2 8 2 5 rn~ 111112.8 2 5 ~~ 11111 . 11111 . Hg,g = 11111 . 32 1.0 ~~ 11111 ~~ IIIII~: 2.2 "- F_ IIIII~ :: ~III~ l.- I:.. .-'- ~~ :: I~ I.. " I.. " --1.1 LoL.:. .... 1.1 '-"''­ -- -- -- -- 11I1I~·8 111111.8 111111.25 11111 1.4 11111 /.6 111111.25 111111.4 IIIII /.6 MICROCOPY RESOLUTION TEST CHART MICROCOPY RESOLUTION nST CHART NATIO~Al BUREAU OF STANDARDS jqH A NATIONAl BUfllAll Of ~TANDAf!D, 1%3 A T_d=N~ ,,: ~:~:;::'~=====A=U=gus=t=;;f UNITED STATES DEPARTMENT OF AGRICULTURE , ViASHINmON, D.C. ~. ,f 'A CLASSIFICATION OF NORTH AMERICA.N AGALLIAN LEAF HOPPERS 1 ",. By P. W. OMA.."', junior entomologist, Dimsio? of Ta:onomy oj Inseds, Bureau oJ Entomology CONTENTS Page Page Introductiou________________._______ 1 The genus Acalliopm KlrkaIdy____. ___._ 8 HistolT__________________•.___.•__•.•___ ._ 2 The genus Aliallia Curtis.____•______.___ 24 Relationships__ . __._.____•••_•••____•.__ 2 The genus ActTat~atlia Klrkl;Jdy______ ~._ 45 Economic importance oC th~ group__ ._.._•._ 3 The genus Agalliana new genus________.•c_ 70 Characters used in the classiflcation_ ••______ 5 Literature cited.. ____________ ••_______ •__ .___ 71 Technic used in the study__. ___•__•...__._._ 6 II1ustrations....._.__ •• _. _____• __ ._•.•______ 74 Key to the genera.__ ••__._.__________ ._ 7 IndeL.___._._._.___._._.__. ___••___________ 93 INTRODUCTION The only preYious stud~v of all the North American species of the genus Agallia was that made by Osborn and Ball in 1898 (28),2 in which 12 species were treated. Since that time various species have been descnbed by Uhler, Baker, Ball, Osborn, Van Duzee, Olsen, and DeLong and Wolcott, and some of the described species have been synonymyzad~ Because of the considerable number of species involved, their great similarity, the lack of published illustrations, and, in many cases, inadequate descriptions, Identification of species has been very uncertain~ Problems ininsect interrelationship, requir­ ing the accurate identification of species in this group, have made necessary an attempt at a revisional study of the classification of these insects, and the present bulletin is an outgrowth of suCh investigations. Since the writer has had little opportunity for personal field obser­ vations, he has necessarily relied on other workers for most of the I The preparation of this bnDetin has been greatly Cacilitated by the a.<sistance rendered by many entomo· logical workers and institutions, without which many of the more difficult problems could not have been solved~ The writer is particularly indebted to H. O ..Barber, of the Bureau of Entomology, E~ D~ Ball, of the UnIversity oC Arizona, and P. B~ Lawson and R~ H. Beamer, of the University of Kansas, for much constructive criticism and many helpful suggestions. The studies here presented have been bl!Jled on several thousand specimens in the U.S. National Museum collection; on more than 5,000 spec!meas Cur· nIshed by the Entomological Museum oC the UnIversity of Kansas through Hungerford and Rear:ler; OD 'Valuable material and host-plant data supplied by E~ D. Bsll, of the University of .Arizona, and''F.~ W. Davis, oLthe sngar~beetleaC-hopper ,laboratory at Salt Lake Olty; and on specimens lent for study by .o~ M. DeLong, of Ohio State University, HerbertOsbom, of the Ohio Biological Survey, H_ L. Dozier and Sam C~ McCampbell, of Coiorado State Oollege, C.E. Olsen, of the AmeriClll! Musenm of Natnral History, D. A. Wilbur, oC Kansas State Oollege oC Agrlcultnreand Applied Sciences, and Harold Morrison and H. O. Barber, of the BllrI'.au. of Entomology. Type examples of various species have been received for study!rom E~ D.Ball, D. M~ DeLong, Herbert Osborn, and O~ E~ Olsen, of the abov&'named Institutions, and !rom E. P. Van Duzee, of the OallCornia Academy of Sciences, and O~ J ~ Drake, oflowa Stete Oollege~ To all these the writer expresses his sincere thanks~ • Itallc numbers in parentheses refer to Literature Cited, p~ 7l~ li'roXl"-33-1 TEciINICAL. BULLETIN 37.2, U.S. DE~. OF .A,.G'i:tICULTURE . r~cJ;ds concerning 1:.ost plants and habitats. The status of some .of 'jhe.iformstreatedremainsin douht, but itis hoped that the studymay be continued and these points decided when more thorough and care­ ful observations are made. mSTORY ,The genus Agallia was erected by Curtis in 1833 (11) to accom­ modate his consobrina. Scott in 1874 (32) placed consobrina Curt. as a synonym 6f puncticeps Germ., tbis being the present statu., -of that species. The chief cha.racters of the original description are as fol­ lows: Rather short and ovate, f:J.ce ovate-i;rigoaate,-head from above forming a very narrow lunule, ocelli 2 in the forehead,--thorax na-rower than the head, transverse-ovate. Osborn and Ball (2B), in their monograph of the North American species, pointed out the existence of three distinct gI"oups within the genus, desirt\ntingthem