 307j Khowlton, 193U, p. 165;

KnowLton, 1935, p. 111.

Idiocerus alternatus, B eime (not Fitch, 1851) ( in part), 1956,

p. 2k,

Resembling alternatus in general appearance, but larger, darker, male with middle femora greatly enlarged, and with distinctly different genitalia. Length: Male 5.2 to 5.5 mm, female 5.3 to

6.1 mm. Width of head: Male 1.8 to 1.9 mm, female 1.9 to 2.0 mm.

Vertex evenly rounded, nearly same length in middle as near eyes, Postclypeus nearly as wide as longj anteclypeus longer than wide, nearly parallel margined. Male antennae short, with a large circular disc near apex. Forewing flaring, -with a large appendix.

Color. ~ Vertex of male yellow with two large black spots about their own width from eyes, dark brown spot between spots and eyes. Vertex of female yellow, speckled with yellow brown, with two black spots about twice their own width from eyes. Face of male yellow, with two parallel brown bars down median line of postclypeus, brown band through each lora, and a brown band through each gena. Face of female yellow speckled with yellow brown.

Pronotum yellow speckled with yellow brown, with a few black spots

along anterior margin. Scutellum yellow brown with black triangles.

Forewing yellow with yellow brown veins interrupted with yellow. 102

Frnnaip genitalia.-- Ovipositor long, extending twice its own width beyond pygofer. Pygofer long and rounded. Posterior margin

of seventh sternum slightly produced with a shallow median

emargination.

Host plants.— This species has been collected on several

species of willow (Salix cordata Muhl. and Sails lasiandra var.

caudata (Nutt.) Sudw.) and alder (Alnus tenuifolia Nutt.).

Type.— The type of this species was not seen.

Distribution of material examined.— United States: California,

Colorado, Idaho, New Mexico, Oregon, Utah, and Washington. Canada:

British Columbia.

Remarks.— The remarkably enlarged middle femora of the male

of this species will separate it from all other species of the genus.

A total of 107 specimens was examined.

Idiocerus ensiger Ball

(Figs. 1:2, 91, 139, 179, and 221)

Idiocerus ensiger Ball, 1902, p. 308j Khowlton, 193U, p. 165*

Idiocerus tenuens DeLong and Caldwell, 1937a, p. 163. (new synonymy)

Idiocerus pacificus Ball and Parker, 191+6, p. 81. (new synonymy)

Resembling altematus in general appearance, but larger,

lighter in color, and with distinctly different genitalia. Length:

Male H.7 to 5.1 mm, female 5.1 to 5.1+ mm. Width of head: Male

1.7 to 1.8 ram, female 1.8 to 1.9 mm. 103

Vertex evenly rounded, nearly same length in middle as near eyes* Postclypeus little longer than wide* anteclypeus longer than wide, not greatly expanded at apex. Hale antennae with a large linear disc at apex. Forewing flaring, with a large appendix.

Color.-- Vertex of male yellow with two brown spots about twice their own width from eyes, a brown streak on each side across the posterior corners near eyes, and a brown V-shaped mark in middle.

Face of male unicolorus yellow. Vertex and face of female yellow mottled with orange, sometimes with brown spots on vertex as in male. Pronotum yellow, male mottled with brown to dark brown, female mottled with orange. Scutellum yellow, male with dark brown triangles and spots, female with orange brown triangles and spots.

Forewing yellow, veins brown interrupted with yellow, base and apex of clavus smoky brown in male and smoky orange in female.

Male genitalia.-- Plate long, narrow, nearly same width to blunt apex. Pygofer stocky with a blunt pointed apex. Style short, curved to apex, with several long combined spines at apex.

Connective shaped like an inverted "TM, with a median ventral projection. Aedeagus with shaft short, curved to a rather long flattened apex, gonopore at base of flattened area, with a process on each side just basal to gonopore; apodeme with a small expansion at apex.

Female genitalia.— Ovipositor very long, extending over three times its own width beyond pygofer. Pygofer long, evenly rounded, with a rugose apex. Posterior margin of seventh sternum nearly straight margined, with a slight median emargination. i o U

Host plants.— This species has been collected from wild current (Kibes sp.) and rabbit brush (Chrysothamnns sp.).

Type.— A female "type” from Dutch George, Colorado, August lli, 1899 (United States National Museum Collection) is here designated the lectotype.

Distribution of material examined.-- United States? California,

Colorado, Idaho, Oregon, Utah, and Wyoming,

Remarks.— A total of 107 specimens was examined.

Idiocerus omani sp. n. \ (Pigs. U3, 8U, Uili, 182, and 222)

Resembling ensiger in general appearance, but darker, and with

distinctly different genitalia. Length* Male U .8 to 5*0 mm, female

5.0 to 5.3 mm. Width of head: Male 1.7 to 1.8 mm, female 1.8 to

1.9 mm.

Vertex evenly rounded, same length in middle as near eyes.

Postclypeus nearly same width as length; anteclypeus longer than

wide, with apex expanded. Male antennae with an oval disc at apex.

