This dissertation has been 65—13,247 microfilmed exactly as received
JOHNSTON, Donald Earl, 1934- COMPARATIVE STUDIES ON THE MOUTH-PARTS OF THE MITES OF THE SUBORDER ACARIDEI (ACARI).
The Ohio State University, Ph.D., 1965 Zoology
University Microfilms, Inc., Ann Arbor, Michigan COMPARATIVE STUDIES ON THE MOUTH-PARTS OF THE MITES
OF THE SUBORDER ACARIDEI (ACARI)
DISSERTATION
Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University
By
Donald Earl Johnston, B.S,, M.S*
******
The Ohio State University 1965
Approved by
Adviser Department of Zoology and Entomology PLEASE NOTE: Figure pages are not original copy and several have stained backgrounds. Filmed as received.
Several figure pages are wavy and these ’waves” cast shadows on these pages. Filmed in the best possible way.
UNIVERSITY MICROFILMS, INC. ACKNOWLEDGMENTS
Much of the material on which this study is based was made avail
able through the cooperation of acarological colleagues* Dr* M* Andre,
Laboratoire d*Acarologie, Paris; Dr* E* W* Baker, U. S. National Museum,
Washington; Dr* G. 0* Evans, British Museum (Nat* Hist*), London; Prof*
A* Fain, Institut de Medecine Tropic ale, Antwerp; Dr* L* van der fiammen,
Rijksmuseum van Natuurlijke Historie, Leiden; and the late Prof* A*
Melis, Stazione di Entomologia Agraria, Florence, gave free access to
the collections in their care and provided many kindnesses during my
stay at their institutions. Drs. A* M. Hughes, T* E* Hughes, M. M* J.
Lavoipierre, and C* L, Xunker contributed or loaned valuable material*
Appreciation is expressed to all of these colleagues*
The following personnel of the Ohio Agricultural Experiment Sta
tion, Wooster, have provided valuable assistance: Mrs* M* Lange11 prepared histological sections and aided in the care of collections;
Messrs* G. Berkey and C. Robey provided photographic services; and
Dr* C* R. Weaver provided statistical services,
Mr* W. A* Bruce, Department of Zoology and Entomology, The Ohio
State University, assisted in the collection and examination of birds for feather mites during the summer of 196U*
Miss F* Switzer, Secretary of the Institute of Acarology, Ohio
Agricultural Experiment Station, has typed this thesis with care and
patience*
ii Prof. G. W, Wharton has given thoughtful advice and patient en couragement in the preparation of this thesis.
Research contributing to this study was aided by National Science
Foundation Grant G-19325.
iii VITA
November 8, 193U Born - Windsor, Ontario, Canada
1 9 5 7 ...... B.S., Wayne State University, Detroit, Michigan
1957-1960 . . . Teaching Assistant, Department of Zoology, Uni versity of Maryland, College Park, Maryland
1960-1961 . . . Curator, Institute of Acarology, Department of Zoology, University of Maryland, College Park, Maryland
196l ...... M.S., University of Maryland, College Park, Maryland
1961-present . • Curator, Institute of Acarology, and Instructor, Department of Zoology and Entomology, Ohio Agri cultural Experiment Station, Wooster, and The Ohio State University, Columbus, Ohio
PUBLICATIONS
Johnston, Donald E., G. E. Johnston, and D. L. DeQuisti. 1957. Obser vations on Mlcromegistus baksri Tragardh, I9U8 (Acarina : Mesostig- mata : ParantennulidaeyT"an antennophoroid mite occurring on Scar- ites beetles. Joum. Farasit. U3(5-2):35.
______. 1959. On the status of Casey’s species of Procu- lus (Passalidae). Coleop. Bull. 1111:12^-126,
Baker, E. W. and D. E. Johnston. 1959. Laelaptonyssus phytoseiodes, a new species of laelaptonyssid mite from Hemiptera (Acarina, Mesostigmata). Proc. Ent. Soc. Wash. 6l(6):275-277.
Johnston, D. E. I960. Laelaptid mites associated with hermit crabs (Paguridea) • The genera Aspidilaelaps and Cyclothorax (Acarina - Mesostigmata) • Acarologia II(U):lih2-lih6.
• I960. Some new synonymy in the Haemogamasidae, Lae- laptidae and Diplogyniidae indicated by an examination of Banks’ types of Mesostigmata (Acarina). Psyche 66(U):60-62.
iv Johnston, D. E« 1961. A review of the lower uropodoid mites (former Thinozerconoidea, Protodinychoidea and Trachytoidea) with notes on the classification of the Uropodina (Acarina). Acarologia III(U):522-5U5.
and D. L. DeGuisti. 1961. Ecological and systematic notes on some chigger-mites of the genera Gahrliepia, Trombicula, and Euschongastia (Acarina : Trombiculidae) in Michigan and Ontario. Journ. Parasit. 1;7(1):11-12.
______. 1962. Ixodorhynchine mite ectoparasites of snakes. I. Descriptions of a new genus and three new species from the Nearc tic region (Acarina-Mesostigmata). Bull. Ann. Soc. Royale Ent. Belgique 98(11):235-239.
Fain, A. and D* E. Johnston. I96U. Notes sur le genre Psoralges Trouessart, I896 avec description d'une espece nouvelle. Bull. Ann. Soc. Royale Ent. Belgique 100(31;) :U53-U6l.
Johnston, D. E. I96U. Psorergates bos, a new mite parasite of domestic cattle (Acari-Psorergatidae). Ohio Agr. Expt. Sta. Res. Circular 129:1-7.
. I96U. Discovery of a new mite parasite of cattle in the United States. Pesticide News XVII(k):120, 122.
. I96U. The principles of numerical taxonomy and their application to the systematics of Acari. Proc. First Int. Conf* on Acarology. Acarologia Vl(h.s.):117-126.
. 1961;. Review of "Advances in Acarology," Vol. I (J. Naegele, Ed.), Bull. Ent. Soc. Amer. 10(3):203.
______and A. Fain. 196U. Ophiocelaeno sellnicki, a new genus and species of Diplogyniidae associated with snakes (Acari- Mesostigmata). Bull. Ann. Soc. Royale Ent. Belgique 100(6): 79-91.
, W. Knulle, G. W. Wharton, C* R. Outright, H. T. Forsythe, R. B. Neiswander, and R. W. Rings. 1961;. Comment on: Boudreaux, H. B. and G. Dosse. 1963. Request for Acarus telarius Linne, 1758, Trombldium tiliarium Joh. Hermann, l8oU, Tetranychus urticae Koch, 1836, to be placed on the Official List (Arachnida, Acarina). Z.N.(S.) 1561;. Bull. Zool. Nomencl. 20(5)-.363-366. Bull. Zool. Nomencl. 21(2):107.
v Johnston, D. E. 196$. A catalog of the determined species of Acari (excl. Ixodides) in the collections of the Institute of Acarology. Ohio Agr. Expt. Sta. Dept, of Zool. and Ent. Publ. Series 29: i-v, 1-66.
FIELDS OF STUDY
Major Field: Zoology
Adviser: Professor G. W. Wharton TABLE OF CONTENTS Page
ACKNOWLEDGMENTS ...... ii
VITA ...... iv
TABLE OF CONTENTS ...... vii
LIST OF TABLES ...... ix
LIST OF ILLUSTRATIONS ...... x
INTRODUCTION ...... 1
HISTORICAL ASPECTS ...... 9
MATERIALS, METHODS, AND TERMINOLOGY...... Ik
MATERIALS ...... H
METHODS ...... 29
TERMINOLOGY...... 31
THE MOUTH-PARTS OF CALOGLYPHUS BERIESEI (OUDEMANS) (ACARIDAE) .. 32
THE GNATHQSQMA OF THE HQMEGMORPHIC STASES ...... 33
THE GNATHOSQMA OF THE HETERQMORPHIC DEUTONYMPH...... 1*0
COMPARATIVE STUDIES ...... k2
THE RELATION OF THE GNATHOSQMA AND IDIOSOMA...... 1*2
THE CHELICERAE ...... h2
THE SUBCAPITULUM...... h9
THE PALPS ...... 55
THE GNATHOSGMAL STRUCTURES OF THE HETERGMORPHIC DEUTONYMPHS ...... 58
vii Page
DISCUSSION ...... 61
INTERPRETATION OF THE ANATOMY OF THE GNATHOSQMA AND COM PARISON OF ITS STRUCTURE WITH THAT OF OTHER ACARIFORM MITES ...... 61
INTERPRETATION OF THE COMPARATIVE STUDIES ...... 6?
SUMMARY ...... 76
APPENDIX I: THE MOUTH-PARTS OF PARALYCUS WOMERSLEY ( = FEDICULOCHELUS LAVOIPIERRE) (PEDICU- LOCHELIDAE) ...... 79
APPENDIX II: GLOSSARY OF SOME TERMS PERTAINING TO THE MOUTH- PARTS OF THE ACARIDEI AND OTHER ACARIFORM MITES .. 83
APPENDIX III: LIST OF ABBREVIATIONS USED IN FIGURELABELS ..... 87
FIGURES ...... 90
REFERENCES CITED ...... 18?
viii LIST OF TABLES
Table Page
1 Synonymy of some terms pertaining to the gnathosoma of Acaridei...... 12
2 Allometric constants for idiosomal length (X) and cheliceral length (Y) in 3 species of Falculi- feridae ...... U8
±x LEST OF ILLUSTRATIONS
Figure Page
1 Caloglyphus berlesei (Michael) (ACARIDAE). Anterior region of body of protonymph; l a t e r a l...... 90
2 Caloglyphus berlesei. Chelicera of male; paraxial ..... 92
3 Caloglyphus berlesei. Chelicera of male; antiaxial .... 92
U Caloglyphus berlesei. Chelicera of male, showing musculature; antiaxial ...... 92
5 Caloglyphus berlesei. Subcapitulum of female; dorsal ... 9h
6 Caloglyphus berlesei. Subcapitulum of female; ventral .. 96
7 Caloglyphus berlesei. Cheliceral dentition of male; antiaxial ...... 96
8 Caloglyphus berlesei. En face view of distal portion of subcapitulum of female ...... 100
9 Caloglyphus berlesei. Labrum and phaiynx of female; sagittal section ...... 102
10 Caloglyphus berlesei. Lateral lips and pseudorutella; transverse section ...... 102
11 Caloglyphus berlesei. Subcapitulum of female; trans verse section at levelof pharynx ...... 10li
12 Caloglyphus berlesei. Subcapitulum of female; posterior ...... 106
13 Caloglyphus berlesei. Palp of female; dorsal ...... 108
ll; Caloglyphus berlesei. Extrinsic musculature of palp of female; ventral ...... 108
15 Caloglyphus berlesei. Gnathosoma of deutonymph; dorsal . 110
x Figure Page
16 Caloglyphus berlesei. Gnathosoma of deutonymph- v e n t r a l ...... 110
17 Acarus farris (Oudemans) (ACARIDAE). Anterior region of body of female; lateral ...... 112
18 Bdellorhynchus polymorphus Trouessart (FALCULIFERIDAE). Region of coxa I, subcapitulum, and base of chelicera of male; lateral ...... llU
19 Schwiebia sp. (ACARIDAE). Gnathosoma (partial) of female; lateral...... 116
20 Glycyphagus destructor (Schrank) (GLYCYPHAGIDAE). Chelicera of female; paraxial ...... 116
21 Chortoglyphus arcuatus (Troupeau) (CHORTOGLYPHIDAE). Chelicera of female; paraxial ...... 118
22 Dermatophagoides passericola Fain (PYROGLYPHIDAE). Chelicera of female; paraxial...... 118
23 Carpoglyphus lactie (Linnaeus) (CARPOGLYPHIDAE). Chelicera of female; paraxial ...... 120
21; Ewingia cenobitae Pearse (EWINGIIDAE). Chelicera of female; antiaxial...... 120
25 Histiostoma polypoid. (Oudemans) (ANOETIDAE). Chelicera of female; paraxial...... 122
26 Hemisarcoptes malus (Shimer) (HEMISARCOPTIDAE). Chelicera of female; antiaxial ...... 12U
27 Linobia coccinellae (Scopoli) (UNOBIIDAE). Chelicera of male; paraxial...... 12ii
28 Dermoglyphus elongatus (Megnin) (DERMOGLYPHIDAE). Chelicera of female; paraxial ...... 126
29 Syringobia chelopus Trouessart and Neumann (SYRINGO- BIIDAE). Chelicera of female; paraxial ...... 128
30 "Pteronyssus11 simplex Haller (PTERONYSSIDAE). Chela of female; paraxial...... 130
xi Figure Page
31 Bychovskiata n. sp. (PTEROLICHIDAE). Chela of female; paraxial ...... 130
32 Ardeacarus ardeae (Canestrini) (PTEROLICHIDAE). Chela of female; paraxial ...... 132
33 Psoralges libertus Trouessart (PSOROPTIDAE-Psoralginae). Chela of female; antiaxial ...... 132
3U Proctophyllodes quadrisetosus Atyeo and Braasch (PROCTOPHYLLODIDAE). Chela of female; paraxial ...... 13U
35 Bdellorhynchus polymorphus Trouessart (FALCULIFERIDAE)• Chelicera of male; paraxial...... 13U
36 Falculifer rostratus (Buchholz) (FALCULIFERIDAE). Chelicera of female; paraxial ...... 136
37 Falculifer rostratus. Chelicera of polymorphic male; paraxial ...... 138
38 Otodectes cynotis (Hering) (PSOROPTIDAE-Chorioptinae). Chelicera of male; paraxial ...... lUO
39 Psoroptes cuniculi (Delafond) (PSOROPTIDAE-Psoroptinae). Chela of female; antiaxial ...... li|0
UO ^yocoptes musculinus (Koch) (MYOCOPTIDAE). Chela of female; paraxial...... XU2
Ul Listrophorus dozieri Radford (LESTROPHORIDAE). Chelicera of male; paraxial ...... U;2
U2 Chirodiscoides caviae Hirst (LISTROPHORIDAE). Chela of female; paraxial...... ll;2
U3 Notoedres cuniculi (Gerlach) (SARCOPTIDAE). Chelicera of female; paraxial ...... lhh
I4I4. Knemidocoptes mu tans (Robin) (KNEMIDOCOPTIDAE). Chelicera of female; antiaxial...... lUi
US Pneumocoptes penrosei (Wiedman) (PNEUMOCOPTIDAE). Chelicera of female; paraxial...... llU;
xii Figure Page
1+6 Glycyphagus destructor (Schrank) (GLYCYPHAGIDAE). Subcapitulum of female; v e n t r a l ...... ll+6
1+7 Dermatophagoides passericola Fain (PYROGLYPHIDAE). Subcapitulum (partial) of female; ventral ...... ll+6
1+8 Linobia coccinellae (Schrank) (Linobiidae). Sub capitulum of female; ventral ...... 31+8
1+9 Histiostoma polypori (Oudemans) (ANOETIDAE), Sub- capitulum of female; ventral ...... 150
50 Proc tophyllodes quadrisetosus Atyeo and Braasch (PROCTOPHYLLODIDAE). Subcapitulum of female; ventral ...... 15?
51 Bdellorhynchus polymorphus Trouessart (FALCULIFERIDAE). Subcapitulum of male; ventral ...... 151+
52 Dermoglyphus n. sp. (DERMOGLYPHIDAE). Subcapitulum of female; ventral ...... 156
53 Yunkeracarus faini Hyland and Clark (YUNKERACARIDAE). Subcapitulum of female; ventral ...... 156
51+ Cytonyssus andrei Fain (CYTODITIDAE). Gnathosoma of female; ventral ...... 158
55 Cytodites nudus (Vizioli) (CYTODITIDAE). Gnathosoma of male; d o r s a l ...... 158
56 Cytodites nudus. Gnathosoma of male; ventral ...... 158
57 Rhynchoptes anastosi (Fain) (RHYNCHOPTIDAE). Gnatho- soma, trochanter I, and anterior region of propodo- soma of female;ventral ...... 160
58 Mortelmansia longus Fain (LEMURNYSSIDAE). Gnathosoma (and anterior portion of prodorsum) of female; dorsal...... 162
59 Mortelmansia longus. Gnathosoma (partial) of female; ventral ...... 162
60 Opsonyssus brutsaerti (Fain) (GASTRONYSSIDAE )• Gnatho- soma and prodorsal shield of male; dorsal...... 161+
xiii Figure Page
61 Opsonyssus asiaticus Fain (GASTRONYSSIDAE). Lateral subcapitular apophysis of female; ventral ...... 166
62 Opsonyssus phyllorhinae Fain. Same as above ...... 166
63 Opsonyssus eidoloni Fain. Same as a b o v e ...... 166
61; Opsonyssus zvimpti Fain. Same as above ...... 166
65 Psoroptes cuniculi (Delafond) (PSOROPTIDAE-Psoropt- inae). Pseudorutellar process of female; ventral ..... 168
66 Psoroptes cuniculi. Palp of female; ventral ...... 168
67 Psoroptes cuniculi. Subcapitulum of female; ventro lateral ...... 168
68 Psoroptes cuniculi. Labrum of female; dorsal ...... 168
69 Nycteriglyphus bifolium Strandtmann (ROSENSTEINIIDAK). Pseudorutellar processes of female; v e n t r a l ...... 170
70 Mydopholeus capillus McDaniel and Baker (ROSENSTEINI- IDAE). Pseudorutellar processes of female; ventral ... 170
71 Tyrophagus putrescentiae (Schrank) (ACARIDAE). Palp of female; ventral ...... 172
72 Glycyphagus domesticus (Degeer) (GLYCYPHAGIDAE). Palp of female; antiaxial...... 172
73 Schoutedenocoptes aquilae Fain (TURBINOPTIDAE). Palp of male; ventral ...... 17U
7U Histiostoma polypori (Oudemans) (ANOETIDAE). Palp of female; dorsal ...... 17it
73 Coleopterophagus procerus Berlese (CANESTRINIIDAE). Tip of palp of female; v e n t r a l ...... 176
76 Dermatophagoides passericola Fain (PYROGLYPHIDAE). Same as above ...... 176
77 Chortoglyphus arcuatus Troupeau (CHORTOGLYPHIDAE). Same as above ...... 176
xiv Page
Megniniella gallinulae (Buchholz) (ANALGESIDAE), Tip of palp of female; ventral ...... 176
Caloglyphus sp. (ACARIDAE). Gnathosoma of deutonymph; ventral ...... 178
Cosmoglyphus sp. (ACARIDAE). Gnathosoma of deutonymph; ventral ...... 178
Bonomia sphaerocerae Vitzthum (ANOETIDAE). Gnatho soma of deutonymph; ventral ...... 180
Myianoetus muscarum (Linnaeus) (ANOETIDAE). Gnatho soma of deutonymph; ventral ...... 180
Histiostoma himalayae (Vitzthum) (ANOETIDAE). Gnatho soma of deutonymph; ventral ...... 180
Kennethiella trisetosa (Cooreman) (ENSLINIELLIDAE). Anterior portion of prodorsum of deutonymph; ventral . 182
Labidophorus sp. (LABIDOPHORIDAE). Gnathosoma of deutonymph; ventral ...... 182
Palaeacarus appalachicus Jacot (Palaeacari: PALAE- ACARIDAE). Chelicera of female; paraxial ...... 18U
Palaeacarus appalachicus. Palp of female; antiaxial ... 18U
Palaeacarus appalachicus. Subcapitulum (partial) of female; ventral ...... 186
Protokalumma depressum (Banks) (OribateijPARAKALUMMI- DAE). Subcapitulum of female; ventral ...... 186
Paralycus raulti (Lavoipierre) (Endeostigmata:PEDICU- LOCHELIDAE). Chela of female; antiaxial ...... 188
Paralycus raulti. Subcapitulum of female; ventral .... 188
xv INTRODUCTION
The Recent Arthropoda represent a grade of structural organization that comprises three major groups: the Hexapoda- Myriapoda, the Crus tacea, and the Chelicerata. A disproportionately greater amount of taxonomic and anatomic endeavor has been directed toward the former two groups than toward the latter. The Chelicerata includes the
Merostomata, Arachnida, and, perhaps, the Pycnogonida (or Bantopoda).