as groups I, II, and ill. Kirkaldy in 1907 (lB, p. 11,30-31) gave these groups generic rank and applied to them the names AgaUia, Agalliopsis, and Aceratagallia, ,cith consobri'lVL Curt., noveUa Say, and sanguinolenta Prov., respectively, as types. Van Duzee (43) considered these groups as subgenera in the genus Agallia, but Lawson (£2, p. 55-liB) again gave them generic ranking. Because of the very distinct and constant differe!.lces existing between these groups, the writer also has deemed it advisable to treat them as distinct ~enera, rather than to place them under a single name and thus indicate a very close relationship tha,t does not exist. As a result of these studies it has been necessary to describe a fourth, new genus to accommodate species that evidently do not come within the limits of those already established. RELATIONSIDPS The genus Agallia and related genera belong in the subfamily J3ythoscopinae, which is distinguished from other subfamilies of the Cicadellidae by the position of the ocelli, which are always present on the front, below the vertex rather than on the disk of the vertex or the vertex margin, and by the character of the head, which has no dis­ tinct margin or carina between the vertex and the front. The genera treated in this bulletin may be separated from other North American genera of the Bythoscopinae by the following key: 1 Form broad, rather depressed, front somewhat swollen; antennai pits with a distinct overhanging ledge which is transverse or .nearly so. Elytra usually clothed with short setae Bythoscopus and Straganiopsu. Form neither broad nor depressed, or, if so, then antennal pits without overhangin,g ledge. Ledge, when present, not transverse but dis­ tinctlyoblique. Elytra not clothed with short setae ___________ .:__ 2 2 (1) Distance between ocelli distinctly greater than twice the distance from ocellus to eye; antenna! pits deep; elytra broad, apica! cells short M acropsi8 and Oncopsis. Distance between ocelli not over twice the distance from ocellus to eye; antenna! pits shallow___________________ .______________________ 3 3 (1) Elytra with distinct appendices; head, including eyes, distinctly wider than body________________________________ 1diocerus. Elytra without distinct appendices; head not so distinctly wider than bod,y _ _ __ Agalliopsis, Agallia,. Aceratagallia, and Agalliana. '.l'hese ~enera are differ(jntillted on pap;e 7. _ ,\\ · CLASSIFICATION·.OF.A.GALLIAN LEAF'HOPPERS 3 All species of these genera are characterized by the robust form, short, broad vertex, shallow antennal pits, and the absence ofap­ pendices in the elytra. Osborn and Ball distinguished their threa groups by ·differenc~s in the shape of the posterior margiI:; of the vertex, the character of the surface of the pronotum, the fOrIn of the vertex of the nymphs,and the wing venation. Lawson (21, p. 48-50) confirmed the correctness of this basis for segregation when he point­ ed out the ·differences in the internal wale genitalia. The new genus herein described is distinguished by a combination of the above­ mentionedcharactcrs. ECONOMIC IMPORTANCE OF THE GROUP Uatil DeLong and Davidson (12) discussed the common species attacking economic crops in the United States, s(!'nguinolenta was the only species of the Agallia group to attract enough attention a:.; a pest to receive more than an occasional brief reference to its eco­ nomic nnportance. It is therefore safe to state that the damage done by the various species of the group has been greatly under­ estimated or overlooked. This, probably, is due chiefly to two things, the teno.eu<',y to overlook the injury, and the habit of attributing in­ jury, when observed, to sanguinolenta. These leaf hoppers are fre­ quently overlooked entirely because of their duU colors and secretive habits, and the poor condition of a crop may be attributed to drought when in l'eality the plants have been weakened by the great numbers of tiny leaf hoppel'S sucking their sap. Although the group is usually considered as one feeding primarily upon cereal, forage, and truck crops, Ball states that he has found that most of the species, under normal conditions, have as hosts a distinct plant or group of plants, from which they seldom stray. Thus most of the species become pests of economic crops only when their normal hosts are not available, as is Often the case in extensively cultivated regions. .AB Ball (5, p. 50-51), Osborn (23, p. 15), Gibson (16), DeLong and Davidson (12, p. 377), and others have pointed out, the principal p,rops affected are clover, alfalfa, soybeans, and beets, as well as meadow and pasture lands. DeLong and Davidson (12) treated 11 species in their paper, namely, sangwinolenta, cinerea, uhleri, californica, lyrata, bigeloviae, gillettei, quadripunctata, constricta, deleta, and novella, all as members of the genns Agallia.