Forewing flaring, with a large appendix.

Color.— Vertex yellow, with two round black spots about

twice their own width from eyes, a pair of faint brown streaks near

median, and a brown streak near each eye. Face of male yellow,

antennal disc black. Face of female yellow mottled with brown.

Pronotum yellow mottled with brown, with many black spots along 105 anterior margin. Scutellum yellow, with black triangles and a pair of spots near middle, brown markings down median line. Forewing yellow with brown veins interrupted with yellow, and smoky areas between daval veins, near apex of clavus, and on appendix.

Male genitalia.-- Plate long, thin, nearly same width to blunt apex. Pygofer narrow, with a pointed apex. Style narrowing to a small rounded apex, with several large combined spines near apex. Connective shaped like an inverted "Tn, with a pointed ventral projection. Aedeagus with shaft narrowing to a flattened

apex, gonopore at base of flattened area on ventral surface, a

short process on each side of shaft ju.st basal to gonopore; apodeme enlarged at apex, with a large dorsal expansion.

Female genitalia.— Ovipositor long, extending more than three and a half times its own width beyond pygofer. Pygofer long, evenly rounded. Posterior margin of seventh sternum broadly rounded with a shallow median emargination.

Host plants.— Unknown.

Holotype male.— South of Worden, Oregon, July 1, 1935, Oman.

Allotype female.— Same data as holotype. Paratypes.— 6 males,

6 females, same data as holotype. All types in the United States

National Museum Collection.

Remarks.— This species is very closely related to ensiger

but the rounded apex of the style and the longer ovipositor of the

female will easily separate it. This species is named in honor of

Dr. P. W. Oman who was formerly with the Division of Insect

Identification, United States Department of Agriculture. f

Idiocerus distinctus Gillette and Baker 106

(Figs. U8, 100, 1k9t 1?U, and 2I4I)

Idiocerus distinctus Gillette and Baker, 1895, p. 75.

Resembling altematus in general size and shape, but forewings banded, and with distinctly different genitalia. Length: Male

U.8 to 5*0 mm, female U.8 to 5.2 mm. VBLdth of head: Male 1.5 to

1.6 mm, female 1.6 to 1.7 mm.

Vertex very broadly rounded, nearly same length in middle as

near eyes, Postclypeus longer than wide; anteclypeus longer than

wide, slightly expanded at apex. Male antennae with a small circular

disc at apex. Forewing flaring, venation nearly obscure, with a

large appendix.

Color.— Vertex of male mostly brown, spotted with yellow,

with a pair of black spots about twice their own width from eyes.

Face of male yellow, a pair of faint orange lines through postclypeus

from ocelli to anteclypeus, margins of postclypeus orange, male

antennal disc black. Vertex and face of female yellow mottled with

orange. Pronotum of male yellow mottled with light brown, with

large dark brown spots along anterior margin. Pronotum of female

yellow mottled with orange. Scutellum of male mostly brown with

dark brown triangles. Scutellum of female orange. Forewing

yellow with a brown triangular mark across middle.

Male genitalia.— Plate short, thin, nearly same width to

apex, Pygofer short, curving to a nearly pointed apex. Style

arched, narrowing to a pointed apex, with a single large spine at 107 apex. Connective short, shaped like an inverted "Tn, with a pointed ventral projection. Aedeagus with shaft narrowing to a long flattened apex, gonopore on ventral surface at base of flattened area, a short process on each side of shaft just basal to gonopore; apodeme expanded at apex, with a very small dorsal expansion.

Female genitalia.— Ovipositor short, extending a little more than its own width beyond pygofer. Pygofer narrow and evenly rounded. Posterior margin of seventh sternum concave on either side of a median emargination.

Host plants.— This species has been collected on willow

(Sallx scouleriana Barr.).

Type.— Holotype female from Steamboat Springs, Colorado,

July 15, (Baker), on willow. Type not seen.

distribution of material examined.— United States: 'California,

Colorado, Idaho, Oregon, Utah, and Washington,

Remarks.— A total of 93 specimens was examined.

Idiocerus tahotus Ball and Parker

(Figs. U9, 90, 150, 195, and 2li2)

Idiocerus tahotus Ball and Parker, 191*6, p. 77.

Resembling distinctus in general appearance, but lighter in color, and with distinctly different genitalia. Length: Male li.U to mm, female 1*.6 to it.7 mm. Width of head: Male 1,5 to 1.6 mm, female 1.6 to 1.7 mm. 108

Vertex evenly rounded, nearly same length in middle as near eyes, Postclypeus longer than wide; anteclypeus longer than wide, nearly parallel margined, Male antennae with a small circular disc at apex. Forewing flaring, with a large appendix.

Color.— Vertex yellow brown with a pair of small faint brown spots about three times their own width from eyes. Face of male yellow brown, with a pair of nearly parallel bars down through postclypeus, brown streak down margins of postclypeus, and black antennal discs. Face of female yellow brown mottled with brown.