Of these, the dominant group is the Arachnida. The largest and most diverse group of Arachnida is the Acari, or mites. While there seems to be no question of a close relationship of Acari and other Arachnida, the mites provide exceptions to most of the anatomical and ecological statements proposed for the Arachnida in general. The trends away from the terrestrial, predaceous, arachnid way of life have resulted in the Acari coming to the special attention of man through the de struction of crop plants and stored food and the parasitism of and disease transmission to man and domesticated animals. This inter ference with human activities has led to increased specialized study of mites, that is, the development of acarology as a separate disci pline. These intensive, specialized efforts have made the mites, in some respects, the best studied of arachnids. At the same time, the diversity and great number of species of Acari makes them the least known of Arachnida.
1 The consolidation of certain elements of the head and first two pairs of appendages into a distinct anatomical region, the gnathosoma or mouth-parts, is a primary feature of the Acari, Despite the im portance of an understanding of the structure of this functional unit and despite its potential importance as a source of taxonomic characters useful at all levels, the gnathosoma is relatively poorly studied. This lack of study is nowhere seen so plainly as in the literature relating to the mites of the suborder Acaridei, The dearth of information on the mouth-parts of these mites leaves a large gap in the already limited data available for students of acarine taxonomy and comparative anatomy.
The effect of this absence of comparative studies has been several-fold:
1, It has weakened the general treatments of Acari such as those of Vitzthum (1931, 19hO-U3), Andre (19U9), Baker and Vlharton (1902),
T, E, Hughes (1959), and Evans, Sheals and Macfarlane (1961),
2, It has contributed to the confusion surrounding the relation ships of the Acaridei with other mite groups,
3, It has certainly limited the number of characters available for consideration of intra-group relationships. The tendency to base classifications on one or a few characters has typified the taxonomic history of the Acaridei,
U. Further, the lack of comparative study has discouraged the inclusion of all but the most cursory data on the anatomy of the gnathosoma in descriptions of acaridid mites.
The purpose of this study is to describe the variation in the mouth-parts of acaridid mites and to interpret this variation in 3 terms of what is known concerning the relationships and lifeways of these mites.
The mites of the suborder Acaridei may be characterized in the following way (statements about mouth-parts omitted): acariform mites; generally with the cuticle poorly sclerotized, especially on the hys- terosoma; the prodorsal and coxal shields are the most typical sclerites although others may occur; respiratory tracheae lacking; with a cuticu- lar process, Grandjean's organ (delta), flanking the gnathosoma; with a prodorsal chaetotactic pattern of four basic pairs of setae; supracoxal glands present, opening at base of podocephalic sclerite above leg I; supracoxal seta (elc I) of leg I usually present, often striking in form; paired latero-opisthosomal glands usually present; Claparede's organ may be present (presence generally, but not absolutely, corre lated with development of genital papillae); coxal setation character istic: 1-0-1-1; two pairs of genital setae; genital papillae generally present in free-living species, reduced or absent in parasitic species
(when present developmental pattern as follows: 0-1-2-2-2 or O-l-x-2-2); female genital opening usually covered by paired paragynial shields whose medial edges together give the appearance of an inverted "Y"; female with a bursa copulatrix opening at rear of body; male genital apparatus with a sclerotized ade&gus; male often with adanal and tarsal
(usually leg IV, rarely leg I) copulatory discs; leg chaetotaxy dis tinctive, generally of a reduced endeostigmatid-orlbatid pattern; seta tion of legs IV shows protonymphal regression; legs essentially ambula tory in function but often modified for sexual coupling in males; femora k undividedj development of fourth pair of legs delayed or suppressed in some parasitic species; tibial solenidia usually long, whip-like; lat eral ambulacral claws absent, central or empodial claw may be present; prodorsal and pedal trichobothria absent. Oviparous or (rarely) ovovi- viparous; life cycles consist of an egg, a larva, a protonymph, a deuto nymph (apparently not obligatory; facultative in many species, entirely absent in others), a tritonymph, and adult. Free-living scavengers; occasional plant-feeders; a few in fresh-water and marine habitats; predators of insects; nest associates of social and solitary insects, birds, and mammals; external parasites of arthropods; external and in ternal parasites of birds and mammals; some species cause tremendous losses in stored food products and others cause mange and scabies in birds and mammals, Deutonymphs usually phoretic (especially on in sects, some on mammals); a few species endoparasitic in birds.
The nature of arthropod development is particularly well fitted for the evolution of ontogenetic polymorphism, or heteromorphy. Along with the Insecta and Crustacea, the Acari have made elaborate use of this potential and, in the acariform mites, heteromorphy has evolved in ail of the major groups. In the Acaridei the best known and most common instance of ontogenetic polymorphism is that displayed by the heteromorphic deutonymph (or as it is usually termed, the hypopus).
In this situation the larva, protonymph, tritonymph, and adult are homeomorphic. By homeomorphic it is meant that these stases are simi lar in anatomical detail except for the changes that characterize nor mal development: increase in size, addition of legs IV, additions in chaetotaxy, increase in sclerotization, and development of genital structures, and that this pattern of development more nearly resembles a primitive state than do the characters of the heteroraorphic stasis,
Acaridid deutonymphs are characterized by extensive or complete scle rotization of the prodorsum and notogaster; modification of the form of the dorsal setae; sclerotization of the venter through hypertrophy of the coxae; the presence of a "sucker plate," considered to be de rived through modification of the perianal setae (Grandjean, 1935a;
Knulle, 1959), or a clasping plate in the case of mammal-associated forms; changes in the form of the legs and in the leg chaetotaxy; and reduction of the gnathosoma.
The deutonymphal stasis may be facultatively present or entirely absent; when it does occur it is always heteromorphic. Hypopi have been recorded for various species in the families Acaridae, Anoetidae,
Carpoglyphidae, Chaetodactylidae, Ensliniellidae, Falculiferidae, Fus- acaridae, Glycyphagidae, Labidophoridae, Lardoglyphidae, and Ptero- lichidae. The inclusion in this list of the Carpoglyphidae is based on Obussier's (1939) description of the hypopus of Carpoglyphus lactis
(Linnaeus) and on the discovery of the hypopus of an undescribed genus
(new genus "H") of this family. The record of a hypopus of Fusacarus is that of Grand jean (1953). A detailed treatment of the hypopi of the
Palaearctic species of Acaridae, Chaetodactylidae, Glycyphagidae, and
Labidophoridae is included in Zakhvatkin (19U1). Baker and Cunliffe
(I960) have reviewed the hypopi of Ensliniellidae. Hypopi of Anoetidae have been reviewed by Scheucher (1957) and R. 0. Hughes and Jackson (1958). Dubinin (1956) has dealt with the few deutonymphs known for
the feather mite families Falculiferidae and Pterolichidae• Although acarologists have been aware of the striking modifications of the mouth-parts of acaridid deutonymphs for over one hundred years (e.g.,
Dujardin's 181*9 work, "Memoire sur les Acariens sans bouche dont a fait le genre Hypopus . . .")> there is little critical work on the exoskele-
tal ana tony of this structural unit or the homologies of its components with the mouth-parts of the homeomorphic stases.
In addition to heteromorphy involving the deutonymph, there are cases where other stases are involved. One moderately well-documented situation is that of Myialges macdonaldi (Ifyialgesidae), described by
Evans, Fain, and Bafort (1963). In this species the larva, protonymph,
tritonymph (a deutonymph is unknown), and adult male are skin-dwellers.
These stases greatly resemble Sarcoptidae (and would probably be identi
fied as such by most taxonomists). The mouth-parts resemble those of
Sarcoptes. The adult females (the heteromorphic stasis) differ markedly
in details of the mouth-parts, legs, and idiosoma. The chelicerae and
subcapitulum are elongate and of a piercing type. Unfortunately, Evans
et al. did not describe the mouth-parts of these mites in any detail.
Dubinin (1953) has described the heteromorphic tritonymph (teleo-
nimfa of Russian workers) of Microlichus avus (Trouessart). This
stasis, described in 1887 as Heteropsorus pteroptopus by Trouessart
and Neumann, displays such striking characteristics that it was placed
in a separate family, Heteropsoridae, until Dubinin's revision. It is not at all clear from Dubinin*s work, however, whether the mouth-parts of the tritonymph differ from those of other stases.
Inter- and intrasexual polymorphism also occurs in the Acaridei.
The most usual instance is that of intersexual polymorphism, or sexual dimorphism. This type of polymorphism is seen in various characters of the legs, idiosomal sclerites, caudal processes, and, in a very few in stances, the mouth-parts. What is probably the most striking case in volving the mouth-parts is that seen in the feather mites of the family
Falculiferidae. In genera such as Falculifer and Bdellorhynchus the chelicerae of the nnormaln males resemble those of the females. Poly morphic males have enlarged chelicerae that are quite different in form from those of the female and normal males. This is, therefore, an ex ample of both inter- and intrasexual polymorphism.
The previously cited example of Myialges is a case of intersexual, as well as ontogenetic, polymorphism.
The place and rank of the Acaridei in a modern system of the Acari may be seen from the following classification (Johnston, 1965):
subclass ACARI
order PARASITIFORMES
suborder Holothyrina
Mesostigmata
Ixodides
order OPILIOACARIFOHMES
suborder Opilioacarina (or Notostigmata) 8
order ACARIFORMES
suborder Tetrapodili
Eleutherengona
Tarsonemini
Labidostommei
Parasitengona
Endeostigmata
Palaeacari
Oribatei
Acaridei
The supra-generic classification of the Acaridei is quite un settled, Many classifications have been proposed. The older schemes, such as those of G. Canestrini, Berlese, Michael, and Trouessart, are now entirely of historical interest. The modern period of acaridid classification may be said to have begun with the system proposed by
Oudemans (1923)* Subsequent to this work, classifications worthy of notice have been published by Vitzthum (19UO-19U3), Baker and Wharton
(1952), Dubinin (1951;), Yunker (1955), and A. M. Hughes (1961).
In the classification adopted in the present study (see MATERIALS),
U8 families are recognized. No estimate of the total number of named species of Acaridei is available. In 1931, Vitzthum listed 37 families containing 871 species; of these 570 were feather mites. Since 1931
the number of described species of Acaridei has surely doubled. HISTORICAL ASPECTS
Because this is not an historical treatise no attempt is made here to follow the vicissitudes of terms and concepts throughout the past studies of the feeding organs of Acaridei. Indeed, relatively little has been done on this subject and much of what has been pub lished could be safely ignored by the mo d e m student of Acaridei.
The last fifty years of the nineteenth century were the heyday of anatomical endeavors in the Acari. It was duringthis period that the great monographs on the anatomy and biology of the mange and sca bies producing mites (Fsoroptidae and Sarcoptidae) appeared. Host of these can now be regarded as part of the lore of medical-veterinary acarology but the works of certain authors such as Robin (e.g., i860) and Megnin (e.g., 1877) are too magnificently done not to be mentioned.
At the end of the century the great Italian acarologist and ento mologist Berlese issued the introductory volume on Acaridei (1897, after the descriptive fasicles had been published) in his classic monograph, Acari, Hyriapoda et Scorpiones Italia. This introductory volume presented labeled figures of the mouth-parts of representatives of many of the then known families (including a figure of a longitudi nal section of the gnathosoma of Tyroglyphus mycophagus, i.e. Calo- glyphus berlesei) and a glossary of terms.
9 10
Shortly after the publication of Berlese’s work, the first volume
(1901) of Michael’s British Tyroglyphidae appeared. That author con sidered the mouth-parts of the free-living Acaridei in some detail but the treatment has many omissions and errors and is not at all up to the usual standard of Michael’s work. The present value of British Tyro glyphidae is in the accounts of the general biology of free-living acaridids and the detailed historical treatment of the taxonomy and anatomy of these mites,
A general (and, unfortunately, unillustrated) summary of the mouth-parts of Acaridei is given by Vitzthum (19U0-19U3) in his mag nificent volume on Acari in "Bronn’s Tierreichs."
The accomplished Russian worker Zakhvatkin (19U1) presented a general description of the exoskeletal elements of the mouth-parts of
Acaridae in his monograph of Palaearctic acaroids. A more detailed treatment is given in his summary of acaroid mites (1953)* In that work he suggested the homology of several gnathosomal setae and pointed out the false segmentation of the palp, Zakhvatkin1s figures are generally accurate and his later paper may be regarded as the starting point of the modern period of study of the mouth-parts in
Acaridei, The concepts developed by Zakhvatkin were followed by
Dubinin (1951) in his introductory volume on the anatomy and biology of feather mites, Dubinin’s presentation is of especial interest be cause he dealt with the musculature of the gnathosoma, in addition to the exoskeletal components. 11
The work of T. E. Hughes Is important because he has attempted to apply the anatomical concepts of Snodgrass (19U8) to the mouth-parts of Acaridei. In 1953 Hughes described the "functional morphology" of the mouth-parts of Anoetus saproayzarum Dufour (i.e., Histiostoma sapromyzarum) and compared them with those of Tyroglyphus farinae
Degeer (i.e., Acarus siro Linnaeus). In 195k he gave a brief (and misleading) description of the gnathosoma of Listrophorus leuckarti
Pagenstecher. In 1959 these accounts were combined into a general description of the mouth-parts of acaridid mites.
In 1959 Knulle published what is by far the most important treat ment of the mouth-parts of acarid mites. His description and figures are largely based on Acarus siro Linnaeus and Glycyphagus destructor
(Schrank) and are restricted to the exoskeletal components. The value of Knulle*a work lies not only in the careful descriptive account but also in his interpretation of the gnathosomal structure in terms of that of related groups such as the Oribatei.
The various works of the authors cited above are the most signifi cant of those dealing with the mouth-parts of the homeomorphic stases of acaridid mites. As a guide to these treatments there is given in
Table 1 a synonymy of certain terms pertaining to the gnathosoma of acaridid mites. The transliteration of the Russian terms (Dubinin and Zakhvatkin) is according to Ericson's (1961) modification of the
Library of Congress system of Russian transliteration. Table 1, Synonymy of some terms pertaining to the gnathosoma of Acaridei.
Present Berlese Michael Vitzthum Dubinin (1951) T. E. Hughes Knulle Usage (1897) (1901) (1&0-19U3) Zakhvatkin (1953) (1953) (1959) chelieera mandibula mandible Chelicere khelitsera chelicera Chelicere coxisternum mentum maxillary Maxillicoxae gnatokoksa Coxistemum lip gnathosoma rostrum trophi Gnathosoma gnatosoma gnathosoma Gnathosoma labrum epipharinx epipharynx epifarinks labrum Oberlippe lateral lips lingua Hypopharynx gipofarinks hypostome Laterallippen palp palpus maxillary Palpus shchupal,tse palp Pedipalpus palp postlabrum subcheliceral shelf pseudorutella maxillae maxillae Maxillen maksilly pedipalpal endites pseudorutellar koksal*nye lopasti process pedipal’p subcapitulum Subcapitulum 13
The mouth-parts of the heteromorphic deutonymphs have largely been ignored or characterized in various non-informative ways. The only significant statements concerning the gnathosoma of hypopi are those of Oudemans (1917) whose interpretation is virtually the same as that given in the present work.
The salivary gland system and the post-pharyngeal alimentary canal of Acaridei are not considered in the present work. For information on the anatomy of the alimentary system, the reader is referred to the accounts of LSnnfors (1930), Vitzthum (19U0-19U3), and T. E. Hughes
(1959)* The same authors, as well as Grandjean (1937), also deal with the salivary glands of these mites. The hypotrophy of the alimentary system of the deutonymphs of Acaridae has been described by Obussier
(1939). MATERIALS, METHODS, AND TERMINOLOGY
MATERIAIS. For this study it has been possible to assemble what is probably the most varied collection of Acaridei ever seen by a sin gle individual; representatives of hS of the 1*8 families recognized were examined. Many of these species were in the collection of the
Institute of Acarology, Ohio Agricultural Experiment Station, Wooster,
A large and significant part of the material, however, was studied at
(and in some cases, borrowed from) various other major acarological collections: British Museum (Nat, Hist,), London; Rijksmuseum van
Natuurlijke Historic, Leiden (Oudemans collection); Institut de Mede- cine Tropicale, Antwerp (Fain collection); Laboratoire d*Acarologie,
Paris (Trovessart collection); and Stazione di Entomologia Agraria,
Florence (Berlese collection),
A list of the determined species seen is given below. The famil ial classification used is essentially that given in Johnston (1965),
As indicated in the Introduction there is, at present, no satisfactory
supra-familial grouping of Acaridei, In the following list the fami
lies have been arranged in five major groups. These are: (1) acaroid group (17 families); (2) associates of birds (17 families); (3) asso
ciates of mammals (12 families); (U) hemisarcoptoid group (1 family);
and (5 ) anoetoid group (1 family),
Family-groups of which no representatives were seen are indicated with an asterisk.
1 k 15
ACAROID GROUP
ACARIDAE Latreille, 1806 (including Caloglyphidae Oudemans, 1932; Ebertiidae Oudemans, 1927; Forcelliniidae Oudemans, 1927; Rhizoglyphidae Oudemans, 1923; Tyro- glyphidae Donnadieu, 1868; Tyrophagidae Oudemans, 192U; and Winter- schmidtiidae Oudemans, 1923)
Acarua farris (Oudemans, 1905) siro Linne, 1758
Acotyledon sokolovi Zakhvatkin, 1941
Aleuroglyphus ovatus (Troupeau, 1878)
Caloglyphus anomalus Nesbitt, 1944 berlesei (Michael, 1903) julidicolus Lawrence, 1939 moniezi Zakhvatkin, 1937 spinitarsus (Hermann, 180U) sp. (OHIO)
Cosmoglyphus krameri (Berlese, 1881)
Histlogaster carpio Kramer, 1882
Lackerbaueria krombeini Baker, 1962
Monieziella corticalis (Michael, 188$)
Mycetoglyphus fungivora Oudemans, 1932
Rhizoglyphus callae Oudemans, 1924 e chinopus (Fumouze and Robin, 1868)
Schwiebla pachyderma Zakhvatkin, 1941 sp. (CONNECTICUT)
Suidasia medanensis Oudemans, 1924 nesbitti Hughes, 1948
Thyreophagus entomophagus (Laboulbene, 1852)
Tyrophagus longior (Gervais, 1814;) mlxtus Volgin, 1949 putrescentiae (Schrank, 1781) similis Volgin, 1949 16
CANESTRINIIDAE Berlese, 1881| Canestrinia dorcicola Berlese, 1881 macgillavryi Oudemans, 1923
Coleopterophagus megninl (Berlese, 1881) procerus Berlese, 1910
Percanestrinia blaptis (Canestrini and Berlese, 1880) sardica Vitzthum, 192lj.