Pronotum yellow brown mottled with brown, male with a few dark brown spots along anterior margin. Scutellum yellow brown with dark brown triangles and brown along posterior margin. Forewing yellow brown with a wide reddish brown band across middle, smoky brown at base and apical ends, with brown veins interrupted with yellow.

Male genitalia.— Plate short, thin, nearly same width to apex.

Pygofer short, nearly pointed at apex. Style greatly arched to a pointed apex, with several large combined spines at apex. Connective shaped like an inverted MTn, with a ventral pointed projection.

Aedeagus short, with shaft narrowing to a long flattened apex, gonopore on ventral surface at base of flattened area, a short process on each side of shaft just basal to gonopore; apodeme enlarged at apex, with a small dorsal expansion.

Female genitalia.— Ovipositor relatively long, extending about twice its own width beyond pygofer. Pygofer long, narrow, evenly rounded. Posterior margin of seventh sternum rounded with a slight concave emargination on each side of median. 109

Host plants,— This species has been collected on wild current

(Ribes sp.). The type series was collected on red current (Ribes aureum Pursh.).

Type.— Holotype male from Bray, California, June 30, 1935,

P. W. Oman (United States National Museum Collection).

Distribution of material examined.— United States: California,

Oregon, and Washington.

Remarks.— A total of U3 specimens was examined.

Idiocerus morosus Ball

(Figs. U7, 77, 11*8," 193, and 2h0 )

Idiocerus morosus Ball, 1902, p. 309.

Resembles alternatus in general appearance, but smaller, darker, and with distinctly different genitalia. Length: Male U.2 to U.6 ram, female U .6 to 5.2 mm. Width of head: Male 1.5 to 1.6 mm, female 1.6 to 1.7 mm.

Vertex evenly rounded, nearly same length in middle as near eyes. Postclypeus slightly longer than wide; anteclypeus longer than wide, with parallel margins. Male antennae short, with a large circular disc at apex. Forewing flaring, with a large appendix.

Color.— Vertex yellow, with two black spots about twice their own width from eyes, brown spot near each eye, and brown spots along posterior margin. Face of male yellow, with two parallel brown bars down through postclypeus, brown band down both margin of clypeus, a 110 brown band through each gena, and a light brown band under each eye.

Pronotum yellow mottled with brown, with black spots along anterior margin. Scutellum yellow brown, with black triangles and markings

along median line. Forewing yellow brown, -with dark brown veins

interrupted with yellow.

Male genitalia.—- Plate short, thin, slightly wider near apex.

Pygofer short, with a nearly pointed apex. Style curved to a pointed

apex, with several long combined apical spines. Connective shaped

like an inverted nT", with a ventral projection. Aedeagus with shaft

narrowed only slightly to a flattened apex, gonopore subapical at

basal end of flattened area, a short process oh each side of shaft

at level of gonopore; apodeme enlarged at apex, with a dorsal

expansion.

Female genitalia.— Ovipositor long, extending over twice its

own width beyond pygofer. Pygofer long, nearly parallel sided to a

rounded apex. Posterior margin of seventh sternum straight across,

without a median emargination.

Host plants.— This species has been collected on Ribes sp.

Type.— A ”typeM male specimen from Fort Collins, Colorado,

June 13, 1899 (United States National Museum Collection) is here

designated the lectotype.

Distribution of material examined.— United States j Arizona,

California, Colorado, New Mexico, Oregon, Utah, and Washington.

Remarks.— A total of 105 specimens was examined. m

Idiocerus apache Ball and Parker

(Figs. 16, 88, lU7, 192, and 239)

Idiocerus apache Ball and Parker, 19U6, p. 76.

Idiocerus apache var. .juniperus Belong and Hershberger, 19U7,

p. U6; Belong, 19U8, p. 122. (new synonymy)

Resembling altematus but slightly smaller with more pronounced markings and distinctly different genitalia, length: Male U.6 to

5.2 mm, female U.7 to 5.2 mm. Width of head: Male 1.6 to 1.7 mm,

female 1.6 to 1.7 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus longer than wide; anteclypeus nearly parallel sided,

longer than wide. Male antennae with a rounded disc at apex. Male

eighth sternum deeply and widely excavated leaving lateral portions

long and sharply pointed. Forewing flaring slightly, appendix

large.

Color.— Vertex yellowish brown with two small spots about

twice their own width from eyes. Face of male yellow brown with a

brown stripe on each margin of clypeus and a wide brown band through

each gena; antennal disc black. Face of female yellow brown mottled

with brown, a yellow stripe across face just above ocelli. Pronotum

yellow brown mottled with brown, darker brown markings along

anterior margin. Scutellum yellow brown with dark brown triangles.

Forewing smoky brown with brown veins interrupted with yellow,

large yellow spot at apex of second claval vein* 112

Male genitalia.— Plate long, considerably angled, narrow, blunt at apex, fygofer long, narrow, pointed at apex. Style

curving near apex, several long combined spines at apex. Connective

shaped like an inverted "T", with a ventral pointed projection.

Aedeagus with shaft curving to a narrow flattened apex, gonopore

at basal end of flattened area on ventral surface, a short process

on each side at the level of the gonopore; apodeme greatly expanded

at apex with a median dorsal expansion.

Female genitalia.— Ovipositor long, extending slightly more

than its own width beyond pygofer. Pygofer long, narrow, evenly

rounded. Posterior margin of seventh sternum nearly straight

across with a slight indentation on each side.

Host plants.— This species has been collected on Juniper us

Deppeana var. pachyphloea (Torr.) Martinee, gymenoclea salsola

T. & G., and Pluchea sericea (Nutt.) CoviUe.

Type.— Holotype male from Huachuca Mts., Arizona, August 2,

1931, E. D. Ball (United States National Museum Collection).

Distribution of material examined.— United States: Arizona,

California, Colorado, Florida, Qeorgia, Idaho, Illinois, Louisiana,

Maryland, Mississippi, Nevada, New Mexico, North Carolina, Texas,

Utah, Washington, and doming.

Remarks.— A total of 329 specimens was examined. 113

Idiocerus rotundens DeLong and Caldwell

(Rigs. 6, hht 89, 1U5, 18U, and 202)

Idiocerus rotundens DeLong and Caldwell, 1937a, p. 137j Medler,

19U2, p. 9j DeLong, 19U8, p. 121,

Idiocerus verticis. Gillette and Baker (not Say), 1895, p. 80j

Osborn, 1905, p. 507; DeLong, 1916, p. 20; Lawson, 1920,

p. 67; DeLong, 1923, p. 66; Osborn, 1928, p. 210.

A light yellowish brown species with a pair of prominent black

spots on the vertex and large male antennal discs. Length: Male

U.5 to U.8 mm, female h,7 to 5.1 ran. Width of head: Male 1.5 to

1 .6 mm, female 1.6 to 1.7 mm.

Vertex evenly rounded, nearly same length in middle as near

eyes. Postclypeus same width as length; anteclypeus longer than wide, little expanded at apex. Male antennae short, with a large

circular disc at apex. Forewing flaring, with a large appendix.

Color.— - Vertex yellow, brown spot in middle, with a pair of black spots about their own width from eyes. Face of male yellow,

usually with a bright yellow stripe down median of postclypeus,

with a bright yellow band beneath each eye, antennal disc dark

brown with yellow at both ends. Face of female yellow mottled

with brown. Pronotum brown spotted with yellow, with a few dark

brown spots along anterior margin. Scutellum yellow brown with

black triangles. Forewing yellow brown, with brown veins interrupted

with yellow* Ill*

Male genitalia,— Plate long, thin, narrower at base, Pygofer long, narrow, with a bluntly pointed apex. Style thin, narrowing to a pointed apex, several large combined spines at apex. Connective shaped like an inverted IT", with a ventral pointed projection,

Aedeagus with shaft narrowing to a flattened apex, gonopore on ventral surface at base of flattened area, a short process on each side of shaft at the level of gonopore; apodeme enlarged at apex, with a large dorsal expansion.

Female genitalia,— Ovipositor short, but extending about twice its own width beyond pygofer, pygofer short and evenly rounded. Posterior margin of seventh sternum very slightly produced in middle, with a median emargination.

Host plants,— This species has been collected on several species of willow (Salix interior Rowlee, Salix nigra Marsh., Salix exigua

Mutt., and Salix bafaylonica L.) and on red cedar (Juniperus virginiana L,).

Type,— Holotype male from Milwaukee, Wisconsin, July 18, 1916,

D. M. Delong (DeLong Collection),

Distribution of material examined,— United States: Arizona,

California, Colorado, Idaho, Illinois, Indiana, Iowa, Kansas,

Michigan, Minnesota, Missouri, Nebrasks, Nevada, New Mexico, Texas,

Utah, Wisconsin, and Wyoming,

Remarks,— A total of 557 specimens was examined. u 5

Idiocerus cat«-Hnua Ball and Parker

(Figs. 50, 102, 151, 196, and 2l*U)

Idiocerus catalinus Ball and Parker, 19U6, p. 76.

Resembling altematus in general shape and color pattern, but much smaller and with distinctly different genitalia. Length:

Male 3.6 to U*0 mm, female U.O to U.2 mm. Width of head: Male l.U to 1.5 mm, female l.U to 1.6 mm.

Vertex rounded, nearly same length in middle as near eyes.

Postclypeus nearly same width as length; anteclypeus longer than wide, apex slightly expanded. Male antennae with an oval disc at

apex. Forewing flaring, appendix large.

Color.— Vertex yellow brown with two faint brown spots about three times their own width from eyes. Face of male yellow brown with a wide brown band through each gena, antennal disc black. Face of female yellow brown with a conspicuous brown stripe across face i between ocelli and spots on vertex. Pronotum yellow brown mottled

tieh large brown patches, male with dark brown markings on anterior

and lateral margins. Scutellum yellow brown with large brown patches, male with dark brown triangles. Forewing yellow brown with brown veins interrupted with yellow, also basal part brown and a

dark brown saddle across middle.