CARPOGLYPHIDAE Oudemans, 1923 Algophagus n, sp, (NEW YORK)
Carpoglyphus lactis (Linne, 1758) munroi Hughes, 1952
Fusohericia incredibilis Vitzthum, 1931
Hericla fermentationis Vitzthum, 1931 hericia (Robin, 1868)
n. gen. "H“, n. sp. (NEW YORK, KANSAS)
CHAETODACTYLEBAE Zakhvatkin, 19Ul ( ■ Trichodactylidae Donnadieu, 1875) Chae todao tylus ludwigi (Trouessart, 1897) osmiae (Dufour, 1839)
CHORTOGLYPHXDAE Berlese, 1897 Chortoglyph.ua arcuatus (Troupeau, 1879)
ENSLINIELLIDAE Vitzthum, 192k Kennethiella trisetosa (Cooreman, 19U2)
Monobiacarus quadridens Baker and Cunliffe, I960
Vespacarus anacardivorus Baker and Cunliffe, I960 folvipes Baker and Cunliffe, I960 histrio Baker and Cunliffe, I960 pedestris Baker and Cunliffe, I960 rufovestis Baker and Cunliffe, i960 saecularis Baker and Cunliffe, i960 tigris Baker and Cunliffe, i960 17
EWINGIIDA2 Pearse, 1929
Ewingia cenobitae Pearse, 1929
N. FAM*, based on Fusacarus Michael
Fusacarus lamlnlpes Michael, 1903 n. sp. (OHIO)
GLYCYPHAGIHAE Berlese, 1887 (including Aeroglyphinae Zakhvatkin, 19^1 and Ctenoglyphinae Zakhvatkin, 19U1) Aeroglyphus peregrinans (Berlese, 1892) robustus (Banks, 1906)
Blomia freeman! A* M* Hughes, 19U8
Ctenoglyphus plumiger (Koch, 1835)
Glycyphagus destructor (Schrank, 1781) domeaticus (Degeer, 1778) geniculatus Vitzthum, 1919 ornatus Kramer, 1881
HYABESIIDAE Halbert, 1915 ( 9 Lentungulidae Oudemans, 1923)
Hyadesia chelopus Andre, 1931 glynni Munson, 1963
LABIDOPHOBIDAE Zakhvatkin, 19Ul
Goheria fusca (Oudemans, 1902)
Labidophorus sciurinus (C* L. Koch, 181|2) soricis Oudemans, 1915 talpae Kramer, 1877 sp* (ex Apodemus; KOREA)
Myacarus arvicolae (Dujardin, 18U9)
Oryctercocenus dispar (Michael, 1886)
Xenoryctes krameri (Michael, 1901) 18
LARDOGLIPHEDAE Oudemans, 1927
Lardoglyphus konoi (Sasa and Asanuraa, 1951) zacherl Oudemans, 1927
UNOBIIDAE Oudemans, 190U
Linobia coccinellae (Scopoli, 1763)
PIROGLTPHIDAE Cunliffe, 1958 (including Dermatophagoidinae Fain, 1963 and Mealiidae Oudemans, 1923)
Dermatophagoides farinae Hughes, 1961 passericola Fain, 196U
Pyroglyphus africanus (a . M. Hughes, 1918) morlani Cunliffe, 1958
ROSENSTEINIIDAE Cooreman, 195U (including Nyc teriglyphinae Fain, 1963)
Mydopholeus capillus McDaniel and Baker, 1962
Nycteriglyphus bifolium Strandtmann, 1962
Rosensteinia sieversl Oudemans, 1923
SAPROGLIPHIDAE Oudemans, 192k (including Calvoliinae Turk and Turk, 1957; Czenspinskiidae Oudemans, 1927; and Oulenziidae Oudemans, 1928)
Calvolia chilensis Gonzalez, 1961 transvers os triata (Oudemans, 1931)
N. FAM., based on Scatoglyphus Berlese
Scatoglyphus n. sp. (OHIO) 19 ASSOCIATES OF BIRDS
ALLOPTIDAE Gaud, 1957 (including Trouessartinae Gaud, 1957)
Laminalloptes longipes (Ewing, 1911) phaethontia (Fabricius, 1775)
Troueasartia appendiculata (Berlese, 188U) minutipes (Berlese, 188U) rosteri (Berlese, 1883)
n. gen. "TM, n. sp. (ex Progne subis; OHIO)
ANALGESIDAE Hegnin, 1880 (including Protalgini Dubinin, 1953; Psoroptoidinae Gaud and Mouchet, 1959; Tillacarinae Gaud and Mouchet, 1959; and Xolalgini Dubinin, 1953)
Analges chelopus (Hermann, l6oU)
Analgopsis corvinus (Megnin, 1877) mucronatus (Buchholz, 1869) pachycnemis (Giebel, 1871) passerinus (Linnaeus, 1758) tridentulatus (Haller, 1882)
Anhemialges albidus (Tyrrell, 1882)
Leptosphyra velata (Megnin, 1877)
Megninia columbae (Buchholz, 1869) ginglymura (Megnin, 1877)
Megniniella gallinulae (Buchholz, 186 9 )
Mesalges Johnstoni Spoiy, 1965 picimajoris (Buchholz, 1869) picipubescentis (Packard, 1868)
Pandalura strigisoti (Buchholz, I8 6 9 )
Protalges accipitrinus Trouessart, 1885
Psoroptoides psoroptopus (Trouessart, 1885) 20
CXTODITIDAE Oudemans, 1908
Cytodites nudus (Vizioli, 1870 psittaci Pain, I960
Cytonyssus andrei Fain, i960
DEBMOGLYPHIDAE Megnin and Trouessart, 1893
Dermoglyphus elongatus (Megnin, 1877)
Sphaerogastra crena McDaniel, 1963
n. gen, "Fn, n, sp, (ex Zenaidura macroura; TEXAS) "Laminosioptes11 hymenopterus Jones and Gaud, 1962 (new genus ,rF")
EPIDERMOPTIDAE Trouessart, 1892
Epidermoptes bilobatus Rivolta, 1876 odontophori Fain and Evans, 196U
Rivoltasia dermicola (Trouessart, 1886)
Strelkoviacarus critesi Spory, 1965
EVANSACABIBAE Fain, 1962*
FALCUUFERIUAE Oudemans, 1905 (* Hypoderidae Murray, 1877 and Falculigeridae Oudemans, 190b)
Bdellorhynchus polymorphus Trouessart, 1885
Cheiloceras taurus Trouessart, 1898
Falcui -i fer rostratus (Buchholz, 1869) n, sp, (ex Columba palumbua; BELGIUM) n, sp, (ex Zenaidura macroura; TEXAS) 21
FREXANIDAE Dubinin, 19U7 (including Kramerellinae Gaud and Mouchet, I96I and Michaelinae Gaud and Mouchet, 1959)
Freyana largifolia Megnin and Trouessart, 188U
Freyanopterolichus pelargicus (Megnin and Trouessart, 188U)
Kramerella lunulata (Haller, 1878)
Michaelichas heteropus (Michael, 1881)
Sulanyssus caputmedusae (Trouessart, 1886) oluschae Dubinin, 1953
KNEMIDOCOPTIDAE Dubinin, 1953
Knemidocoptes mutans (Robin, i860) pilae Lavoipierre and Griffiths, 1951 n. sp. (ex Agelaius phoeniceus; OHIO)
LAMINOSIOPTIDAE Vitzthum, 1931 ( ■ Laminocoptinae Oudemans, 190U)
Laminosioptes cysticola (Vizioli, 1870)
MIIALGESIDAE Trouessart, 1907 (including Heteropsoridae Oudemans, 190U)
Microllchus avus (Trouessart, 1887)
Myialges anchora Sergent and Trouessart, 1907
Myialgopsis trinotoni Cooreman, 19iik
Pronyialges uncus (Vitzthum, 193U)
PRQCTOPHXLLODIDAE Megnin and Trouessart, 1883
Monojoubertia microphylla (Robin, 1877)
Montsauria cylindrlcus (Robin, 1868) 22
PROCTOPHILLODIBAE (Continued)
Proctophyllodes egglestoni Spory, 1965 glandarinus (Koch, 18U0) quadrisetosus Atyeo and Braasch, 1965 truncatus Robin, 1877
Pterodectes rutills Robin, 1868
PTEROUCHIDAE Megnin and Trouessart, 1883 (including Avenzoariidae Oudemans, 1908; Eustathiidae Oudemans, 1908; Grallobiini Dubinin, 1953; Pseudalloptini Dubinin, 1953; Thoracosa- thesinae Gaud and Till, 1961; and Vexillariinae Gaud and Till, 1961) Ardeacarus ardeae (Canestrini, 1878) n. sp. (ex Ardea herodias; OHIO)
Ardeialges n. sp. (ex Ardea herodias; OHIO)
Avenzoaria totani (Canestrini, 1878)
Bychovskiata charadrii (Canestrini, 1878) subcharadrii Dubinin, 1951 n. sp. (ex Charadrius vociferus; OHIO)
Chauliacia tricapitosetosa McDaniel, 1962
Coraciacarus cuculi (Megnin and Trouessart, 188U)
Gabucinia delibata (Robin, 1877) sp. (ex kestrel; EGYPT)
Grallobia fnHcaa (Trouessart, 1885)
Grallolichus minutus Gaud and Mouchet, 1963
Montehadskiana pluvialisi Dubinin, 1951 vanelll (Canestrini, 1878)
Pterolichus obtusus Robin, 1877
Pterygocrusolichu3 chanayi (Trouessart, 1885)
Sokoloviana gracilis (Megnin and Trouessart, 1881;) rehburgi (Canestrini and Berlese, 1880)
Struthiopterolichus bicaudatus (Gervais, I8I4I4.) nouveli ([Andre, i960) 23
PTERONXSSIDAE Dubinin, 1953
Pteronyssoides obscurus (Berlese, 1881*) parinus (Koch, 181*0) striatus (Robin, 1877) truncatus (Trouessart, 1885) tyrrelli (Canestrini, 1899)
Pteronyssus gracilis (Nitzsch, 1818) speciosus Tyrrell, 1882
"Pteronyssus" centurus McDaniel and Price, 1963 simplex Haller, 1882
SIRINGOBIIDAE Trouessart, 1896
"Dermoglyphusn minor (NSrner, 1882)
Syringobia chelopus Trouessart and Neumann, 1888 n. sp. (ex Totanus flavipes; OHIO)
Thecarthra chelopus (Oudemans, 190b)
TURBINOPTIDAE Fain, 1957
Colinoptes cubanensis Fain, I960
Congocoptes furroani Fain, 1956 phoeniculi Fain, 1956 sorenaoni (Tibbetts, 1955)
Mycteroptes basilewskyi Fain, 1956
Pas serrhinoptes andropadi Fain, 1956
Rharaphocoptes capitonidis Fain, 1956
Rhinoptes pternistis Fain, 1956
Schoutedenocoptes aquilae Fain, 1956 dartevellei Fain, 1956 numidae Fain, 1956
Turbinoptes congolensis Fain, 1958 strandtmanni Boyd, 191*8 2U
UNPLACED FEATHER MITES
Bonnetella fuscus (Nitzsch, 1818)
Brephosceles microphaeton (Trouessart, 1885) minutus (Trouessart, 1899)
Zakhvatkinia hydrobatidii Dubinin, 19k9
ASSOCIATES OF MAMMALS
AUDYCOPTIDAE Lavoipierre, 196H*
GALAGALGIDAE Fain, 1963*
GASTRONYSSIDAE Fain, 1956 (including Rodhainyssinae Fain, 1961i)
Gastronyssus bakeri Fain, 1955
Opsonyssus asiaticus Fain, 1959 brutsaerti (Fain, 1956) eidoloni Fain, 1959 indiea Fain, 1959 phyllorhinae Fain, 1959 zumpti Fain, 1959
Rodhalnyssus yunkeri Fain, 1956
LEMURNISSIDAE Fain, 1957
Lemurnyssus galagoensis Fain, 1957
Mortelmansia brevis Fain, 1959 longus Fain, 1959 25
LESTROPHORIDAE Canestrini, 1892 (including Atopomelinae Gunther. 19U2; Chirodiscinae Trouessart, 1892; and Labidocarpinae Gunther, 19u2)
Austrochirus perkinsi Domrow, 1958
Chirodiscoides caviae Hirst, 1917
Cytostethum mollisoni Domrow, 1961
Histiophorus mingaudi (Trouessart, 1896)
Labidocarpus rolllnati Trouessart, 1895
Listrophoroides aethiopicus Hirst, 1923 expansus Ferris, 1932
Listrophorus amerioanus Radford, 19UU bakeri Radford, 19U8 dipodomius Radford, 1953 dozieri Radford, 19Ui- gibbus Pagenstecher, 1861
Parakosa tadarida McDaniel and Lawrence, 1962
Tenrecobia pauli.ana Lawrence, 195U
MIOCOPTIBAE Gunther, 19l2 Criniscansor criceti Poppe, 1887
Myocoptes janesoni Radford, 1955 musculinus (C. L. Koch, 1838)
PNEUMOCOPTIDAE Fain, 1957
Pneumocoptes jellisoni Baker, 1951 penrosei (Wiedman, 1917)
PSOROPTIDAE - complex Gebalginae Fain, 1962 Fonsecalges saimirii Fain, 1963
Cheirogalalginae Fain, 1963* PSOROPTIDAE - complex (Continued)
Chorioptinae Sweatman, 1958
Caparinia tripilis (Michael, 1889)
Chorioptes bovis (Hering, 18U5) texanus Hirst, 192U
Otodectes cynotis (Hering, 1838)
Makialgesinae Gaud and Mouchet, 1959*
Marsupialginae Fain, 1963*
Paracoroptinae Fain, 1963*
Psoralginae Oudemans, 190J4 (including Acaroptidae Womersley, 1953) Psoralges andrei Fain and Johnston, I96J4. ~ jj^bertus Trouessart, 1896
Psoroptinae Canestrini, 1892 Psoroptes cervinus Ward, 1915 cuniculi (Delafond, 1859) natalensis Hirst, 1919 ovis (Hering, 1838)
RHXNCHOPTIDAE Lawrence, 1956 Rhynchoptes anastosi (Fain, 1962)
SARCOPTIDAE Sundvall, 1833 ( = Acaridae Oudemans, 190b) Baker acarus corynorhini Fain, 1961 schoutedeni (Fain, 1959)
Chlrnyssoldes brasiliensis Fain, 1959 caparti Fain, 1959 Chimyssus myotic ola Fain, 1959
Notoedres benoiti Fain, 1959 cuniculi (Gerlach, 1857) douglasi Lavoipierre, I96U tadaridae Fain, 1959 27
SARCQPTIDAE (Continued)
Mycteridocoptes lavoipierrei Fain, 1958 macrophallus Fain, 1958 microphallus Fain, 1959 minlopteri Fain, 1959 poppei Oudemans, 1898 rousetti Fain, 1958
Sarcoptes caprae Furstenberg, 1861 suis Gerlach, 1857 vulpis Furstenberg, l86l
TEINOCOPTIDAE Fain, 1959 (including Bakerocoptinae Fain, 1962)
Bakerocoptes cynopteri Fain, 1962
Chirobia congolensis Fain, 1959
Teinocoptes asiaticus Fain and Domrow, 1961 astridae Fain, 1959 auricularis Fain, 1959 domrowi Fain, I960 epomophori Rodhain, 1923 rousetti Fain, 1959
YUNKERA.CARIDAE Fain, 196U lunkeracarus faini Hyland, and Clark, 1959 muris Fain, 1957
HEMISARCOPTOID GROUP
HEMISARCOPTIDAE Oudemans, 190U
Hemisarcoptes malus (Shimer, 1868) 28
ANQETOID GROUP
ANGETIDAE Oudemans, I90U (including Histiostomatina Berlese, 1897 (nomen oblitum), Hjdanoetini Scheucher, 1957, Nodipalpidae Oudemans, 1923, and Spinanoetini Scheucher, 1957)
Anoetus hughesi Hunter and Hunter, 1?6U
Bonomia sphaerocerae Vitzthum, 1922
Creutzeria tobaica Oudemans, 1932
Histiostoma feroniarum (Dufour, 1839) himalayae (Vitzthum, 1923) polypori (Oudemans, 19lU)
Myianoetus muscarum (Linne, 1758)
Pelzneria crenulata (Oudemans, 1909)
Prowichmannia spinifera (Michael, 1901)
Rhopalanoetus lanceocrinus (Oudemans, 191U)
Spinanoetus pelznerae Scheucher, 1957
The following groups are inadequately characterized and of uncertain status: Myrmolichinae TtJlrk and Tflrk, 1957; Nanacaridae
Oudemans, 1923; Olafseniidae Oudemans, 1927; and Pontoppidaniinae
Oudemans, 192$, Of these only Manacarus minutus (Oudemans, 1902)
(Nanacaridae) has been seen but the material is too poor to permit
detailed study. 29
Although a large variety and. number of specimens were available for this study, it must be emphasized that not all of this material was suitable for detailed examination of the mouth-parts* The majority of the specimens studied at or obtained from other collections were pre served as 8lide-mounts. Because so many of these were type, uniques, or otherwise of special value, it was not possible to dissect or re mount the specimens. This, of course, limited the sorts of observa tions that could be made.
METHODS. Material for routine study was preserved in 70-85# ethyl alcohol. For preliminary examinations, specimens were mounted in lactic acid in cavity (hanging drop) slides (method of Grandjean,
19li9). Such preparations permitted observation of the gnathosomal- idiosomal relationships and the general facies of the gnathosoma.
For measurements, specimens were mounted in lactic acid on ordinary slides with supports under the cover glass. For critical study and drawing of exoskeletal features, entire specimens, gnathosomae, or gnathosomal components were prepared as temporary mounts in lactic acid or Berlese*s fluid. The small size of most of the species studied precluded any orderly process of dissection. For such spe cies preparations of gnathosomal components were made as follows:
(1) alcoholic specimens were cleared in lactic acid; (2) the gnatho soma was separated from the idiosoma and mounted; (3) while the speci men was under observation with a compound microscope, gentle pressure was applied to the cover slip, thus separating the chelicerae and causing them to lie on their lateral surfaces. The removal of the chelicerae permitted observation of the subcapitulum and palps. When properly executed this method resulted in virtually no distortion of
the gnathosomal components. Distortion artifacts, when they occurred, were usually a result of the clearing process rather than the mounting
procedure. Clearing agents, particularly lactic acid, cause separation
of cuticular layers and swelling of the outer layers in unsclerotized
areas such as synarthrodial membranes. Although such swellings are
clearly artifacts, they are minor ones and pose no problem in inter
pretation. A more important possible source of error is the inter
pretation of other semi-membranous structures such as the cheliceral
apophyses, pseudoruteliar processes, and the labrum. These structures
are shrunken in alcoholic specimens and swollen in cleared specimens.
Which of these conditions more nearly approximates the state in the
living mite is not known but the problem can be defined away by re
stricting statements to those based on observation of specimens
treated in a more or less uniform maimer (in this case, cleared
specimens)•
The majority of prepared specimens from collections other than
that of the Institute of Acarology were mounted in Berlese*s fluid.
Mott of these were studied in their original condition.
For examination of the intrinsic and extrinsic musculature of
the gnathosomal components, specimens were fixed in Bouin’s fluid,
dehydrated, cleared in carbo-xylene, and mounted in daaiar. The best
preparations of this sort were obtained when the opisthosoma of the
specimen was punctured to facilitate passage of the various reagents.