Male genitalia.— Plate short, narrow, rounded at apex.

Pygofer short, pointed apically. Style short, curved, several

large combined spines at apex. Connective shaped like an inverted wTn, with a median ventral pointed projection. Aedeagus with shaft narrowing to a narrow but flattened apex, gonopore at base of

flattened area on ventral surface, a short process on each side at

level of gonopore; apodeme expanded at apex.

Female genitalia.— Ovipositor short, extending about its own

width beyond pygofer. Pygofer short, indented near apex. Posterior

margin of seventh sternum broadly rounded with a large median

emargination.

Host giants.— Unknown.

Type.— Holotype male from Santa Catalina Mts., Arizona, April

26, 1931, E. 0. Ball (United States National Museum Collection).

Distribution of specimens examined.— United States: Arizona.

Remarks.— A total of 15 specimens was examined.

’ Idiocerus exilus sp. n.

(RLgs. *1 , 103, 152, 197, and 2U3)

Resembling catalinus in general appearance, but lighter in

color, male antennal disc long, and with distinctly different

genitalia. Length: Male U.l to U.2 mm, female U.l to U.3 nm.

Vidth of head: Male l.U to 1.5 mm, female l.U to 1.5 mm.

Vertex evenly rounded, nearly same length in middle as near

eyes. Postclypeus longer than wide; anteclypeus longer than wide,

nearly parallel margined. Male antennae with a long thin disc, and

base also expanded and flattened ventrally. Forewing flaring, with

a large appendix. 117

Color.— Vertex of male yellow with two large black spots about their own width from eyes. Vertex of female same as male except also mottled with brown. Face of male yellow, with a bright yellow band down median line, a brown band through each gena, and antennal disc and basal expansion black. Face of female yellow mottled with brown.

Pronotum yellow mottled with brown, with a few dark spots along

anterior margin. Scutellum yellow with dark brown triangles.

Forewing yellow with brown veins interrupted with yellow.

Male genitalia.— Plate short, thin, wider near apex. Pygofer

short with a bluntly rounded apex. Style narrowing to a nearly pointed apex, with several large combined spines near apex.

Connective shaped like an inverted "Tn, with a pointed ventral projection. Aedeagus small, with shaft narrowing to a flattened

apex, gonopore at base of flattened area, a short process on each

side of shaft just basal to gonopore; apodeme greatly enlarged at.

apex, with a dorsal expansion.

Female genitalia.— Ovipositor short, extending about twice

its own width beyond pygofer. Pygofer short, nearly rounded.

Posterior margin of seventh sternum broadly rounded with a median

emargination.

Host plants.— This species has been collected on white willow.

Holotype male.— Chiricahua Mts., Arizona, October 16, 1931,

E. D. Ball, white willow. Allotype female.— Same data as holotype.

Paratypes.— 2 males, 3 females, same data as holotype. Holotype,

allotype, and one female para type on the same pin; holotype and 118 allotype are the outermost specimens* All types in the United States

National Museum Collection.

Distribution of other material examined*— United States*

Arizona.- Santa Cruz Rv., 2 males, 1 female, April 22, 1932, E. D,

Ball; Patagonia, 1 male, 1 female, May 10, 1931, E, D. Ball* Santa

Rita Mts., 3 males, June 27, 1933, P. W. Oman.

Remarks.— This species has a remarkable disc-like expansion on the ventral side of the base of the male antennae and this alone will separate this species from all others of the genus. INDEX TO 3DIOCERUS SPECIES

(Synonyms are underlines)

adustus (Herrich-Schaeffer) (see stigmaticalis Lewis.) altematus Pitch ------

coconinus Ball and Parker

interruptus Gillette and Baker

renoanus Ball and Parker

Tarius DeLong and Hershberger amabilis Ball (see concinnus. Ball.) amoemus Val Duzee (see amoenus Van Duzee.) amoenus Van Duzee ------

amoemus Van Duzee

pictus Van Duzee

wiyotus Bliven apache Ball and Parker - — - - - - - — — ------

juniperus DeLong and Hershberger apertus DeLong and Hershberger (see nervatus Van Duzee.) balli, new species ------borealis DeLong and Caldwell (see pallidus Pitch.) bovinus Ball and Parker (see cinctus DeLong and Caldwell.) brunneus Osborn and Ball (see ramentosus (Uhler).) 120 callglnosus DeLong and Caldwell (see chisosus DeLong and Caldwell.) catalinus Ball and Parker ------1U> cauteruB Ball and Parker (see snowi snowi Gillette and Baker.) cephalicus Ball and Parker (see rotundens DeLong and Caldwell.) chicanus Ball and Parker (see distinctus Gillette and Baker) chisosus DeLong and Caldwell ------liO

caliginosus DeLong and Caldwell cinctus DeLong and Caldwell $2

boviuus Ball and Parker cingulatus Ball (see rufus Gillette and Baker.) coconinus Ball and Parker (see alternatus Fitch.) co gnatus Fieber ------— ----- 1*9 concinnus B a l l ------79

amabilis Ball

shivelyanus Bliven continuus Ball (see suturalis Fitch.)