Two species, Caloglyphus berleaei (Michael) and Tyrophagus
putrescentiae (Schrank), were studied by means of serial sections. 31
The sections were prepared by standard methods; staining was with
Mallory triple stain.
Observations were made with ordinary light and phase-contrast microscopy. Drawings were prepared with the aid of an ocular grid and ruled paper.
TERMINOLOGY. No aspect of morphological endeavor is as likely
to result in controversy as is "terminology11 and, yet, no polemics
are as sterile as those stemming from controversy over names. Al
though the student of comparative anatomy can refuse to be drawn into nomenclatural squabbles, aloofness from sterile argument should not be regarded as license for the pursuit of a highly personal and idio
syncratic terminology. Morphological terminology in the Acari is in
a rather confused state and in this study it has been necessary to choose from a variety of previously used terms. In the selection of
terms three criteria were applied: (1) usage; (2) priority; and
(3) etymological appropriateness; in that order. Application of
the first two criteria was based on a study of the literature per
taining to the morphology of the mouth-parts of all mites rather than
that of the Acaridei alone.
A synonymy of some terms applied by previous workers to the mouth-
parts of acaridid mites is given in Table 1. A glossary of terms is
given in Appendix II. THE MOUTH-PARTS OF CALOGLIPHUS BERLESEI (OUDEMANS) (ACARIDAE)
Caloglyphus berlesei is a large, common, widely distributed (? cos mopolitan) member of the acarid subfamily Rhizoglyphinae. It is a synantropic species and occurs in relatively damp situations such as moldy stored food products, "barnyard” habitats, and poultry litter, where the moisture content is not less than 25%, In Ohio, C. berlesei is common in the deep litter of poultry houses. The general biology of the species has been briefly summarized by Zakhvatkin (19hl). The feeding habits of C. berlesei in nature are not precisely known. In laboratory cultures the species does well on moistened granules of commercial activated yeast, a very soft diet. The occurrence of this mite in damp habitats suggests that its natural food is probably simi lar in physical character to that taken in the laboratory.
The choice of C. berlesei for detailed anatomical study was based on the following considerations: (1) large size; (2) the generalized structure of the gnathosoma (as determined by preliminary studies); and (3) ready availability as a laboratory animal; of which the first was the most important.
The post-embryonic development of C. berlesei includes a larva, a protonymph, a deutonymph, a tritonymph, and an adult. Because the mouth-parts of the heteromorphic deutonymph differ greatly from those of the homeomorphic stases, they will be treated separately.
32 33
THE GNATHOSOMA OP THE HGMEOMORPHIC STASES. The gnathosoma of the adults of Caloglyphus berlesei is an anatomical and functional unit that is articulated with the remainder of the body, the sac-like idio- soma. The gnathosoma is approximately one-fifth the length of the idiosoma and, in life, is carried at an angle of about 30° from the longitudinal axis of the body. The components of the gnathosoma are
(1) a pair of dorsal, chelate appendages, the chelicerae, that articu late with the idiosoma and the remainder of the gnathosoma through a complex synarthrodial membrane; and (2) a ventral, beak-like structure, the subcapitulum, that laterally bears a pair of appendages and, bas- ally, articulates with the idiosoma.
Each chelicera consists of two major sections: the cheliceral sheath and the chelicera proper.
The cheliceral sheath (ch sh) is a complex synarthrodial membrane
(Figures 1, 2, 3). The sheath attaches to the body of the chelicera at the level of the basal fourth; the line of attachment encircles the chelicera (indicated by heavily dotted line in Figure 3)* The sheath extends forward for a short distance (approximately one-fourteenth of the length of the chelicera) and doubles back on itself. Medially the sheaths are continuous with one another; dorsally and laterally they are continuous with the integument of the idiosoma; and ventrally they are continuous with the integument of the dorsal face of the subcapi tulum. The sheaths are thus a complex, flexible outpouching of the integument; the space they enclose is haemocoelic space and the cu- ticular structures they surround are apodemes. The sheaths provide increased mobility to the chelicerae. The nature of the sheaths permit separate movement of each chelicera.
The chelicera proper is elongate; oval in cross-section; highest in the basal third; and tapers anteriad in width and height. The cheli cera comprises three sections: the shaft, the fixed digit, and the movable digit (Figure 2).
The cheliceral shaft is a hollow cylinder; basally it opens to the body cavity. The basal opening, as viewed dorsally, cuts the chelicera obliquely; the opening is entirely paraxial (Figure 2).
The cheliceral shaft is rather heavily sclerotized except for the ventral cuticle just basad of the articulation with the movable digit.
The shaft is smooth and without processes on the antiaxial surface
(Figure 3)* The paraxial surface bears a seta and spurs (Figure 2).
The paraxial cheliceral seta (ch1) is inserted near the base of the fixed digit. Dorsad of the seta is an unidentate cheliceral spur
(ch sp); a bidentate spur is located basad of the seta. On the ven tral surface of the shaft, originating in the area of soft cuticle, are two cheliceral apophyses (Figure 2; ch aps).
The cheliceral shaft is continued distally as a sclerotized fixed digit (Figure 2; f d). The ventral surface of the fixed digit forms the dorsal occluding face of the chela (detail in Figure 7).
Articulating with the cheliceral shaft is the movable digit (Fig ure 2; m d). The base (apodemal) of the movable digit articulates with paired condyles on the walls of the shaft. The dorsal surface of the movable digit forms the ventral occluding face of the chela
(detail in Figure 7). The chelicera of C. berlesel may be designated as chelate-dentate.
The dentition is oligodont and heterodont.
The chelicerae are provided with intrinsic and extrinsic muscula ture* The extrinsic musculature consists of the cheliceral retractors.
These muscles insert on the ventral surface of the cheliceral shaft, just basad of the attachment of the sheaths. The retractors of each chelicera divide into two slips and extend to their origins on the prodorsum at the anterior margin of the dorsosejugal groove. This origin is behind the posterior margin of the prodorsal shield.
The intrinsic musculature of the chelicera comprises a levator muscle and a depressor muscle (Figure U; 1 ptr and d ptr, respectively).
The levator is a massive muscle consisting of numerous slips that join
as a large tendon inserting on the dorsal ridge of the apodemal portion
of the movable digit. The levator has its origins on lateral and dor
sal faces of the cheliceral shaft. The depressor muscle originates on
the antiaxial wall at the base of the shaft. The slips converge as a
long tendon that inserts on the ventral face of the apodemal portion
of the movable digit.
The second major component of the gnathosoma is the subcapitulum.
In C. berlesei, the subcapitulum is (in dorso-ventral aspect) more or
less pyriform in outline. Basally the subcapitulum articulates with
the idiosoma through the narrow circumcapitular furrow; dorsally it
is joined with the cheliceral sheaths. The principal surfaces of the
subcapitulum are the dorsal and ventral faces.
Situated on the dorsal face of the subcapitulum and extending al
most to its anterior margin is a long, hollow, tongue-like structure, 36 the labrum (Figure 5; Ls). The labrum is smooth on the dorsal and ven tral surfaces; along the entire ventro-lateral margin is a fringe of fine setules. At the base of the labrum are two pairs of basally- directed apophyses; the more basad of these articulates with a larger postlabral apophysis (Figure 5; aps). Dorsally the labrum bears a median longitudinal sclerite that presumably acts as a strengthening bar* The dorsal surface of the labrum is continuous with cuticle covering the posterior half of the subcapitulum. Laterally the labrum is continuous with the cuticle of the dorsal surface of the ventral wall of the subcapitulum. The labrum is hollow; its cavity is haemo- coelic. Inserting on the antero-ventral surface of the labrum is a muscle — the labral retractor (Figure 9; lbr rtr). This muscle divides into two slips and passes to its origins on the dorsal wall of the subcapitulum.
Basad of the labrum and forming the dorsal wall of the posterior portion of the subcapitulum is the postlabrum (Figure 5; pstlbr).
Medially the postlabrum is raised as a dorsal ridge; the ridge sepa rates paired depressions. These depressions are the cheliceral fossae, in which the chelicerae rest. On either side of the dorsal ridge are prominent, small muscle scars, the origins of the labral retractor muscle (Figure 12). The cheliceral sheaths attach to the postlabrum; that portion of the postlabrum behind the attactiment of the sheaths is apodemal.
Ventrally the subcapitulum is bounded by well sclerotized cuticle that extends dorso-laterally to continue with the cuticle of the post labrum and that extends anteriad beyond the level of the labrum. That 37 portion of the lateral and ventral wall of the subcapitulum that is basad of the level of the subcapitular appendages is presumed to rep resent the region of the pedipalpal coxae and is designated the coxi- stemum (Figure 6; Cxst). Anteriad the ventral wall of the subcapi- tulum is produced as two large lateral processes and a short, median, unpaired process*
The median, unpaired process is here interpreted as representing the lateral lips (Figures 6, 8; LL). On the dorsal surface of the ven tral subcapitular wall the lateral lips continue basad as a prominent ridge. The ventral face of the lateral lips is without setae.
The paired, lateral projections of the ventral subcapitular wall are the pseudorute11a (Figure 6; psr). Laterally the pseudorutella curve dorsad so that together they form a trough (Figure 10). The dorso-lateral tips of the pseudorutella bear large cuticular teeth.
The dorsal cuticle of the pseudorutella is continuous posteriorly with the base of the labrum and with the postlabrum. At the base of the labrum, where the ventral subcapitular wall and labrum join, is an orifice, here designated mouth*.
The mouth* is the entrance to the alimentary canal. From its ori gin it continues as a cuticular tube through the subcapitulum. This tube is the pharynx (Figures 9, 11; ph). In cross-section (Figure 11), the pharynx is flattened and has the edges curved dorsad; it thus re sembles a closed trough. The pharynx terminates just basad of the sub capitulum where it is confluent with the oesophagus. The junction of the pharynx and oesophagus is the mouth** (Figure 9). 38
The pharynx is a pumping organ. Dilation of the pharyngeal cavity results from the contraction of two sets of muscles, the pharyngeal di lators (Figure 11; dil ph). Inserting on the dorsal wall of the pharynx are five paired groups of dorsal dilators; these muscles originate on the lateral walls of the coxistemum. Inserting on the ventral faces of the lateral margins of the pharynx are three paired groups of ventral dilators; these originate on the postero-ventral coxistemal wall.
Originating (and inserting) on the dorso-lateral edges of the pos terior half of the pharynx are three band-like muscles — the pharyngeal constrictors (Figure 11; cons ph). The contraction of these muscles pulls the lateral edges of the pharynx toward the median line. This forces the dorsal wall of the pharynx down and against the ventral wall, thus closing the pharynx.
The pharyngeal dilators and pharyngeal constrictors are antago nistic muscles. Their alternate, serial, contractions result in the pumping action of the pharynx. Opening and closing of the anterior orifice of the pharynx is a function of the labrum and is accomplished by relaxation and contraction of the labral contractor*
The ventral surface of the pharynx is provided with a complex sclerotic formation, the subpharyngeal sclerite (Figure 6; subph).
This sclerite joins medio-distally with the wall of the coxistemum.
On the dorso-lateral surfaces of the subcapitulum are located the paired supracoxal setae (Figure 5; elc p). These setae originate mid way between the posterior margin of the subcapitulum and reach to the level of the synarthrodial membrane at the base of the palp. In this species, the supracoxal setae are stout and lightly barbed. 39
On the ventral surface and originating at the level of the middle of the subcapitulum are subcapitular setae (Figure 6; a)* These are long and thin and extend just beyond the anterior margin of the subcapitulum.
Arising from the lateral surfaces of the subcapitulum are the paired pedipalpal telopodites, or palps (Figures 6, 13; Pp). The palps are filiform, oval in cross-section, and consist of two podomeres. The podomeres are delimited by sclerotization of the palp cuticle; they are separated by an irregular annulus of unsclerotized cuticle. The basal podomere, which is somewhat longer than the distal one, is straight and lies adpressed to the lateral subcapitular wall. The distal podomere is turned ventra-medially from the main axis of the palp and lies obliquely across the antero-antiaxial comers of the subcapitulum.
On the dorsal surface of the basal podomere, just basad of its distal margin, is a slit-like structure, the lyrifissure (Figure 13; lyr). Also borne on the basal half of this podomere are two setae.
One of these arises from the dorso-lateral surface (Figure 13; dg) and the other is ventral (Figure 13; v).
Inserted in the synarthrodial membrane separating the palpal podomeres is the long, distal dorsal seta (Figure 13; d]_). At the base of the seta is a small, hyaline process.
The distal podomere of the palp is shaped very differently from the basal one. The dorsal cuticle projects in the form of a hood over the tip of the palp. Arising just beneath the hood is a short, rod-like, hollow seta, the sole nidi on omega (Figure 13). Ventral to the solenidion is a larger, cylindrical, hollow process that projects Uo slightly downward from the palp. This structure is of unknown homology and is here called simply the disti-ventral organ (Figure 13j x).
The musculature of the palp consists of a single extrinsic mus cle— the palpal adductor (Figure II45 add pp). This muscle is a wide, thin band that originates on the postero-lateral corner of the sub capitulum and inserts on the basa-paraxial margin of the palp. Its action is (apparently) to adduct the palp.
The above description of the mouth-parts of the adults is appli cable in entirety to those of the homeomorphic immature stases. The mouth-parts of these stases differ from those of the adults only in size.
THE GNATHOSOMA OF THE HETEROMORPHIC DEUTONYMPH. The gnathosoma of Caloglyphus is particularly well suited for anatomical analysis as it is present in a relatively unmodified condition in this genus.
The gnathosoma of C. berlesei is situated on the ventral surface of the propodosoraa at the level of trochanter I. It is articulated in a semi-circular basal ring of sclerotized cuticle that extends ven- trally and laterally about the base. The gnathosoma is composed of two principal anatomical regions: a cylindrical basal unit and a pair of appendages borne on the distal end of the unit. In ten specimens measured the length of the gnathosoma ranged from 27-3h microns and the ratio length of idiosoma/length of gnathosoma was 9.2-10.7#
On the basis of form and position the basal unit of the gnatho soma is interpreted as representing the subcapitulum (Figures 15, 16;
(Subc). The subcapitulum is a hollow cylinder with a distal, ventral, median cleft and a pair of basal apoderaes (Figure 16). At the level Ui of the middle of the subcapitulum, on the dorsal-laberal surfaces, is a pair of setae, interpreted as the homologues of the supracoxal setae
(elc p)* In C. berlesei the supracoxal setae are spatulate basally and highly attenuated distallyj the length is greater than that of the gnathosomal appendages. On the ventral surface of the subcapitulum, on either side of the median cleft, is a pair of clear areas in the cuticle; these are probably vestiges of the subcapitular setae (Fig ure 1 6 ).
Originating on the distal face of the subcapitulum are the paired appendages here interpreted as the palps. The palps are shorter than the subcapitulum; cylindrical; distally truncated; well sclerotized; bear distally a short, acute, hyaline process; and are fused basally.
On the dorsal surface of the palp is a prominent lyrifissure (Fig ure 1J>; lyr). Basad of the lyrifissure is a seta, here interpreted as the homology of &2 (Figure 15). Arising from the distal face of the palp is a large solenidion (Figure l£; omega) that is considered to be the homolog of the solenidion of the palp of the homeomorphic stases. In contrast to the short, rod-like solenidion of the other stases, however, that of the deutonymph is slender, tapering, and elongate (similar in form to the tibial solenidia of the legs of the homeomorphic stases).
The following structures are absent or not recognizable as such in the gnathosoma of the deutonymph of C. berlesei; chelicerae, labrum, postlabrum, mouth (or any oral opening), pharynx, and the palpal setae d^ and v. COMPARATIVE STUDIES
THE RELATION OF THE GNATHOSOMA AND IDIOSQMA. In the majority of acaridid mites the gnathosoma is articulated anteriorly on the idiosoma
(Figures 1, 17, 18), The longitudinal axis is the same as the axis of the idiosoma or projects ventrally at an angle of less than kS° from that axis.
In Schwiebia (Acaridae) (Figure 19), a genus of litter-dwelling
(fossorial ?) forms, the gnathosoma is carried at an angle of virtually
90° from the longitudinal axis of the idiosoma. The same situation holds for Gastronyssus bakeri Fain (Gastronyssidae), a species living in the gastric mucosa of fruit bats.
In the mites of the families Chortoglyphidae, N, Fam. (Fusacarus), and Labidophoridae, the gnathosomal-idiosomal articulation is antero- ventral. An anterior extension of the prodorsal shield covers the mouth-parts dorsally. In the oribatid mites, this condition is termed stegasimy (e.g., Grand jean, 195H) and the name may also be applied here. Species in which the gnathosoma is visible from above (the ma jority of Acaridei) are termed astegasime,
THE CHELICERAE. The description of the chelicerae of Caloglyphus berlesei will suffice for a general statement of the basic plan of cheliceral morphology in acaridid mites. In this basic type the chelicerae have well-developed sheaths, are chelate-dentate, and
1*2 are provided with paraxial seta and spurs and ventral apophyses. Vari ous modifications of this basic type involve changes in relative dimen sions of the chelicera, changes in the digits and dentition, loss of spurs and setae, and development of new processes. Examples of chelate- dentate chelicerae are shown in Figures 2, 3> 20-26, 28-38, ij.0-U5.
The cheliceral sheaths are almost always present in acaridid mites.
The sheaths are definitely absent in the Cytoditidae and were not seen in the various species of Opsonyssus (Gastronyssidae). The material of the last-mentioned group was not entirely favorable for study, however.
Chelicerae such as those of Glycyphagus destructor (Schrank) (Glycy- phagidae) (Figure 20) and Chortoglyphus arcuatus (Troupeau) (Chorto- glyphidae) (Figure 21) show strong resemblance to those of oribatid mites. The massive form of these chelicerae is probably correlated with feeding on relatively dry, particulate matter. The chelicerae of Caloglyphus are essentially similar (Figures 2, 3) but show a more elongate form. Those of Carpoglyphus lactis (Linnaeus) (Carpoglyph- idae) (Figure 23) are also somewhat elongated and the dentition is weaker. The chelicerae of Ewingia cenobitae Pearse (Ewingiidae) (Fig ure 2U) are even more slender; the digits are slender and the teeth reduced in number.
In members of the genus Dermatophagoides (Pyroglyphidae) (Fig ure 22), the chelicerae are generally similar to those of the Glycy- phagidae. They differ in that the digits are relatively shorter and the dentition is more heterodont. The anterior ventral apophysis is well developed. On the paraxial face there is a hyaline process that partially covers the digits. This is the cheliceral hood (ch hd). hh
The paraxial cheliceral hood is a development unique to Acaridei.
It has been observed in bird- and mammal-infesting ectoparasites of the families Alloptidae, Analgesidae, Epidermoptidae, Freyanidae, Procto- phyllodidae (Figure 3U), Pterolichidae (Figures 31, 32), Pteronyssidae
(Figure 30), Syringobiidae (Figure 29), Myocoptidae (Figure UO), and
Psoroptidae (Cebalginae, Chorioptinae, and Psoralginae) (Figures 33, 38)*
In certain of the mammal-infesting ectoparasitic groups there is present, on the fixed digit, a dorsal hyaline process (hy pr). This is illustrated for Psoralges libertus Trouessart (Psoroptidae-Psoralginae)
(Figure 33), Otodectes cynotis (Hering) (Psoroptidae-Chorioptinae) (Fig ure 38), Listrophorus dozieri Radford (Listrophoridae) (Figure hi), and
Chirodiscoides caviae Hirst (Listrophoridae) (Figure U2). This dorsal hyaline process is absent in the feather mites.
In the families Knemidocoptidae and Sarcoptidae, intra-dermal parasites of birds and mammals, respectively, the chelicerae are rela tively simple. Despite the apparent similarity of their way of life, the chelicerae of these mites differ markedly. In the knemidocoptids
(Figure hk) the chelicera is massive and the digits are short. In sarcoptids (Figure 1*3) the cheliceral shaft is curved and the digits are relatively slender.
The chelicerae in the closely related families Gastronyssidae,
Pneumocoptidae, and Yunkeracaridae have a distinctive form. The cheliceral shaft is short and the digits are long and provided with sharp, distal teeth (Figure U5).
In the Psoroptinae the chelicera (Figure 39) differs markedly from other Psoroptidae. The digits are slender and lack apposing teeth. The fixed digit bears two terminal teeth. The single tooth of the movable digit is retrorse. It is possible that the ventral face of the movable digit is a cutting surface in these mites. The che liceral seta, spurs, hood, and apophyses are absent.
In Hemisarcoptes (Hemisarcoptidae) the chelicera is simple and without processes. The digits are slender and curved dorsad (Fig ure 26),
The chelicera of anoetid mites is distinctive; that shown for
Histiostoma polypori (Oudemans) is representative (Figure 25). The cheliceral shaft is poorly sclerotized and the digits appear mem branous , An elongate dorsal hyaline process is present on the fixed digit. On the paraxial surface there is a well-developed cheliceral hood. The paraxial seta is present and highly elongate.
Complete reduction of the fixed digit is seen in Linobia cocci- nellae (Scopoli) (Linobiidae) (Figure 27), the Lemurnyssidae (Fig ure 58), Cytonyssus (Cytoditidae) (Figure 5U), and the Laminosiopti- dae. The movable digit is in the form of a three-barbed harpoon in the linobiids and lemumyssids; presumably, this represents an anchor ing device. In Cytonyssus and Laminosioptes the shaft of the digit is edentate but the terminus is three-pronged (a rasping device ?).
Associated with reduction of the fixed digit is the loss of setae and spurs and the absence of cheliceral processes in these species.
In Cytodites nudus (Vizioli) (Cytoditidae), the chelicerae are completely absent or at least not recognizable as such. U6
The intrinsic musculature of the chelicerae is apparently identi
cal with that of Caloglyphus berlesei in all species of Acaridei in which a well-developed movable digit occurs. The tendons of the levator and depressor muscles usually persist even in cleared speci mens, thus permitting the recognition of a normal musculature. These
tendons are included in many of the figures of chelicerae given in
this study (e.g., Figure 39).
As was indicated in the Introduction, the feather mites of the family Falculiferidae display inter- and intrasexual polymorphism as regards the form and size of the chelicerae. This polymorphism has been generally known for many years but it was first described in de
tail by Dubinin (19!? 6) in his monograph of the "Falculiferinae." That author gave figures of the chelicerae of the females and polymorphic males of Falculifer rostratus (Buchholz) and Bdellorhynchus polymorphus
Trouessart and diagrammed the idiosoma and chelicerae of various sizes
of polymorphic males of the latter species. Dubinin did not attempt
to characterize the cheliceral-idiosomal relationship of these mites
in a quantitative manner although it seems possible that this relation
ship is one of allometry and therefore of more than casual interest.
To determine the size relations between the idiosoma and the
chelicerae, the lengths of these structures were measured in males
and females of Falcn lifer rostratus and in males of F. n. sp. (ex
Zenaidoura) and Bdellorhynchus polymorphus. The length of the idio
soma (X) was measured on the median line. The length of the movable
digit was used as a measure of cheliceral length (X), U7
The allometric equation is (Simpson, Roe, and Lewontin, I960)
I = b Xa and in log form
log Y = log b + a log X where a is the slope and b is the Y intercept (the value of Y when X is unity). When the value of a is greater than unity the growth pat tern is said to be positively allometric and when a is less than unity the pattern is one of negative allometry. When the value of a is equal, or approximately so, to unity, the relationship between the structures is isometric.
The allometric constants a and b and the correlation coefficient r estimated from these measurements are given in Table 2. As may be seen from this Table the estimates of a for Falculifer n* sp. and F. rostratus are significantly different from 1 at the .01 level (by t- test). Because the values of a are greater than 1 the relation ship of the cheliceral length to the idiosomal length is one of posi tive allometry. Although the estimate of a for Bdellorhynchus poly morphus was 2.69, this value is not significantly different from unity. The test of significance of the a value for the females of
F. rostratus indicated that the idiosomal-cheliceral relationship was also isometric.
The chelicerae of the male of Bdellorhynchus polymorphus, the female of Falculifer rostratus, and the polymorphic male of F. rostratus are shown in Figures 35, 36, and 37, respectively. U8
Table 2. Allometric constants for idiosomal length (X) and cheliceral length in 3 species of Falculiferidae.
Species n a ± S.D. b ± S.D. (log e)
Bdellorhynchus polymorphus 7 2.69 ± 1.53 -10.6 ± 9.33 .617 (males)
Falculifer n. sp. 7 3.U7 1 .5^2*# -15.8 ± 3.35 • 9hh#* (males)
Falculifer rostratus 7 2.6l t .399** -11.6 i 2,$k .9U6#* (males )
Falculifer rostratus 10 .U28 - .222 1.86 t 1.U0 .563 (females)
** significant at .01 level h9
THE SUBCAPITULUM. The description of the subcapitulum of Calo- glyphus berlesei is applicable in detail to members of the families
Acaridae, Canestriniidae, Carpoglyphidae, Chaetodactylidae, Enslini- ellidae, Hyadesiidae, Lardoglyphidae, Saproglyphidae, and N. Fam.
(Scatoglyphus) and in general to most other Acaridei.
The subcapitulum is a hollow semi-cylinder. The dorsal face com prises the labrum and postlabrum. The ventral and lateral faces com prise the coxistemum. Projecting anteriorly from the coxistemum are the paired pseudorutella. Between the pseudorutella is a short, median element, the lateral lips. Each of these components varies within
Acaridei. In addition, new processes may be developed.
The cuticular element within the subcapitulum is the pharynx. The form of the pharynx and the subpharyngeal sclerite vary considerably but these variations are as yet unstudied.
The labrum was not studied in detail in these mites. It is present and well developed in all groups except the Cytoditidae (see below). In free-living groups in which the subcapitulum is relatively short and broad (i.e., the length/width ratio is low), such as the Glycyphagidae,
Labidophoridae, and Pyroglyphidae, the labrum is also short and broad.
The same condition holds for some parasitic groups such as the Turbin- optidae and lunkeracaridae (Figure 53; Ls). In free-living and para sitic forms where the subcapitulum is elongated, the labrum is also elongate and narrow (e.g., some Acaridae, Figure 5; Canestriniidae,
Carpoglyphidae, Ensliniellidae, and Psoroptidae-Psoroptinae, Fig ure 68). 5 0
The pseudorutella are short, relatively narrow, dorsally re curving processes in Caloglyphus (Figures 5, 6). The lateral lips are represented, in ventral aspect, by a short, knob-like, median process*
This arrangement of the pseudorutella and lateral lips is seen in Acar idae, Canestriniidae, Carpoglyphidae, Chaetodactylidae, Ensliniellidae,
Hyadesiidae, Lardoglyphidae, Saproglyphidae, and N* Fam. (Scatoglyphus)*
In the Chortoglyphidae, N. Fam. (Fusacarus), Glycyphagidae, Labi- dophoridae, and Pyroglyphidae, the subcapitulum is relatively broad in ventral aspect and the lateral lips are represented by a well-developed median element. This condition is illustrated for Glycyphagus domesticus
(Glycyphagidae) (Figure U6j psr, LL) and Dermatophagoides passericola
(Pyroglyphidae) (Figure 1*7; psr. LL). The type of subcapitulum exem plified by Dermatophagoides is also found in the Turbinoptidae and, in various other parasitic groups. The form of the pseudorutella in many of the parasitic groups, however, is complicated by the development of new structures, the pseudorutellar processes.
Pseudorutellar processes (psr pr) are flat, hyaline, flap-like projections arising from the anterior or antero-ventral face of the pseudorutella. In their simplest form they are seen as short, ven- trally-directed, hyaline lobes of the pseudorutella (e.g., Analgesidae,
Epidermoptidae, Myialgesidae, Myocoptidae, and Psoroptidae-Chorioptinae and Cebalginae). In the groups cited the pseudorutella are poorly de veloped as are the lateral lips. A more elaborate development of the pseudorutellar processes is seen in various families of feather mites —
Alloptidae, Dermoglyphidae, Falculiferidae, Freyanidae, Pterolichidae,
Pteronyssidae, Syringobiidae — and in the psoroptine Psoroptidae and 51 the Rosensteiniidae. In some feather mites the processes are paired, distally attenuated lobes, which together give the appearance of a hyaline moustache* In the Dermoglyphidae (e.g., Dermoglyphus n. sp.,
Figure 52) the processes are in the form of two large circular lobes that join medially through a short base. In Psoroptes (Figures 65, 67) the processes are also fused basally. Distally they are ribbed lobes with attenuate tips. Medially there arise, from the base of the pro cesses, a pair of finger-like projections. The members of the family
Rosensteiniidae have paired, moustache-like lobes (e.g., Figure 69), except for Mydopholeus capillus McDaniel and Baker. In this species the processes are circular in outline (Figure 70).
Pseudorutellar processes are also present in members of the family
Anoetidae • In these mites the processes are of the moustache type and are fused medially. The edge of the processes is provided with a deli cate fringe (Figure U9).
The pseudorutellar processes of the Proctophyllodidae appear to arise from the ventral surface of the pseudorutella as fan-shaped, hyaline lobes (Figure 50). The dorsal surface of each process bears a raultidigitate projection. The dorsally recurved portion of the pseudorutella is well developed by the ventral part is reduced to an acute, sclerotized projection.
In Yunkeracaridae (Figure 53; psr) and Cytonyssus (Cytoditidae)
(Figure 5U; psr) the pseudorutella are reduced to small, acute pro jections. In the yunkeracarids the lateral lips persist as a short, rounded lobe (Figure 53; LL); they appear to be entirely absent in
Cytonyssus , In Rhynchoptes anastosi Fain (Rhynchoptidae) (Figure 57), the entire subcapitulum is much elongated. The lateral lips are entirely
reduced. The pseudorutella are small but readily recognizablej pseudo
rutellar processes are lacking. The most striking feature of Rhyn
choptes, however, is the posterior inflection of the postlabrum (Fig ure 57; pstlbr) and pharynx (ph) into the propodosoma. The placement
of these structures is far basad of their usual position in acaridid mites.
The subcapitulum of Cytodites nudus (Cytoditidae) (Figures 55, 56)
is the most modified of those examined. The gnathosoma is pyriform in
outline and cylindrical in cross-section in this species. The major
part of the gnathosoma appears to be subcapitular in origin. The ven
tral surface is smooth and without recognizable pseudorutella or lat
eral lips (Figure 56). The dorsal cuticle of the gnathosoma is also
smooth and is continuous with the lateral and ventral surfaces of the
subcapitulum. Anteriorly, the dorsal wall is produced as a short, flat
lobe. The distal tip of the gnathosoma is covered with cuticle except
for a small circular opening (not visible in figures). On the dorso
lateral surface, at the origin of the palps, are the supracoxal setae
(elc p). Within the gnathosoma, just beneath the dorsal cuticle, is
a flat, bilobed sclerite. The form of this sclerite suggests its iden
tification as the postlabrum (Figure 55; pstlbr). The anterior portion of the postlabral sclerite could not be understood from the available
material; it is not clear, therefore, if a labrum is present. Beneath
the postlabrum is an oval, basally attenuated sclerite — the ventral
floor of the pharynx, or subpharyngeal sclerite. The relative size of 53 the pharynx suggests that the gnathosoma is essentially a sucking tube.
A study of the gnathosomal musculature of Cytodites would be rewarding.
In Linobia coccinellae (Figure 1*8) the pseudorutella are fused into a heavily sclerotized stylet-like structure (psr). The tip of the stylet is recurved, thus furnishing an anchoring device. The lateral lips (LL) are present as a small projection lying dorsad of the fused pseudorutella.
In the genus Mortelmansia the pseudorutella (and lateral lips ?) are fused into a short cone-like structure (Figure 59). The movable digits of the chelicerae rest in the trough of the fused pseudorutella.
In the mites of the genus Opsonyssus (Gastronyssidae) the lateral walls of the subcapitulum are produced as huge hook-like apophyses.
The form of these apophyses varies among the species of Opsonyssus as may be seen from the figures of 0. brutsaerti (Fain) (Figure 60),
0. asiaticus Fain (Figure 6l), 0. pbyllorhinae Fain (Figure 62), 0. eidoloni Fain (Figure 63), and 0. zumpti Fain (Figure 6U). Opsonyssus spp. are ocular parasites of bats and, presumably, the apophyses func tion as anchors. Similar apophyses are developed in males of Fon- secalges saimirii Fain (Psoroptidae - Cebalginae), a skin parasite of tamarins (New World monkeys).
Another type of subcapitular apophysis has been reported for the genus Listrophorus (Listrophoridae) by T. E. Hughes (195U). These apophyses are the well known "hair-clasping organs." They are medially curved, paired processes that, according to Hughes, originate on the venter of the subcapitulum. Study of various species of Listrophorus 5 U indicates, however, that the hair claspers originate on the venter of the propodosoma, Just basad of the gnathosoma.
In the Lemumyssidae and Opsonyssus the bases of the chelicerae are covered by a dorsal sclerite. This sclerite is a tectum (tct).
In Mortelmansia (Figure 58) the tectum is a raucronate, concave sclerite that, medially, reaches to the level of the bases of the supracoxal setae. Laterally the tectum is continuous, through what appears to be a synarthrodial membrane, with the dorsal wall of the coxistemum.
Basally it extends to the gnathos omal-idios omal articulation. The tectum of Opsonyssus is a flat sclerite. Laterally it extends the en tire length of the dorsal wall of the coxistemum, with which it is insensibly fused. The anterior margin is V-shaped in dorsal aspect.
The subcapitulum of Bdellorhynchus polymorphus exhibits sexual dimorphism. Although females were not available for study, it seems apparent from the figure given by Dubinin (1956; Figure 373A) that the subcapitulum of this sex is more or less similar to that of Procto- phyllodes (see Figure 50 of this study). In males of B. polymorphus
(Figure 51) the base of the subcapitulum extends far laterad of the origins of the palps. This basal expansion of the coxistemum is a device to accommodate the tremendously enlarged chelicerae of the male (e.g., Figure 18).
The chaetotaxy of the subcapitulum is amazingly constant through out the suborder. The ventral subcapitular setae (a) are present in all groups except the Cytoditidae (Figures 5U, 56) and Lemumyssidae
(Figure 59)* The supracoxal setae (elc p) are, apparently, invariably present. In the Cytoditidae the supracoxals are the only setae remain ing on the gnathosoma. As may be noted from various illustrations (Fig ures 5, 17, 18, 50, 52, 53, 55, 58, 60, and 67), the supracoxal setae vary considerably in form and size. Usually they are relatively short and simple. In the Glycyphagidae, N. Fam. (Fusacarus), and some Acar idae (Figures 5, 17), however, the supracoxals are quite long and barbed.
THE PALPS. The treatment of the palps of Caloglyphus berlesei provides an adequate description of the palps of members of the fami lies Acaridae, Canestriniidae, Carpoglyphidae, Chaetodactylidae, En- sliniellidae, Hyadesiidae, Lardoglyphidae, Rosensteiniidae, Sapro glyphidae, and N. Fam. (Scatoglyphus). This may be designated the
Acarus type. This type is characterized by the presence of distinct podomeres, three setae (d^, d2, v), a solenidion (omega), and the
"disti-ventral organ." This is illustrated for Caloglyphus berlesei
(Figure 13); Tyrophagus putrescentiae (Schrank) (Acaridae) (Figure 71); and Coleopterophagus procerus Berlese (Canestriniidae) (Figure 75).
Within the group characterized by possession of an Acarus type palp variation exists mainly in the size and form of the podomeres, setae
and the solenidion. Carpoglyphus lactis (Linnaeus) (Carpoglyphidae)
lacks the ventral seta of the basal podomere.
In the Glycyphagidae the palp is similar to the Acarus type. The
"disti-ventral organ" is absent and the tip of the palp bears two setae
and a solenidion. The two terminal setae are hollow and thin-walled but lack the internal lamellae characteristic of solenidia* In ap
pearance they resemble the terminal palpal setae of the type termed "eupathidia" by Grandjean (19^3j earlier (Grandjean, 1935b), these setae were named "acanthoides"). la mites with a palp of the Glycy- phagus type, the solenidion is situated between the eupathidia (Fig ures 72, 76, and 77). The Glycyphagus type palp is illustrated for
Glycyphagus domes ticus in Figure 72. Virtually identical palps are seen in the Ghortoglyphidae, N. Fam. (Fusacarus), Labidophoridae,
Pyroglyphidae, and, among the bird-associated families, in the Allopti- dae, Freyanidae, Proctophyllodidae, Pterolichidae, Pteronyssidae, and
Syringobiidae.
The palps of Anoetidae are the most distinctive of the Acaridei; that illustrated for Histiostoma polypori (Oudemans) (Figure 7U) is representative. The palp of this species consists of two podomeres but the podomerization is more apparent from the shape of the append age than from sclerotization. The basal podomere is stout and gla brous. The distal podomere is produced, on the paraxial surface, as a horizontal, fimbriate, fan-shaped lobe. Antiaxial of the lobe are situated two long setae. Except for size these setae are identical in appearance; they resemble eupathidia but their identification as such is uncertain.
In many species of ectoparasitic Acaridei the palps are but slightly modified from the Glycyphagus pattern. A common modification
(e.g., Epidermoptidae, Analgesidae, Psoroptidae) is the production of hyaline lobes at the tip of the palp (Figures 66, 78). Finger-like processes may be present on the lobe (e.g., Psoroptes cuniculi; Fig ure 66). These lobes may partially or completely overlay the terminal 57 setae as, for example, in Megnlniella gallinulae (Buchholz) (Analges- idae) (Figure 78).
In the Turbinoptidae (Figure 73) the palps are shortened but two podomeres are apparent. The eupathidia are lacking. In the Yunker- acaridae (Figure 53) the podomeres are coalesced and the eupathidia are absent. The Lemurayssidae (Figures 58, 59) and Opsonyssus (Gas- tronyssidae) (Figure 60) have the podomeres entirely fused. The solenidia and eupathidia are lacking.
In Linobia coccinellae (Figure U8) the palps are filiform and two well-developed podomeres are present. The ventral seta is absent, however, as are the eupathidia.
In Bdellorhynchus (Falculiferidae) (Figures 18, 5l; Pp) the palp retains two podomeres but the distal one is hypertrophied. This podo mere is produced as a large, fan-shaped, hyaline lobe. On the anti- axial surface of the lobe is borne a short cylindrical projection.
This projection has the lyrifissure at its base and at its distal end bears a hypertrophied seta, d^. The eupathidia and solenidion are present.
In Rhynchoptes anastosi (Fain) (Rhynchoptidae) (Figure 57) the palps lack setae and are provided with a series of ventral barbs.
Rhynchoptids are found attached by the mouth-parts to the skin of their hosts (mammals) and the palps apparently serve as an anchoring device.