' couleanu3 Ball and Parker ------99

dounesi Ball and Parker

friscanus Ball and Parker crataegi Van Duzee ------35 crenatus Germar (see decimnsquartus (Schrank).)

decirausquartus (Schrank) ------33

crenatus Germar

gemmisimulans Leonard and Crosby

germari Fieber

scurra Germar 1 2 1 delongi, new species------95 depictus Ball ------73 distinctus Gillette and B a k e r ------106

chicanus Ball and Parker

nigreris DeLong and Caldwell dolosus B a l l ------38 downesl Ball and Parker (see couleanus Ball and Parker.) duzeei Frovancher — ------61+ ensiger Ball ------102

paclficus Ball and Parker

tenuens DeLong and Caldwell exilus, new species------116 femoratus Ball ------— ------101

tontonua Ball and Parker fitchi Van Duzee------— ------31

maculipennis Fitch formosus Ball ------58 frise anus Ball and Parker, (see couleanus Ball and Parker.) gemmisiinulans Leonard and Crosby (see decimusquartus (Schrank).) germari Fieber (see decimnsquartus (Schrank).) hebetus DeLong and Hershberger (see lachrymalis Fitch.) huachacae Ball and Parker (see pyramidatus DeLong and Caldwell.) incomptus DeLong and Hershberger (see nervatus Van Duzee.) inscriptus Van Duzee (see raraentosus (Uhler).) interruptus Gillette and Baker (see altematus Fitch.) juniperus DeLong and Hershberger (see apache ,Ball and Parker.) labibaeus Bliven (see nervatus Van Duzee.) lachrymalis P i t c h ------$6

hebetus DeLong and Hershberger

rondulus Ball and Parker levis DeLong and Caldwell (see perplexus Gillette and Baker.) lunaris Ball (see suturalis Fitch) maculipennis Fitch (see fitchi Van Duzee) maximus, new species - - - - - — — ----- — - - - - — $9 mimicus Gillette and Baker (see raraentosus (Uhler).) moniliferae Osborn and B a l l ------— ------U7 morosus Ball — ------109 musteus Ball ------86

utahnus Ball and Parker i-

verruscosus Ball nervatus Van Duzee ------— - - - — - 81

apertus DeLong.and Hershberger

incomptus DeLong and Hershberger

labibaeus Bliven

solus DeLong and Caldwell

nigrens DeLong and Caldwell (see distinctus Gillette and Baker.)

nogalinus Ball and Parker (see rufus Gillette and Baker.)

obispanus Ball and Parker ------— _ - — _ — - 88

obsoletus (Walker) (see pallidus Fitch.)

obstinatus B a l l ------97

oraani, new species------10U 123 pacificus Ball and Parker (see ensiger Ball.) pallidus Pitch------— 62

borealis DeLong and Caldwell

obsoletus (Walker)

telus DeLong and Hershberger perplexus Gillette and Baker ------65

levis DeLong and Caldwell pictus Van Duzee (see amoenus Van Duzee.) productus Gillette and Baker ------— ------92 provancheri Van D u z e e ------29 pyramidatus DeLong and Caldwell ------77

huachucae Ball and Parker ramentosus (Uhler) ----- 36

brunneus Osborn and Ball

inscriptu8 Van Duzee

mimicus Gillette and Baker reoanus Ball and Parker (see alternatus Fitch.) rondulus Ball and Parker (see lachrymalis Fitch.) rossi, new species ------85 rotundens DeLong and C a l d w e l l ------113

cephalicus Ball and Parker rufus Gillette and Baker ----- 5l

cingulatus Ball

nogalinus Ball and Parker scurra (Germar) (see decimusquartus (Schrank).) shivelyanus Bliven (see concinnus Ball.)

« 12U snowi Gillette and Baker - - - - - — — - - - - — - - - - - 1|U

snowi Gillette and B a k e r ------U5

cauterus Ball and Parker

raphus, new subspecies ------U6 solus DeLong and Caldwell (see nervatus Tan Duzee.) spinosus Freytag ----- U2 stellaris DeLong and Caldwell (see suturalis Fitch.) stigmaticalis Lewis ------5U

adustus (Herrich-Schaeffer) striolus Fieber ------— 125 subnitens Saunders and DeLong------9U suturalis Fitch ------67

contlnuus Ball

lunaris Ball

stellaris DeLong and Caldwell tahotus DeLong and Parker - - — - — ------107 taxodium DeLong ------83 telus DeLong and Hershberger (see pallidus Fitch.) tenuens DeLong and Caldwell (see ensiger Ball.) texanus, new species - - — - — --- — - 7k totonus Ball and Parker (see femoratus Ball.) utahnus Ball and Parker (see musteus Ball.) vagus Ball ------— 69 varius DeLong and Hershberger (see alternatus Fitch.) verrucosus Ball (see musteus Ball.) wiyotus Bliven (see amoenus Van Duzee.) APPENDIX

One species, Idiocerus striolus. described from a male specimen from Alaska by Fieber in 1868 can not be properly placed at this time. No specimens from Alaska could be placed for certain under this name and the location of the type is unknown. It is therefore thought best to consider this name a nomen dubium until further information is obtained. BIBLIOGRAPHY

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General External Morphology and Terminology

Figure 1.— Idiocerus dolosus, dorsal view.