The palps of the Cytoditidae are the most reduced of those stud ied. In both Cytodites nudus (Vizioli) (Figure 55; Pp) and Cytonyssus £8 andrei Fain (Figure $h; Pp) they are small, smooth lobes, Podomeriza- tion is not apparent and setae and solenidia are lacking.
Observations on the palpal musculature were made for Glycyphagus domesticus (Glycyphagidae), Psoroptes cuniculi (Psoroptidae), and
Meaalges Johnstoni Spory (Analgesidae), In these species the muscu lature is as was described for Caloglyphus berlesei,
GNATHOSCMAL STRUCTURES OF THE HETERQMORPHEC DEUTONIMPHS. The
Caloglyphus type of hypopial gnathosoma is the least reduced of those encountered in the present study. This structural pattern (Figures 1$,
16, 79) is characterized by a well developed, cylindrical subcapitulum, distinct palps, and a setal complement consisting of the supracoxal setae (elc p), the dorsal setae of the palps (d2 ), and the palpal solenidion (omega), A gnathosoma of this type has been observed in deutonymphs of Acaridae (Acarus, Caloglyphus, Lackerbaueria, Rhizo- glyphus), Carpoglyphidae (new genus "H")* and Lardoglyphidae. A some what reduced, but structurally complete, version of the type was found in Monieziella (Acaridae), In M. corticalis (Michael), the subcapitulum is a short, stout cylinder and the palps are small, poorly sclerotized lobes. In the hypopi possessing the Caloglyphus type of gnathosoma, considerable inter-specific variation has been observed in virtually every feature. These variations, when analyzed, will provide useful taxonomic characters.
Complete fusion of the palps to the subcapitulum and partial fusion to each other is seen in members of the genus Cosmoglyphus (Acaridae)
(Figure 80). A normal setal complement is retained, however. 59
The exoskeletal anatomy of the deutonymphal gnathosoroa in Anoetidae is quite distinctive* In almost all of the forms studied the gnathosoma is essentially similar to that illustrated for Bonomia sphaerocerae
Vitzthum (Figure 81) and Myianoetus mas corum (Linnaeus) (Figure 82).
Here the subcapitulum is an elongate cylinder to which the palps are completely fused. The setae present are the supracoxal pair and the solenidia (tremendously elongated in these mites). In Histiostoma himalyae (Vitzthum) the gnathosoma is of a less modified type than that of other anoetids studied. In this species the subcapitulum is relatively short and the palps are partially free (Figure 83). The chaetotaxy is as in other members of the family.
The hypopi of Chaetodactylidae and Ensliniellidae display a marked reduction in the gnathosoma. In Kennethiella trisetosa (Cooreman)
(Ensliniellidae) (Figure 8U) and Chaetodactylus osmiae (Dufour)
(Chaetodactylidae) the gnathosoma is represented by two small lobes on the venter of the prodorsum. These lobes bear two pairs of setae, one of which is the solenidia. If the lobes are assumed to represent vestiges of the palps it would follow that the other pair of setae is d2- Gnathosomal regression similar to that of the Ensliniellidae and
Chaetodactylidae is seen in Labidophoridae. In Labidophorus (Fig ure 85) and Myacarus the mouth-parts are reduced to two seta-bearing lobes. The setae are omega and (apparently) cb,. Of the endoparasitic hypopi of feather mites, Falculifer rostratus
(Bachholz) (Falculiferidae) and Gabucinia sp. (Pterolichidae) were studied. Both species lacked any trace of a gnathosoma.
In the immobile hypopi of Glycyphagus (Glycyphagidae) the gnatho soma is also entirely absent. DISCUSSION
INTERPRETATION OF THE ANATOMY OF THE GNATHOSOMA AND COMPARISON OF
ITS STRUCTURE WITH THAT OF OTHER ACARIFORM MITES. There exist, at present, two major theories purporting to explain the anatomy of the gnathosoma. The first of these is the Bomer-Snodgrass interpretation; a summary of this theory was published by Snodgrass (1
(2) the subcapitulum is a compound structure; (3) the dorsal portion of the subcapitulum is derived from elements of the ancient head, the labrum and postlabrum (epistome of Snodgrass); (U) the lateral and ventral portions of the subcapitulum are derived from the pedipalpal coxae and coxal endites; and (5) the pharynx is a preoral cavity, analogous to the insect cibarium.
The second theory of the gnathosoma is that of Grandjean (1957, and further restated by van der Hammen, 1961, 1961;). The main points of the theory are (1) the integument surrounding the chelicerae repre sents the ventral surface of body segment I and (2) the subcapitulum
(both dorsal and ventral surfaces) represents the ventral surface of segment II.
61 62
The Grandjean theory can be disposed of quickly. This interpreta tion, which demands that the mouth open in the middle of coxisternum
II, is based on a misunderstanding of the postlabral apodeme. van der
Hammen (19610 defines apodemes as "the internal extensions of the chi- tinous skeleton, arising from the borders of the segments.*1 Because the inflection of the postlabrum is an apodeme, this inflection must represent a segmental border— in this case, the border of segments I and II. The Grandjean interpretation is thus true by definition; un fortunately, the definition is false.
In the following discussion the gnathosoma of acaridid mites has been interpreted in terms of the BiJrner-Snodgrass theory.
The chelicerae of acaridid mites present no major problems in in terpretation. They display the normal arachnid pattern in that they are preoral in position and of a chelate-dentate type, at least in the free-living species.
The chelicerae of acaridid mites are two-segmented. The proximal segment includes the cheliceral shaft and the fixed digit. The distal segment is the movable digit. This segment has been interpreted as representing the pretarsus of a normal appendage by Grandjean (19U7) and Snodgrass (19l;8). The identification of the movable digit as the pretarsus is based on (1) the presence of a dicondylic articulation and (2) the presence of both levator and depressor muscles inserting on the digit. In earlier acarological literature the movable digit was usually interpreted as representing a tarsus. This interpretation is not consistent with the observation that the tarsi of normal 63 appendages lack both the dicondylic articulation and the levator muscle.
The structure and musculature of the movable digit of the chelicerae of acaridid mites are consistent with the identification of this segment as a pretarsus.
There are no criteria for recognition of the segmental composition of the proximal cheliceral segment in the Acaridei. Grandjean (1939,
19li7) has considered, on reasonable grounds, that the proximal segment in primitive acariform mites represents the fused trochanter-femur- genu-tibia-tarsus. The cheliceral sheaths are regarded as coxal in origin.
The setation of the chelicerae in Acaridei is of a reduced type.
In the more generalized acariform mites, two dorsal cheliceral setae are present. These setae, cha and chb, are illustrated in the figure of the chelicera of Palaeacarus appalachicus Jacot (Palaeacari:Palae- acaridae) (Figure 86). Presumably the single paraxial seta, ch1, of acaridid mites is homologous with one of these dorsal setae but it is not possible to determine with which one the homology exists.
Judging from the literature it would appear that the paraxial cheliceral spurs of acaridid mites are a unique development. Paraxial spurs are also present in Palaeacarus (Figure 86), however, and it is possible these structures have been overlooked in other acariform mites.
The subcapitulum in the Acaridei presents a number of modifica tions from that of more generalized acariform mites. These modifica tions are seen in the ventral, or pedipalpal, portion of the subcapi tulum. In the generalized condition the anterior portion of the venter 6U of the subcapitulum is produced distad in two lobes, the lateral lips
(LL). Presumably the lateral lips represent the endites of the pedi- palpal coxae. The dorsal surface of the lateral lips constitutes the ventral floor of the prepharyngeal space. The ventral surface is con tinuous with the pedipalpal coxisternum. Ventrally the lateral lips bear three pairs of setae, the adorals. Laterad of the lateral lips are borne a pair of hypertrophied setae, the rutella (ru). The ar rangement of the lateral lips, adoral setae, and rutella, as exhibited by Palaeacarus, are illustrated in Figure 88. Here the lateral lips are relatively large, bear the three pairs of adoral setae, and are flanked by only slightly hypertrophied rutellar setae. This arrange ment is considered a primitive one. Grandjean (1957) has traced, in magnificent detail, a graded series of forms representing various de grees of hypertrophy of the rutella. Beginning with forms such as
Palaeacarus, the series culminates in the higher oribatids where the rutella are tremendously hypertrophied and sire borne on antero-ventral
outgrowths of the pedipalpal coxisternum. This arrangement is shown
for Protokalumma depressum (Banks) (Oribatei:Parakalummidae) in Fig ure 89. Grandjean suggests that these grossly hypertrophied rutella
are involved in some way with the feeding process but what role they
may play is unknown.
In the least modified condition, the venter of the subcapitulum
of acaridid mites shows a superficial similarity to that of the higher
oribatids. The paired distal prolongations of the coxisternum resemble
the rutella of oribatids. In the Acaridei, however, these prolonga
tions are not hypertrophied setae, hence the designation pseudorute11a. 6 5
Between the pseudorutella is situated a small median structure.
On the basis of relative position, this structure is interpreted as a vestige of the lateral lips, a conclusion previously reached by T. E,
Hughes (1953) and Knulle (1959)* The adoral setae are completely lack ing. Because adoral setae are absent and because this structure is un paired, its identification as representing vestigial lateral lips is a
tenuous one. It would appear that only evidence from the embryogeny
of the subcapitulum could determine the correctness or falsity of the identification.
The supracoxal setae of the palp (elc p) are a characteristic feature of the Acariformes. A recent report of supracoxal setae in a mesostigmatid mite (Parasitiformes) by van der Hammen (196U) is based
on erroneous observations.
The structures of the dorsal face of the subcapitulum present no problems in interpretation. The identity of the labrum is established by the form, position, and musculature of the organ. The postlabrum is identified on the basis of position and musculature. The proximal por
tion of the postlabrum is apodemal. The labrum and postlabrum in free-
living Acaridei are virtually identical to those of the oribatid mites.
The trough-shaped pharynx seen in acaridids is characteristic of
acariform mites. The pharyngeal musculature is normal. In accordance with Snodgrass* interpretation, the entrance to the pharynx is here
considered to be a secondarily developed oral opening (mouth*). The
true, or embryonic, oral opening (mouth**) is at the entrance of the
oesophagus. The pharynx is thus a preoral cavity. 66
The pedipalpal telopodites, or palps, of acaridid mites are highly modified organs and, judging from the number of erroneous statements in the literature, have apparently provided a source of puzzlement for many acarologists. Even in their least modified form, such as that of
Glycyphagus domesticus (Figure 72), the palps differ strikingly from the basic acariform type. To appreciate this difference it is necessary to examine a generalized acariform palp such as that of Palaeacarus ap- palachicus. The palp of Palaeacarus (Figure 87) comprises 5 segments; these are the trochanter, femur, genu, tibia, and tarsus. The chaeto- taxy of these segments is 0-2-1-3-11; the tarsus bears a solenidion.
Near the base of the tarsus, on the dorsal surface, is located the palpal lyrifissure. A palp such as that of Palaeacarus has the gen eral form of a walking leg but the pretarsus is lacking.
As may be seen from the descriptions given earlier in this study a "relatively unmodified" acaridid palp is more or less filiform in shape and consists of two podomeres separated by a synarthrodial mem brane. The basal podomere bears a dorsal seta, a ventral seta, and, at the distal margin, a dorsal lyrifissure. A second dorsal seta is inserted in the synarthrodial membrane. The distal podomere bears three setae at its tip, of which one is a solenidion. There is no intrinsic musculature but a single extrinsic muscle, the palpal adductor, inserts on the base of the palp.
The first conclusion to be drawn from the above description is that the acaridid palp consists of a single segment on the criterion of musculature. It is hoped that this finding will lay to zest all 67 the reports in the literature of two-, three-, four-, and five-segmented palps in the Acariedi. The synarthrodial membrane is thus a false ar ticulation, a conclusion previously reached by Zakhvatkln (1953) and
Knulle (1959). This conclusion by the earlier authors was based on a criteron other than that of musculature, however. Whether this false articulation is a former intersegmental joint is another question. Two observations argue against the idea of the membrane as a former joint.
One of these is the insertion of the dorsal seta d^ in the membrane.
There is no known instance of a seta occurring in an intersegmental joint on an appendage in the Acari. The other observation that goes against the "former joint" idea is the presence of the dorsal lyri- fissure basad of the membrane. In the acariform mites (as was seen in the description of the palp of Palaeacarus), the tarsus of the palp bears a proximal, dorsal lyrifissure. There is no instance of the lyrifissure occurring in any other position. It was reliance on the lyrifissure as a landmark that led Zakhvatkin and Knulle to regard the articulation as a secondary subdivision of the tarsus. Zakhvatkin went a step further and concluded that the dorsal seta (here labeled d^) represented the proximal dorsal seta (culminal or cm in the notation of Grandjean, 1935b) of the endeostigmatid-oribatid palp.
The interpretation of the basal podomere of the acaridid palp is even more problematical than that of the distal podomere* It is not at all clear which segments are involved in the formation of the podo mere. A conventional interpretation would be that this podomere rep resents the trochanter, femur, genu, tibia, and proximal portion of the tarsus of a normal palp. 68
As may be seen from the description of Caloglyphus berlesei and the comparative review, the mouth-parts of the heteromorphic deuto- nymphs differ markedly from those of the homeomorphic stases. The present study represents the first attempt to describe all of the components of the deutonymphal gnathosoma in terms of the morphology of the mouth-parts of the other stases. This interpretation is based on relatively unmodified mouth-parts such as those of Caloglyphus and has been extended to the more regressed types.
The cylindrical basal unit of the gnathosoma is here interpreted as homologous with the subcapitulum of the homeomorphic stases. This interpretation is based on the form of this unit and its spatial re lations with the idiosoma, Oudemans (1917) reached the same conclu sion; he referred to the subcapitulum as "de beide maxillae.11 In common with the subcapitulum of the other stases, that of the deuto- nymph bears basal apodemes and a pair of supracoxal setae.
The origin and homology of the dorsal wall of the subcapitulum is unknown. It may represent the fused labrum and postlabrum.
The pair of appendages borne on the distal end of the subcapitu lum are considered to be the homologues of the palps, a conclusion also stated by Oudemans (op. cit.). The palps show considerable simi larity to those of the other stases. They are filiform and bear a dorsal lyrifissure, a dorsal seta, and a solenidion. If the lyri fissure is a reliable landmark the dorsal seta is a homolog of dg of the other stases. The palpal setae d^ and v are absent. 69
The lack of a mouth (or any oral opening) indicates that the deutonymph is a non-feeding stasis. Correlated with the absence of the mouth is the lack of chelicerae and a pharynx. It would appear that the gnathosoma of the deutonymph serves largely as a chemo- sensory and tactile organ, functions carried out by the setae of the palps.
INTERPRETATION OF THE COMPARATIVE STUDIES. As a background for a discussion of the comparative anatomy of gnathosomal structures in acaridid mites, several kinds of information are needed. There should be available a sound taxonomic system based on large numbers of attri butes. If historical aspects are to be considered, there should be available some sound hypotheses concerning the phylogeny of the group.
Finally, there should be a detailed body of knowledge concerning the feeding habits and other aspects of the ecology of these mites. None of these is available. The classification adopted in this study is an attempt to recognize a series of homogeneous families (the Pterolich- idae and Psoroptidae are the most likely exceptions to the attempted homogeneity) but a satisfactory suprafamilial classification has not been achieved. Phylogenetic speculation is virtually non-existent in the literature on Acaridei (with an important exception noted below).
Precise knowledge of feeding habits is also scarce. In its place, acarologists have attempted to infer feeding habits from habitat data, a risky procedure.
One of the purposes for which a comparative study may not serve is to provide a basis for a revision of existing classifications 70
solely on the data of that study. The data of a comparative study
may, however, be used to examine current classifications for con
gruency between the existing information and the newly gathered facts.
This can be done for certain aspects of two recent classifications of
Acariedi, those of Yunker (19$$) and A. M. Hughes (1961). Such an ex
amination seems appropriate because of the unsettled nature of the
suprafamilial classification of these mites.
In Yunker*s scheme, the Acaridei were arrayed in three major
groups (cohorts): the Acaridia, the Ewingida, and the Psoroptidia.
The first group comprised the free-living and insect-associated forms
(the Acaroid (except Ewingiidae and Pyroglyphidae), Anoetoid, and
Hemisarcoptoid groups as used in the list of Materials); the second
contained the Ewingiidae; and the third was composed of all the vertebrate-associated families. This classification implies that
the Anoetidae shares more characters in common with the Acaridae than
does the Ewingiidae. This is not true of the mouth-parts. The acarids
and ewingiids have similar palps and chelicerae and lack the pseudo-
rutellar processes. Both of these groups differ in these respects
from the anoetids. It may be added that characters of the idiosoma
and legs are, in this instance, in agreement with those of the mouth-
parts. Yunker*s placement of the Glycyphagidae in one cohort and the
Pyroglyphidae in another is also questionable in view of the similar
ity of the mouth-parts of these mites.
In her classification of 1961, Hughes separates, as superfamilies,
the Ewingiidae and the Acaridae (her Tyroglyphidae). Her Acaridae, 71 however, includes glycyphagids, labidophorids, chortoglyphids, etc.
This implies that Glycyphagus, for example, is more similar to Acarus than is Ewingia. Again, this is not true of the mouth-parts. Both
Hughes and Yunker include the genus Carpoglyphus in the Glycyphagidae
(or -inae). The mouth-parts of members of this genus, however, are very similar to those of the Acaridae and do not at all resemble those of the glycyphagids.
The above remarks suggest that some of the groupings of free-living acaridids previously utilized, as well as the "Acaroid group" of this study, are not satisfactory. When the palps, chelicerae, and sub- capitula are considered, the Acaroid group breaks into two groups.
These are an Acarus group (Acaridae, Canestriniidae, Carpoglyphidae,
Chaetodactylidae, Ensliniellidae, Ewingiidae, Hyadesiidae, Lardo- glyphidae, Rosensteiniidae, Saproglyphidae, and N. Fam. (Scatoglyphus)) and a Glycyphagus group (Chortoglyphidae, N. Fam. (Fusacarus), Glycy phagidae, Labidophoridae, and Pyroglyphidae). It will be interesting to see if future studies, based on large numbers and all kinds of characters, will support this division of the free-living acaroids.
The division of the acaroids also has bearing on speculations concerning phylogeny within the Acaridei. It is generally thought, and justifiably so, that the mo d e m array of acaridids have an origin in an ancestral group that resembled the present free-living forms.
But if the free-living forms are themselves heterogeneous which group among them can suggest the primitive character states? If acariform mites such as Pachygnathus (Endeostigmata) and Palaeacarus (Palaeacari) are considered to retain many primitive character states, then the aca ridids whose mouth-parts differ least from the primitive acariform con dition are members of the Glycyphagus group. Two conclusions follow from this. One, already mentioned in the first part of this Discussion, is that even the most primitive of a;aridid mouth-parts are very much modified from those of their presumed acariform progenitors. The second is that there are no primitive acaridid mites. By "primitive" is meant the retention of a large number of characters in the primitive state as compared to other members of the group. While the organization of the mouth-parts of members of the Glycyphagus group may be considered primi tive, the features of the idiosoma and legs of these mites are probably not so nearly "primitive" as those of the Acarus group.