Figure 2.— Idiocerus dolosus. face.

Figure 3.— Idiocerus dolosus. head and pronotura,

dorsal view.

Figure U . ~ Idiocerus dolosus. forewing.

Figure 5 , ~ Idiocerus duzeei, male antennae.

Figure 6.— Idiocerus rotundens. male antennae.

Figure 7.— Idiocerus apache, male genitalia,

ventral view.

Figure 8.— Idiocerus apache, female genitalia,

ventral view.

135 136

ANTENNAL RIDGE VERTEX .OCELLUS

--EYE--

GEN'A' 0.5 mm. PRONOTUM

ANTENNAE ‘POSTCLYPEUS SCUTELLUM

LORUM ’ANTECLYPEUS

,OUTER ANTEAPICAL ‘ COSTAL AREA .DISCAL CELLS /^CENTRAL CELLS / / .INNER ^ BRACHIAL CELL APICAL VEINS I mm - 4 t h APICAL CELLS

l.mm CLAVAL VEINS : 4 -APPENDIX CLAVAL SUTURE CLAVUS

ANTENNAL SEVENTH STERNUM DISC EIGHTH STERNUM

--“-SUBGENITAL PLATES 0.5 mm PYGOFER '“'PYGOFER O.lmm OVIPOSITOR-- Figures 9-28

Ventral and lateral view of the aedeagus of various species of Idiocerus. All drawn to the same scale.

137 130

0.5 mm 12 10 SPINOSUS DOLOSUS PROVANCHERI FITCHI

/ 16 13 DECIMUSQUARTUS RAMENTOSUS CHISOSUS

20 18 RUFUS 17 COGNATUS MONILIFERAE SNOWI

24 23 22 DUZEEI PALLIDUS MUSTEUS CINCTUS

28 25 ' 26 DELONGI SUTURALIS VAGUS Figures 29-48

Ventral and lateral view of the aedeagus of various species of Idiocerus, All drawn to the same scale.

139 lliO

29 30 v 32 FORMOSUS LACHRYMALIS MAXIMUS AMOENUS

33 ^ 0.5 mm ' 3 4 35 36 OEPICTUS PRAM1DATUS BALL) CONCINNUS

37 v- 38 39 v ' 40 SUBNITENS PRODUCTUS FEMORATUS COULEANUS

42 43 44 OBSTINATUS ENSIGER OMANI ROTUNDENS

46 4 7 ' 48 ALTERNATUS APACHE MOROSUS DISTINCTUS Figures U9-56

Ventral and lateral view of the aedeagus of various species of Idiocerus. All drawn to the same scale.

Figures 57-78

Lateroventral view of the style of various species of Idiocerus. All drawn to the same scale.

u a 49 J 50 51 52 TAHOTUS CATALINUS EXILUS TEXANUS

' 53 0.5mm 54 56 NERVATUS ROSSI TAXOOIUM STIGMATICALIS

62 v 63 PROVANCHERI COGNATUS CRATAEGI RAMENTOSUS DOLOSUS CHISOSUS SPINOSUS SNOWI

0.5mm

67 FITCH CINCTUS DECIMUSQUARTUS RUFUS OELONGI OBSTINATUS

72 75 ^ 7 6 U 7 7 ^ 78 STIGMATICAUS MUSTEUS PERPLEXUS SUBNITENS SUTURAUS MOROSUS VAGUS Figures 79-10U

Lateroventral view of the style of various species of Idiocerus, All drawn to the same scale.

Figures 105«llU

Ventral view of the connective of various species of Idiocerus, All drawn to the same scale. Hill

n )) A 1 ---

^'8, I OJ I PALLIOUS DUZEEI FORMOSUS LACHRYMALIS MAXIMUS OMANI

\ , ) \

:\ V*’! ! (

86 87 88 89 90 COULEANUS FEMORATUS PRODUCTUS APACHE ROTUNDENS TAHOTUS ENSIGER

•V w

93 95 96 AMOENUS DEPICTUS TEXANUS BALL! PYRAMIDATUS CONCINNUS ALTERNATUS

-An'

y

100 .101 " 102 103 104 NERVATUS OISTINCTUS TAXODIUM CA-ALIMIJS EXILUS ROSSIPALLIOUS DUZEEI

C y ) 107 108 109 V III 0.5mm v no 112 VAGUS FITCHI PROVANCHERI DECIMUSQUARTUS MONILIFERAE FORMOSUS LACHRYMAUS MAXIMUS Figures 115-152

Ventral view of the connective of various species of Idiocerus. All drawn to the same scale.

Figures 153-162

Lateral view of the pygofer and plate of various species of Idiocerus. All drawn to the same scale.

Ht5 Hi6

115 116 117 v 118 v 119 VI20 121 122 STIGMATICALIS OOLOSUS CHISOSUS SPINOSUS RAMENTOSUS' CRATAEGl SNOWI COGNATUS

123 0.5mm 125 'U26 127 ^ 128 v 129 v 130 v 131 RUFUS CINCTUS NERVATUS TAXODIUM ROSSI SUTURAUS PERPLEXUS OELONGI MUSTEUS A 132 133 134 135 v 136 137 138 139 140 AMOENUS OEPICTUS TEXANUS BALLI PYRAMIDATUS CONCINNUS SUBNITENS ENSIGER PRODUCTUS A n n 141 142 143 144 145 v 146 v 147 v 148 v 149 FEMORATUS COULEANUS OBSTINATUS OMANI ROTUNOENS ALTERNATUS APACHE MOROSUS OISTINCTUS Q Q Q 150 ^ 151 X /I52 TAHOTUS CATALINUS EXILUS 153 ( RAMENTOSUS

!f \ A \ \ • I I . ! i I { / \ ! I mm 154 ^ 155 ^ w 156 157 V FITCHI PROVANCHERl DECIMUSQUARTUS STIGMATICALIS

: / w ;! V 161 162 6 OOLOSUS CHISOSUS SPINOSUS SNOWI CRATAEGl Figures 163-183

Lainral view of the pygofer and plate of various species of Idiocerus, A n drawn to the same scale. 1U8 \ \ \ » \ \ V i ■ V :

/ Imm 163 ' ' 164 165 166 MONIUFERAE COGNATUS RUFUS CINCTUS

1 r o .

167 166 169 *-• 170 PALLIOUS DUZEEI VAGUS SUTURALIS

\ I

171 172 • 173 174 PERPLEXUS FORMOSUS LACHRYMALIS MAXIMUS

175 176 177 178 OELONGI OBSTINATUS PRODUCTUS SUBNITENS ENSIGER

! ) 180 181 183 u FEMORATUS COULEANUS MUSTEUS Figures l8ii-200

Lateral view of the pygofer and plate of various species of Idiocerus, All drawn to the same scale.

Figures. 2oi-21S>

Ventral view of the female genitalia of various species of Idiocerus, All drawn to the same scale.

1h9 187 188 184 I mm 185 L ROTUNOENS AMOENUS DEP1CTUS TEXANUS BALLI

189 190 191 192 193 PYRAMDATUS CONCINNUS ALTERNATUS APACHE MOROSUS

194 195 196 198 DISTINCTUS TAHOTUS CXTAlllNUS EXILUS NERVATUS

199 201 202 204 TAXODIUM ROSSI RAMENTOSUS ROTUNOENS RUFUS COGNATUS

2 0 6 207 208 2 0 9 210 FITCHI PROVANCHERI CRATAEGl MONILIFERAE OBSTINATUS SUBNITENS

211 212 w 213 215 OOLOSUS CHISOSUS SPINOSUS DELONGI Figures 216-237

. Ventral view of the female genitalia of various species of Idiocerus. A H drawn to the same scale.

151 - V 2 fift- 1! i1 \ ! \/ v ' I mm 220 216 217 w 218 DUZEEI VAGUS DECIMUSQUARTUS SNOWI PALLIOUS

'T f

V

225 222 '• 223 224 LACHRYMALIS MAXIMUS ENSIGER OMANI FORMOSUS

W 229 230 226 227 '228 FEMORATUS COULEANUS MUSTEUS SUTURAUS OBISPANUS PRODUCTUS

235 236 237 232 234 BALLI PYRAMIOATUS CONCINNUS AMOENUS DEPICTUS TEXANUS Figures 238-21*7

Ventral view of the female genitalia of various species of Idiocerus. All drawn to the same scale.

1*3 iSh

I mm 238 . 2 3 9 w 240 241 242 c ALTERNATUS APAGHE M0R0SUS DISTINCTUS TAHOTUS

243 244 245 246 247 EXILUS CATALINUS NERVATUS TAXODIUM ROSSI

» AUTOBIOGRAPHY

I, Paul Harold Freytag, was b o m in Laramie, Warning, December

3, 193U. I received my secondary school education in the University

Elementary and High Schools of Laramie, Vfyoming, and my undergraduate work at the University of Wyoming which granted me the Bachelor of

Science degree in June, 1956. I then entered Graduate School at The

Ohio State University and held the position of a Teaching Assistant.

After completing a year, I then served the next two years in the

U. S. Army. Following this I returned to Graduate School as a

Research Assistant in 1959 and received the Master of Science degree from The Ohio State University in June, I960. I have continued as a

Research Assistant while completing the requirements for the Doctor of Philosophy degree.

I will remain at The Ohio State University for one year as a

Postdoctoral fellow to continue my studies on leafhoppers.

155