A second major phylogenetic hypothesis concerning Acaridei is that of Pain (1962). Fain has suggested, and many acarologists would agree, that the various groups of ectoparasitic acaridids have been derived from an ancestral form similar in habit and structure to the modem genus Dermatophagoides (Pyroglyphidae). Members of Dermatophagoides occur in stored food products and nests of birds and mammals. At least one species is known to feed on a vertebrate — man — as may be seen in the gruesome account by Traver (1951). Their mouth-parts are of the Glycyphagus type. On the paraxial face of the chelicera is a small cheliceral hood, a presumed forerunner to the more elaborate cheliceral hoods of various parasitic forms. The chelae do not differ greatly from those of parasitic species such as the Chorioptinae
(Psoroptidae). The pseudorutella are short and do not form an 73 attenuate feeding tube as in the more modified Acarus type of subcapi tulum. The palp bears two eupathidia and a solenidion at the tip (Gly cyphagus type). This last condition is seen in many of the parasitic groups and it is simpler to imagine the origin of the palp of, say,
Psoroptes from that of Derma tophagoides than from that of Acarus.
Whether or not all of the parasitic groups have the same origin is another question. There is considerable diversity in these mites and the relationships of most families are uncertain. Some of the more interesting modifications of their mouth-parts are considered below.
Loss of the fixed digit of the chelicera has occurred at least four times in the Acaridei. Independent evidence indicates that the families in which it has occurred — Linobiidae, Laminosioptidae, Cyto- ditidae, and Leraurnyssidae — are not closely related. Linobia cocci- nellae, the only known species in the family, lives on a beetle, Mela- soma populi j presumably as an ectoparasite. Linobia is related to the
Canestriniidae. Laminosioptes cysticola, also the only known species in its family, lives in muscle of fowl. The Laminosioptidae is closely related to the quill-inhabiting members of the family Dermoglyphidae.
Cytoditids and Leraurnyssids are found in the respiratory passages of birds and lemurs, respectively. The relationships of both families are uncertain.
The marked posterior inflection of the pharynx and the postlabral apodeme in the Rhynchoptidae is not unique among Acariformes, The sup posedly primitive oribatid mite Haplochthonius simplex (luELllmann) (Ori- batei:Haplochthoniidae) and Paralycus (EndeostigmatasPediculochelidae) (See Appendix I) also have an enlarged postlabrum that is inflected into the propodosoma. All of these are rather small mites and it is tempting to suggest that the hypertrophy of the postlabrum is a device to provide more area for the attachment of pharyngeal dilator muscles.
The discovery of a tectum in Opsonyssus (Gastronyssidae) and the
Lemuroyssidae is of especial interest. Tecta are generally thought to be absent in acariform mites. A tectum has been observed in Psorergates
(Eleutherengona:Psorergatidae) (unpublished) and this observation, cou pled with the finding of tecta in acaridid mites, suggests that these structures may be more frequently encountered.
The gnathosoma of Cytodites nudus (Gytoditidae) is strikingly re duced and, in certain respects, more regressed than that of some hypopi.
As in the case of hypopi the origin of the dorsal gnathosomal wall is unknown. Although the gnathosoma may be compared with that of a hy- popus it should be noted that the gnathosoma of the heteromorphic deutonymph is essentially a tactile and chemo-sensory structure. The gnathosoma of Cytodites is essentially a sucking tube. Because che licerae are lacking, manipulation of pieces of tissue (C. nudus lives in the lungs and air sacs of fowl) is impossible. Presumably the entire feeding process is accomplished through extra-oral digestion
(or, perhaps, the food is liquid in its original form).
Comparative study of the gnathosoma of hypopi reveals a clear trend toward even further regression in this structure. The degree of regression in the gnathosoma is generally correlated with the na ture of the host association of the mite. H(ypopi are phoretic on arthropods and mammals and endoparasitic in birds* In a number of in stances the homeomorphic stases live in close association with a host animal. Examples are the Ensliniellidae (in nests of solitary wasps), the Chaetodactylidae (in nests of xylocopine bees), the Labidophoridae
(in nests of small mammals), and the Falculiferidae (in the feathers of birds). The presence of the homeomorphic stases in precisely the same habitat as the potential host (or actually on the host, as in feather mites) greatly lessens the problems of host seeking in the deutonymph.
Thus, it is not surprising that the hypopi of these mites have the gnathosoma strongly regressed or absent.
The gnathosoma is also absent in hypopi of the genus Glycyphagus but these mites are not phoretic. In this instance the mites are inert during the entire deutonymphal stasis. SUMMARY
The mouth-parts of mites of the suborder Acaridei are of a modi fied acariform type. The mouth-parts, or gnathosoma, comprise the chelicerae and the subcapitulum. The pedipalpal telopodites, or palps, are borne on the subcapitulum.
The chelicerae are paired, preoral appendages. Each chelicera con sists of the cheliceral sheath and the chelicera proper. The chelicera proper is two-segmented j the segments are the shaft plus the fixed digit and the movable digit, or pretarsus. The processes of the chelicera are a paraxial seta and spurs, and ventral apophyses. In various ectopara- sitic species, other processes, such as a paraxial cheliceral hood and a dorsal hyaline process, may be developed. Major modifications of the chelicerae include elongation of the digits and accompanying loss of dentition, loss of the fixed digit, and complete reduction of the chelicera.
Mites of the family Falculiferidae display inter- and intra-sexual polymorphism in the chelicerae. The chelicerae of normal males re semble those of the females, while the chelicerae of polymorphic males differ in size and form. In Falculifer, it is shown that the chelicera-idiosoma size relationship is one of positive allometry.
The subcapitulum is considerably modified from the basic acari form pattern as seen in the Endeostigmata and the Oribatei. In the
76 77 acaridids the rutella and two pairs of ventral coxisternal setae are lacking. The lateral lips are reduced to a median, unpaired vestige that lacks the adoral setae. In place of the rutella, there are developed antero-ventral outgrowths of the subcapitulum, the pseudo- rutella. In various parasitic species elaborate, hyaline, pseudo- rutellar processes may be present. In some mammal-infesting ecto parasites, hook-like subcapitular apophyses are developed.
The supracoxal setae of the palp are invariably present but vary markedly in size and form throughout the suborder.
Three basic patterns can be recognized among the palps of acaridid mites. In each of these types the palp is single segmented but com prises two podomeres; the basal podomere bears a lyrifissure. Palps of the Glycyphagus type and the Acarus type have a dorsal and a ventral seta on the basal podomere; the distal podomere bears a single dorsal seta. These types differ in that in the former the tip of the palp bears three setae, of which one is a solenidion, and, in the latter, the palpal tip bears a single solenidion and a structure of uncertain nature, the "disti-ventral organ.'1 In the Histiostoma type the distal podomere is produced laterally as an elaborate fan-shaped process; the podomere bears two hypertrophied setae. Setae are lacking on the basal podomere. It appears that the various modifications of the palps can be derived from a Glycyphagus type.
The mouth-parts of the heteromorphic deutonymphs differ markedly from those of the homeomorphic stases. In the least modified form the gnathosoma of hypopi comprises a subcapitulum and paired palps. The 78 palps bear two setae, a solenidion, and a lyrifissure. Modifications of this basic plan are regressive and in some species the gnathosoma is entirely absent.
Detailed study of the various components of the gnathosoma pro vides numerous taxonomic characters of potential value at all levels of classification. An examination of the mouth-parts of the Pediculo- chelidae has resulted in the transfer of this family from the Acaridei to the Endeostigmata. APPENDIX I
THE MOUTH-PARTS OF PARALYCUS WCMERSLEY
( = PEDICULOGHELUS LAVOIPIERRE) (PEDICULOCHELIDAE)
In 1905 Berlese described as Alicus (sicl) pyrigerus the first representative of the then unnamed genus Paralycus. At that time the genus Alycus Koch was composed of a heterogeneous assemblage of endeostigmatid mites. In 19UU Womersley, in a key to the genera of
"Alycidae," created the name Paralycus for Berlese’s A. pyrigerus.
Lavoipierre, in 19k&, created the genus Pediculochelus for P. raulti, a new species collected from a bee’s nest in Natal, South Africa.
That author regarded this mite as representative of a new family,
Pediculochelidae, which was compared with the Tarsonemidae. In
19^2, Baker and Wharton, on the basis of new material identified as
P. raulti, placed the Pediculochelidae in the Acaridei and suggested that it perhaps occupied a position intermediate between the Acaridei and Oribatei. Dubinin (195U), in a revision of the Acaridei, erected a new superfamily, Pediculocheloidea, for these mites. Shortly there after Yunker (1955), unaware of Dubinin's prior action, also raised the Pediculochelidae to superfamilial rank. This classification of
Dubinin and Yunker was followed by Baker et al. (1958) and A. M.
Hughes (1961) as regards the acaridid affinities of the Pediculo chelidae. No recent author has recognized that Paralycus pyrigerus
19 80
(Berlese) is congeneric with Pedicnlochelus raulti Lavoipierre and none has questioned Baker and Wharton’s placement of Pediculochelus despite the fact that these mites bear no resemblance to Acaridei.
It is apparent that Berlese’s original placement of his A. pyrigerus in the "Alycidae" has more correctly reflected the relationships of this genus than have the actions of any subsequent worker. In view of the recent solidarity of opinion on the position of the Pediculo chelidae it is important to note that only Baker and Wharton’s opin ions were based on actual examination of specimens. In my own studies it has been possible to examine virtually all known material of these mites. This includes the type of Alicus pyrigerus Berlese (Typico
30/12 in the Berlese Collection), a holotype and paratype of Pediculo chelus raulti Lavoipierre, and the specimens from Rattus from Florida and Gallus from Samar reported by Baker and Wharton (1952). There is uncertainty as to the number of valid species included in the above material but no hesitancy is felt in regarding all of the specimens as congeneric. The following description of the mouth-parts is appli cable to the genus Paralycus as a whole.
Chelicerae (Figure 90). The chelicerae are short, stout, lightly sclerotized and of the chelate-dentate type. Two setae are borne on the dorsal surface of the chelicera; the anterior seta (cha) is pro cumbent and the posterior (chb) is erect. The fixed and movable digits bear, respectively, two and one teeth in addition to the terminal hooks. 81
Subcapitulum (Figure 91). The labrum is of the normal type: smooth, elongate, and tapering to a rounded tip. The postlabrum is a large, oval sclerite; posteriorly it is inflected to just beyond the level of the prodorsal trichobothria.
The supracoxal setae are short and rod-like.
The ventral surface of the subcapitulum (Figure 91) is lightly sclerotized and bears the usual three pairs (a, m, h) of subcapitular setae. The lateral lips are short, hyaline, tapered, and bear two pairs of adoral setae. Laterad of the lateral lips are borne the rutella. These are short, blunt, curved dorsad, and bear a single dorsal tooth.
The palps are five-segmented and of the normal configuration.
The palp chaetotaxy is (trochanter to tarsus): 0-2-0-1-9; the tarsus bears a solenidion. This is a normal endeostigmatid-oribatid palp chaetotaxy except for the absence of the dorsal seta of the genu and the two latero-ventral setae of the tibia.
From the above description and accompanying figures it can be seen that the mouth-parts of Paralycus differ markedly from those of the Acaridei. The differences are:
1. the presence of two dorsal setae of the chelicera;
2. the presence of well-developed lateral lips and two pairs of adoral setae;
3. the presence.of rutella;
U. the presence of three pairs of ventral subcapitular setae;
5. the presence of five-segmented palps with a more or less normal chaetotaxy. It may be noted that these features also differentiate Paralycus from the Tarsonemini (to which group these mites were assigned by
Lavoipierre, 1J?U6). The structure of the mouth-parts, legs, and idiosoma are, however, in general agreement with those of the sub order Endeostigmata (see Grandjean, 1939) and it is here suggested that the Pediculochelidae be transferred to that group. APPENDIX II
GLOSSARY OF SOME TERMS PERTAINING TO THE MOUTH-PARTS OF THE ACARIDEI AND OTHER ACARIFORM MITES adoral setae — paired setae of the ventral surface of the lateral lips; 1-3 pairs may be present. antiaxial — relatively farther from the longitudinal axis of the body. apotele — the pretarsus (q.v.). capitular apodeme — the postlabral apodeme (q.v.). capitular setae — subcapitular setae (q.v.). capitulum — the gnathosoma (q.v.). cervix — the postlabrum (q.v.). chelate — with apposed cheliceral digits. chelate-dentate — with the cheliceral digits apposed and provided
with teeth. chelicerae — the first pair of appendages in the Arachnida; these are (secondarily) preoral in position. cheliceral fossae (mandibular fossae) — paired depressions on the
dorsal surface of the subcapitulum in which the chelicerae rest. cheliceral frame — the integument immediately surrounding the bases
of the chelicerae and including the cheliceral
sheaths; bounded dorsally by the prodorsum and ventrally by the subcapitulum.
83 circumcapitular furrow — the articulatory (synarthrodial) furrow sepa
rating the subcapitulum and the idiosoma. coxistemum — a compound sclerite resulting from the fusion of coxal
and sternal elements; use of the term emphasizes not
only the compound nature of the sclerite but also the
impossibility of recognizing the limits of the com
ponent sclerites. epipharynx — the labrum (q.v.), epistome — the postlabrum (q.v.). external malae — the pseudorutella (q.v.). fixed digit — the dorsal, immovable finger of the chelicera. gnathobase — the pedipalpal coxistemum (q.v.). gnathocoxae — the pedipalpal coxae. gnathosoma — the body region comprised of the pedipalps and chelicerae. gnathosomal base — the pedipalpal coxistemum. hypostome — the paired lateral lips (q.v.). infracapitulum — subcapitulum (q.v.). labium — archaic term for the subcapitulum in whole or in part, labrum — the unpaired dorsal lip of the subcapitulum; characterized
by position and presence of retractor muscle. laterocoxal seta — the supracoxal seta (q.v.). laterolabial spine — the supracoxal seta (q.v.), lyrifissure — slit-like integumentary organ of unknown function. mandibles — an archaic term for the chelicerae, still much used
by European authors. 85 maxillary — an archaic term, of or pertaining to the pedipalpal
coxistemum.
mouth* — the postembryonic opening of the alimentary canal; the
anterior orifice of the pharynx in Arachnida.
mouth" — the true or embryonic mouth, situated just posterior to
the pharynx in postembryonic stases of Arachnida.
movable digit — the ultimate segment (pretarsus) of the chelicera,
articulated ventro-laterally with the base of the
fixed digit.
normal seta — a general designation for all setae other than
solenidia (q.v.).
omega — the general signature for tarsal solenidia.
palps (palpi) — the pedipalpal telopodites.
paraxial — relatively closer to the longitudinal axis of the body,
pedipalps — the second pair of appendages in the Arachnida.
pharynx — the preoral pump-like apparatus of the Arachnida; char
acterized by position and insertion of constrictor and
dilator muscles,
postlabral apodeme — the inflected (apoderaal) portion of the
postlabrum.
postlabrum — the dorsal sclerite of the subcapitulum; partially
apodemal; characterized by the origin of the labral
retractor and dorsal pharyngeal dilator muscles,
pretarsus — the terminal segment of a normal appendage; the movable
digit of the chelicera; characterized by a dicondylic articulation and the insertion of both depressor and
levator muscles. pseudorutella — the rutella-like antero-ventral projections of the
subcapitular coxistemum. pseudorutellar processes — the hyaline, flap-like ventral processes
of the pseudorutella. rutella — paired hypertrophied setae situated on the antero-dorsal
surface of the pedipalpal coxistemum. solenidion — thin-walled, distally blunt, hollow setae; typically
with a series of internal lamellae giving the seta a
cross-striated appearance; presumably chemo-sensory
in function. spur — tooth-like, non-chaetous, cuticular process on the paraxial
surface of the chelicera. subcapitular setae — the paired setae of the medio-ventral surface
of the subcapitulum. subcapitulum — the gnathosomal unit bounded dorsally by the labrum
and postlabrum, laterally and ventrally by the pedi
palpal coxistemum, antero-ventrally by the lateral
lips, and posteriorly by the circumcapitular furrow, supracoxal seta — the paired dorso-lateral seta of the pedipalpal
coxistemum. tectum — the roof-like dorsal portion of the gnathosoma; bounded
laterally by the pedipalpal coxistemum, posteriorly by
the circumcapitular furrow, and free anteriorly. APPENDIX III
LIST OF ABBREVIATIONS USED IN FIGURE LABELS a — subcapitular setae add pp — palpal adductor apd — apodeme aps — apophysis ch1 — paraxial cheliceral seta cha — distal cheliceral seta chb — basal cheliceral seta ch aps — cheliceral apophysis
Chel — chelicera ch fos — cheliceral fossa ch hd — cheliceral hood ch sh — cheliceral sheath ch sp — cheliceral spur cons ph — constrictor muscles of pharynx
Cxst — coxistemum dj — distal dorsal seta of palp d2 — basal dorsal seta of palp dil ph — dilator muscles of pharynx d ptr — pretarsal depressor elc p — supracoxal setaof palp elc I — supracoxal setaof legI
87 f d — fixed digit
Gna — gnathosoma hy pr — hyaline process
LL — lateral lips
1 ptr — pretarsal levator
Ls — labrum lyr — lyrifissure
M* — anterior opening of alimentary canal
M*1 — true mouth m d — movable digit omega — tarsal solenidion ph — pharynx
Pp — palp prd — prodorsum ps-art — pseudoarticulation psr — pseudorutellum psr pr — pseudorutellar process pstlbr ~ postlabrum ret lbr — retractor muscle of labrum ru — rutellum
Subc — subcapitulum subc aps ~ subcapitular apophysis subph ~ subpharyngeal sclerite tct — tectum v — ventral seta of palp x — disti-ventral organ of palp Figure 1 Caloglyphus berlesei (Michael) (ACARIDAE)
Anterior region of body of protonymphj
lateral. ch sh Chel prd
elc I Subc
VOo Figure 2 Caloglyphus berlesei (Michael) (ACARIDAE).
Chelicera of male; paraxial.
Figure 3 Caloglyphus berlesei, Chelicera of male;
antiaxial.
Figure U Caloglyphus berlesei. Chelicera of male,
showing musculature; antiaxial. 'ch aps
ch sh
3
4 93
Figure 5. Caloglyphus berlesei (Michael) (ACARIDAE).
Subcapitulum of female; dorsal. 9U
p*r
\\ 11 \V/
elc p o p t I
pstlbr
5 95
Figure 6. Caloglyphus berlesei (Michael) (ACARIDAE).
Subcapitulum of female; ventral. 96
6 Figure 7. Caloglyphus berlesei (Michael) (ACARIDAE).
Cheliceral dentition of male; antiaxial. 98 99
Figure 8 Caloglyphus berlesei (Michael) (ACARIDAE).
En face view of distal portion of sub
capitulum of female. ch fos
I! 100 Figure 9 Caloglyphus berlesei (Michael) (ACARIDAE),
Labrum and pharynx of female; sagittal
section.
Figure 10, Caloglyphus berlesei. Lateral lips and
pseudorutella; transverse section. cO 103
Figure 11. Caloglyphus berlesei (Michael) (ACAEIDAE).
Subcapitulum of female; transverse section
at level of pharynx. >dil ph
11 10$
Figure 12. Caloglyphus berlesei (Michael) (ACARIDAE).
Subcapitulum of female; posterior. CM 107
Figure 13. Caloglyphus berlesei (Michael) (ACARIDAE).
Palp of female; dorsal.
Figure lii, Caloglyphus berlesei. Extrinsic musculature
of palp of female; ventral. °6auio w Figure 15 . Caloglyphus berlesei (Michael) (ACARIDAE).
Gnathosoma of deutonymph; dorsal,
Figure 16. Caloglyphus berlesei, Gnathosoma of
deutonymph; ventral. om*go 110 Figure 17. Acarus farris (Oudemans) (ACARIDAE).
Anterior region of body of female;
lateral. 112
ch *h Ch*l N\
Subc
•Ic I Figure 18. Bdellorhynchus polymorphus Trouessart
(FALCULIFERIDAE). Region of coxa I,
subcapitulum, and base of chelicera
of male; lateral. Ch«l
•le P
Subc
£ 18 115
Figure Schwiebia sp. (ACARIDAE). Gnathosoma
(partial) of female; lateral. Arrow
indicates longitudinal axis of idiosoma.
Figure 20, Glycyphagus destructor (Schrank)
(GLYCYPHAGIDAE). Chelicera of
fe male; paraxial, 116 117
Figure 21. Chortoglyphus arcuatus (Troupeau)
(CHORTOGLYPHIDAE). Chelicera of
female; paraxial,
Figure 22. Dermatophagoides passericola Fain
(PYROGLYPHIDAE). Chelicera of
female; paraxial, 118
>'zO; Figure 23. Carpoglyphus lactis (Linnaeus)
(CARPOGLYPHIDAE). Chelicera of
female; paraxial.
Figure 2U. Ewingia cenobitae Pearse (EWINGIIDAE).
Chelicera of female; antiaxial.
121
Figure 25. Histiostoma polypori (Ouderaans) (ANOETIDAE).
Chelicera of female; paraxial. 122
N. . 123
Figure 26, Hemisarcoptes malus (Shimer)
(HEMISARCOPTIDAE). Chelicera
of female; antiaxial.
Figure 27 . Linobia coccinellae (Scopoli)
(LINOBIIDAE). Chelicera of
male; paraxial, 26
// 125
Figure 28. Dermoglyphus elongatus (Megnin)
(DERMOGLYPHIDAE). Chelicera of
female; paraxial. 126
//
v
// 127
Figure 29. Syringobia chelopus Trouessart and Neumann
(SYRINGOBIIDAE). Chelicera of female;
paraxial. 128
cn CM 129
Figure 30. "Pteronyssus" simplex Haller (PTERONYSSIDAE).
Chela of female; paraxial.
Figure 31. Bychovskiata n. sp. (PTEROLICHIDAE). Chela
of female; paraxial. 130
ch hd
ch hd
31 131
Figure 32 • Ardeacarus ardeae (Canestrini) (PTEROIHCHIDAE).
Chela of female; paraxial.
Figure 33, Psoralges libertus Trouessart (PSOROPTIDAE-
Psoralginae). Chela of female; antiaxial. \ J ch1 -ch
ch hd 133
Figure 314-, Proctophyllodes quadrisetosus Atyeo and
Braasch (PROCTOPHYLLODIDAE). Chela of
female; paraxial.
Figure 35 . Bdellorhynchus polymorphus Trouessart
(FALCULIFERIDAE). Chelicera of male;
paraxial. 13k
.ch hd
V.,
ch ap«'
35 135
Figure 36. Falculifer rostratus (Buchholz)
(FALCUUFERIDAE). Chelicera of
female; paraxial. 136 Figure 37. Falculifer rostratus (Buchholz)
(FALCULIFERIDAE). Chelicera of
polymorphic male; paraxial.
139
Figure 38. Otodectes cynotis (Hering) (PSOROPTIDAE-
Chorioptinae). Chelicera of male; paraxial.
Figure 39. Psoroptes cuniculi (Delafond) (PSOROPTIDAE-
Psoroptinae). Chela of female; antiaxial. 11*0
38
39 H a
Figure lj.0. Myocoptes musculinus (Koch) (MYOCOPTIDAE).
Chela of female; paraxial.
Figure 1|1. Listrophorus dozieri Radford (LISTROPHORIDAE).
Chelicera of male; paraxial.
Figure 1*2. Chirodiscoides caviae Hirst (LISTROPHORIDAE).
Chela of female; paraxial. 1U2
\S Ht3
Figure U3. Notoedres cuniculi (Gerlach) (SARCOPTIDAE).
Chelicera of female; paraxial.
Figure UJU. Knemidocoptes mutans (Robin) (KNEMEDOCOPTI-
DAE). Chelicera of female; antiaxial.
Figure kS. Pneumocoptes penrosei (Wiedman) (PNEUMOCOPTI-
DAE). Chelicera of female; paraxial. 43
44 115
Figure 1*6. Glycyphagus destructor (Schrank)
(GLYCYPHAGIDAE). Subcapitulum
of female; ventral.
Figure U7• Dermatophagoides passericola Fain
(PYROGLYPHIDAE). Subcapitulum
(partial) of female; ventral. li»6
46 11*7
Figure 1^8. Linobia coccinellae (Schrank) (LINOBIIDAE).
Subcapitulum of female; ventral.
11+9
Figure U9. Histiostoma polypori (Oudemans) (ANQETIDAE).
Subcapitulum of female; ventral. 150 Figure !?0. Proctophyllodes quadrisetosus Atyeo and
Braasch (PROCTOPHYLLODIDAE). Subcapitulum
of female; ventral. 152
o m e g a p sr p r
r\
50 153
Figure £l. Bdellorhynchus polymorphus Trouessart
(FALCULIFERIDAE)• Subcapitulum of
male; ventral.
155
Figure $2 • Dermoglyphus n. sp. (DERMOGLYPHIDAE).
Subcapitulum of female; ventral.
Figure 53. Yunkeracarus faini Hyland and Clark
(YUNKERACARIDAE). Subcapitulum of
female; ventral. 156
ptr pr
•le p
ptr
I" Figure 5U. Cytonyssus andrei Fain (CYTODITIDAE).
Gnathosoma of female; ventral.
Figure 55. Cytodites nudus (Vizioli) (CYTODITIDAE).
Gnathosoma of male; dorsal.
Figure 56. Cytodites nudus. Gnathosoma of male;
ventral.
159
Figure 57. Rhynehoptes anastosi (Fain) (RHYNCHOPTIDAE)•
Gnathosoma, trochanter I, and anterior region
of propodosoma of female; ventral. 160 CM
Subc
v/
pittbr 57 Figure 58. Mortelmansia longus Fain (LEMURNYSSIDAE).
Gnathosoma (and anterior portion of pro
dorsum) of femalej dorsal.
Figure 59. Mortelmansia longus. Gnathosoma (partial)
of female; ventral. 162
elc p
Chel ch ch
tct
pstlbr
/A // //
\ /
59 163
Figure 60. Opsonyssus brutsaerti (Fain) GASTRONYSSIDAE).
Gnathosoma and prodorsal shield of male;
dorsal. 16U
ch.i
tube a p t
tct
prd 165
Figure 61. Opsonyssus asiaticus Fain (GASTRONYSSIDAE).
Lateral subcapitular apophysis of female;
ventral.
Figure 62. Opsonyssus phyllorhinae Fain. Same as above.
Figure 63. Opsonyssus eidoloni Fain. Same as above,
Figure 61i. Opsonyssus zumpti Fain. Same as above. 166 167
Figure 65. Psoroptes cuniculi (Delafond) (PSOROPTIDAE-
Psoroptinae). Pseudorutellar process of
female; ventral.
Figure 66. Psoroptes cuniculi. Palp of female; ventral.
Figure 67. Psoroptes cuniculi. Subcapitulum of female;
ventro-lateral.
Figure 68. Psoroptes cuniculi. Labrum of female; dorsal. 168 omega
ptr pr 169
Figure 69 . Nycteriglyphus bifolium Strandtmann
(ROSENSTEINIIDAE). Pseudorutellar
processes of female; ventral.
Figure 70. Mydopholeus capillus McDaniel and Baker
(ROSENSTEINIIDAE), Pseudorutellar pro
cesses of female; ventral. 170 171
Figure 71. Tyrophagus putrescentiae (Schrank) (ACARIDAE).
Palp of female; ventral.
Figure 72. Glycyphagus domesticus (Degeer) (GLYCYPHAGIDAE).
Palp of female; antiaxial. 172
om ega
om ega 173
Figure 73 . Schoutedenocoptes aquilae Fain (TURBINOPTIDAE).
Palp of male; ventral.
Figure 7U . Histiostoma polypori (Oudemans) (ANOETIDAE).
Palp of female; dorsal. 17U
v.
\ V
73
74 175
Figure 75 . Coleopterophagus procerus Berlese
(CANESTRINIIDAE). Tip of palp of
female; ventral.
Figure 76 . Dermatophagoides passericola Fain
(PYROGLYPHIDAE). Same as above.
Figure 77. Chortoglyphus arcuatus Troupeau
(CHORTOGLXPHIDAE). Same as above.
Figure . Megniniella gallinulae (Buchholz)
(ANALGESIDAE). Same as above. 81 LL
oBauio
o Bsujo
m 177
Figure 79. Caloglyphus sp, (ACARIDAE). Gnathosoma
of deutonymph; ventral.
Figure 80. Cosmoglyphus sp. (ACARIDAE). Gnathosoma
of deutonymph; ventral. 178 179
Figure . Bonomia sphaerocerae Vitzthum (ANOETIDAE).
Gnathosoma of deutonymph; ventral.
Figure 82 . Myianoetus muscarum (Linnaeus) (ANOETIDAE).
Gnathosoma of deutonymph; ventral.
Figure 83, Histiostoma himalayae (Vitzthum) (ANOETIDAE).
Gnathosoma of deutonymph; ventral. omega
Subc 181
Figure 8I4. Kennethiella trisetosa (Cooreman)
(ENSLINIELLIDAE). Anterior portion
of prodorsum of deutonymph; ventral.
Figure 85. Labidophorus sp. (LABIDOPHORIDAE).
Gnathosoma of deutonymph; ventral. 182
omega 183
Figure 86. Palaeacarus appalachicus Jacot (Palaeacari:
PALAEAGARIDAE). Ghelicera of female; par
axial.
Figure 87. Palaeacarus appalachicus. Palp of female;
anbiaxial. 18U
«bb
cha
86
81 Figure 88 . Palaeacarus appalachicus Jacot (Palaeacari
(PALAEACARIDAE). Subcapitulum (partial)
of female; ventral.
Figure 89 , Protokalumma depressum (Banks) (Oribatei:
PARILIKALUMMIDAE). Subcapitulum of female;
ventral. 186 L* ru
! t A yl
89 Figure 90. Paralycus raulti (Lavoipierre) (Endeostig
mata:PEDICULOCHELIDAE). Chela of female;
antiaxial.
Figure 91. Paralycus raulti. Subcapitulum of female
ventral. 90 REFERENCES CITED
Andre, M. 19b9* Ordre des Acariens. In P, Grasse, Traite de Zoologie, Tome VI:79h-892, 2 Pis., Masson et Cie, Paris.
Baker, E. W., J. H. Camin, F. Cunliffe, T. A. Woolley, and C. E. Yunker. 1958. Guide to the Families of Mites. Contrib. 3, Inst. Acarol., Univ. Maryland, College Park. 2U2 p.
Baker, E. W. and F. Cunliffe. I960. Notes on saproglyphid mites asso ciated with solitary wasps (Acarina:Saproglyphidae). Proc. Entomol, Soc. Wash. 62:209-231.
Berlese, A. 1897. Ordo Cryptostigmata (Sarcoptidae). In Acari Myria- poda et Scorpiones Hucusque In Italia Reperta, Portxci, 1-190, Tab. I-XV.
Berlese, A. 1905. Acari nuovi. Materiali pel Manipulus V. Redia II: 231-238.
Dubinin, V. B. 1951. Feather mites (Analgesoidea). I. Introduction to their study. In Fauna of the USSR VI(5):1-363. (in Russian)
Dubinin, V. B. 1953. Feather mites (Analgesoidea). II. Families Epi- dermoptidae and Freyanidae. In Fauna of the USSR Vl(6):l-Ull. (in Russian)
Dubinin, V. B. 195U. New classification of mites of the superfamily Analgesoidea and their position in the order Acariformes A. Zakv. 1952. Izvestia Akad. Nauk SSSR Ser. Biol. 195U : 59-75. (in Russian)
Dubinin, V. B. 1956. Feather mites (Analgesoidea). III. Family Pterolichidae. In Fauna of the USSR VI(7):l-l8U. (in Russian)
Ericson, R. 0, 1961. A glossary of some foreign-language terms in Entomology. U. S. Dept. Agr. Handbook 218:1-IV, 1-59.
Evans, G. 0., J. G. Sheals, and D. Macfarlane. 1961. The Terrestrial Acari of the British Isles. Vol. I. Introduction and Biology. British Museum (Nat. Hist.), London.
189 190
Evans, G. 0., A. Fain, and J. Bafort. 1963. Decouverte du cycle evolutif du genre Myialges avec description d'une espece nouvelle (Myialgidae:Sarcoptiformes). Bull. Ann. Soc. Roy. Entomol. 99: U86-500.
Fain, A. 1962. Un Acarien remarquable combinant les caracteres de plusiers families : Evansacarus lari n.g., n. sp. (Evansacaridae nov. fam. : Sarcoptiformes). Bull. Ann. Soc. Roy. Entomol. Belgique 98(9):125-lU5.
Grandjean, F. 1935a. Observations sur les Acariens (Ire Serie). Bull. Mus. Natl. Hist. Nat. 2e S., VII:119-126.
Grandjean, F. 1935b. Les poils et les organes sensitifs portes par les pattes et le palpe chez les Qribates. Premiere Partie. Bull. Soc. Zool. France LX:6-39.
Grandjean, F. 1937. Otodectes cynotis (Hering) et les pretendues trachees des Acaridiae. Bull. Soc. Zool. France 62:280-290.
Grandjean, F. 1939. Quelques genres d'Acariens appartenant au groupe des Endeostigmata. Ann. Sci. Nat., Zool. (Paris), lie Ser., II: 1-122.
Grandjean, F. 19U3. Le developpement postlarvaire d'Anystis. Mem. Mus. Natl. Hist. Nat., n.s., XVIII:33-77.
Grandjean, F. 19h7. L'origins de la pince mandibulaire chez les Acariens actinochitineux. Arch. Sci. Phys. Nat. 29:305-355.
Grandjean, F. 19U9. Observation et conservation des tres petits Arthropodes. Bull. Mus. Natl. Hist. Nat., 2 ser., XXI:363-370.
Grandjean, F. 1953. La coalescence femorogenuale chez Fusacarus (Acaridie, Acarien). Bull. Mus. Natl. Hist. Nat., 2 ser., XXV: 387-391*.
Grandjean, F. 195U. Essai de classification des Oribates (Acariens). Bull. Zool. Soc. France LXXVIII:li21-Ui6.
Grandjean, F. 1957. L'infracapitulum et la manducation chez les Ori bates et d'autres acariens. Ann. Sci. Nat., Zool., lie Serie: 233-281,
Hammen, L. van der. 1961. Description of Holothyrus grandjeani nov. spec., and notes on the classification of the mites. Nova Guinea, n.s., 10:173-19U.
Hammen, L. van der. 1961;. The morphology of Glyptholaspis confusa (Foa, 1900) (Acarida, Gamasina). Zool. Verhandel. 71:1-56. 191
Hughes, A. M. 1961, The Mites of Stored Food. Min. Agr. Fish. Food (London) Tech. Bull. 9:i-vi, 1-28?.
Hughes, R. D. and C. G. Jackson. 1958. A review of the family Anoeti- dae, Virginia J. Sci., n.s., 9:5-198.
Hughes, T. E. 1953. The functional morphology of the mouth parts of the mite Anoetus sapromyzarum Dufour, 1839, compared with those of the more typical Sarcoptiformes. Proc. Koninkl. Nederl, Akad. Wetensch.-Amsterdam, Ser. C, 56:278-287.
Hughes, T, E. 195U. The internal anatomy of the mite Listrophorus leuckarti (Pagenstecher, 1861). Proc. Zool, Soc. London 12U: 239-256.
Hughes, T. E. 1959. Mites, or the Acari. Athlone, London, i-viii, 225 p.
Johnston, D. E. 1965. A catalog of the determined species of Acari excl. Ixodides) in the collections of the Institute of Acarology. Ohio Agr. Expt. Sta. Dept. Zool. Entomol. Publ. Ser. 29: i-v, 1-66.
Knulle, W. 1959. Morphologische und entwicklungsgeschichtliche Unter- suchungen zum phylogenetischen System der Acari:Acariformes Zachv. II. Acaridiae:Acaridae. Grundlagen der Getreidemilben-Systematik. Mitt. Zool. Mus. Berlin 35:3h7-Ul7.
Lavoipierre, M.M. J. 19U6. A new acarine parasite of bees. Nature 158:130-131.
Lonnfors, L. 1930. Beitrage zur Morphologie der Analginen. Acta Zool. Fennica 8 :l-8l, Taf. 1-22.
Megnin, P. 1877. Monographie de la tribu des Sarcoptides psoriques. Revue Mag, Zool., Paris, 1*0:1-189, Pis. 1-13.
Michael, A. D. 1901. British Tyroglyphidae. Ray Soc., London, Vol. I, i-xvi, 291 p., 19 Pis.
Obussier, H. 1939. Beitrage zur Biologie und Anatomie der Wohnungs- milben. Z. Angew. Entomol. 26:253-296.
Oudemans, A. C. 1917. Acarologische Aanteekeningen UCEI. Entomol. Ber. IV(93):3Ul-3U8.
Oudemans, A. C. 1923. Studie over de sedert 1877 ontworpen system der Acari; nieuwe classificatie; phylogenetische beshouwingen. Tijdschr. Entomol. 66:1*9-85. 192
Robin, C. i860. Memoire zoologique et anatomique sur diverses especes d 1Acariens de la famille des Sarcoptides. Bull. Soc* Imp. Nat. Moskow XXXIII:l8U-293, Pis. 1-8.
Simpson, G. G., A. Roe, and R. C. Lewontin. I960. Quantitative Zoology. Harcourt, Brace and Co., New York, i-vii, I4I4.O p.
Scheucher, R. 1957. Systematik und Okologie der deutschen Anoetinen. In H. J. Stammer, Beitr&ge zur Systematik und fikologie Mittel- europaischer Acarina, Bd. I, Teil 1:233-38U.
Snodgrass, R. E. 19U8. The feeding organs of Arachnida, including mites and ticks. Smithson. Misc. Coll. 110:1-93.
Traver, J. R. 1951. Unusual scalp dermatitis in humans caused by the mite, Dermatophagoides (Acarina, Epidermoptidae). Proc. Entomol. Soc. Wash. 53:1-25.
Vitzthum, H. G. 1931. Acari. In Kukenthal's Handbuch der Zoologie 3 (2 ):1-160.
Vitzthum, H. G. 19UO-19U3. Acarina. Bronn1s Klassen und Ordnungen des Tierreichs, Band 5, Abt. lj., Buch 5:1-1011.
Womersley, H. 19Ui. Australian Acarina, families Alycidae and Nanor- chestidae. Trans; Roy. Soc. S. Austral. 68:133-lii3.
Yunker, C. E. 1955. A proposed classification of the Acaridiae (Acar ina iSarcoptiformes). Proc. Helm. Soc. Wash. 22(2):98-105.
Zakhvatkin, A. A. 19^1. Tyroglyphoidea. In Fauna of the USSR VI(1): i-v, 1-573 (Transl. A. Ratcliffe and A. M. Hughes, AIBS, Washing ton, 1959).
Zakhvatkin, A. A. 1953. Collected Scientific Works. Moskow Univ., 1*18 p. (in Russian)