Chapter II: Foreword (1)

People having only casual interest in insects usually express amazement when they learn how much is known about this most numerous group of animals. However, while entomologists have good reason to take pride in the accomplishments of their contemporaries and predecessors, they are more likely to be appalled by how much remains to be learned. We are indeed ignorant of even the identity of fully half and probably much more than half the total number of insect species. Of those that have been described, we have reasonably complete information about the behavior and basic environmental relationships for only a comparative few. The great majority of the remainder are known only from specimens found in museum collections. Such information as we have about these species usually amounts to no more than date and locality of collection.

This is true of the cockroaches, which now include approximately 3,500 described species. Conservative estimates based on partially studied museum collections and the percent of new species found in recent acquisitions, particularly from tropical and subtropical countries, indicate that at least 4,000 species remain unnamed. Although the group is well known in general terms to nearly all entomologists, there is an almost complete void of information about all except the few domestic species and, to a progressively diminishing degree, some 400 others. Many details about the lives of even those that share man's habitations are not fully understood. This then is a rough measure of how little is known about cockroaches.

With the exception of mosquitoes and a few other comparatively small groups of insects on which work has been concentrated, it is doubtful if any other comparable segment of the world's insect fauna is better known. Already an estimated 800,000 kinds of insects have been described, and since this figure is generally regarded as less than half the actual total, think what this means in terms of knowledge yet to be assembled. No wonder entomology is a growing science with a promising future, but the magnitude of the task also presents a serious obstacle to progress. Progress can continue only if the scattered literature resulting from the diversified labors of hundreds of contributors is brought together and summarized in thorough and well-organized compilations that can serve as a solid basis for future research.

The present work is such a compilation, for it assembles what has been gleaned from approximately 1,700 sources, including correspondence with a large number of other workers. Original observations during some eight years of concentrated effort in U. S. Army Quartermaster research laboratories are a valuable supplement to what others have done, and with this background of experience the authors are especially well qualified to appraise previous work. Seldom has a compilation been done so thoroughly or a single large group of insects been the subject of such uninterrupted effort.

The contents gives the categories of subject matter treated and the introduction discusses the value of this assembled information and offers suggestions for future study. No longer are cockroaches regarded only as disagreeable pests; many species appear to be important, actually or potentially, as carriers of disease. Recognition of this importance has grown considerably, even in the period since World War II. Consequently, anything that increases our knowledge of the basic bionomics of cockroaches will be consulted widely for factual information and for clues to new approaches.

In spite of this extensive compilation, the limitations of present information about cockroach bionomics must be kept in mind. The cited observations of many writers were fragmentary, or their conclusions disagreed. But it is fundamental to scientific inquiry that we should know and attempt to evaluate the results of previous study, and that is what Drs. Roth and Willis have done. Fortunately, their review is readily available. Sometimes, a piece of work fails to be of maximum value because the results are not generally accessible to later students. For this reason I am especially glad that the Smithsonian Institution, by disseminating the results of the authors' labors, has this opportunity to exercise one of its traditional functions--that of diffusing knowledge.

Throughout the period of research by Drs. Roth and Willis at Natick, I was in frequent correspondence with them, and I admire their many accomplishments. Our warmest commendations should go not only to them personally but also to those in administration who encouraged their fundamental research and who aided in the financial support of this publication.

ASHLEY B. GURNEY
_Entomology Research Division_
_United States Department of Agriculture_

CONTENTS
Page

Foreword iii

I. Introduction 1
Historical 2
Methods 4
Future work 5
Illustrations 7

II. Species of cockroaches 7

III. Ecological relationships 14
Cave habitats 16
Cavernicolous cockroaches 17
Cockroaches from burrows 23
Desert habitats 25
Desert cockroaches 27
Aquatic habitats 30
Amphibious cockroaches 31
Outdoor habitats 33
Cockroaches from outdoor habitats 35
Structural habitats 70
Land-based structures 73
Cockroaches associated with land-based structures 74
Ships 82
Cockroaches associated with ships 85
Aircraft 87
Cockroaches associated with aircraft 88

IV. Classification of the associations 91

V. Mutualism 96
Bacteroids 96
Cockroaches in which bacteroids have been found 99
Bacteria 100
Protozoa 101

VI. Viruses associated with cockroaches 103

VII. Bacteria associated with cockroaches 104

VIII. Fungi and yeasts 127
Fungi associated with cockroaches 129

IX. Higher plants associated with cockroaches 139
Damage to plants by cockroaches 162

X. Protozoa associated with cockroaches 166

XI. Helminths associated with cockroaches 190
Helminths for which cockroaches serve as primary hosts 192
Helminths for which cockroaches serve as intermediate
hosts 203
Helminths whose eggs have been carried by cockroaches 208

XII. Arthropoda associated with cockroaches 210
Arachnida 211
Chilopoda 222
Insecta 224
Hymenoptera 234
Predators and parasites of cockroach eggs 234
Host selection by egg parasites 254
Cockroach-hunting wasps 255
Ants predaceous on cockroaches 266

XIII. Vertebrata associated with cockroaches 268
Pisces 268
Amphibia 269
Reptilia 272
Aves 276
Mammalia 283

XIV. Checklist of cockroaches and symbiotic associates 290

XV. Cockroaches as commensals 310
Hosts of commensal cockroaches 310
Checklist of commensal cockroaches with their hosts 315
Obscure associations 316

XVI. Cockroaches as predators 319
Interspecies predation 319
Intraspecies predation 322

XVII. Associations among cockroaches 324
Familial associations 325
Gregariousness 330
Intraspecies fighting 336
Interspecies compatibility 337
Interspecies antagonism 341

XVIII. Defense of cockroaches against predators 343

XIX. The biological control of cockroaches 348
Invertebrates 349
Vertebrates 353

Acknowledgments 354

References 356

Index 441

THE BIOTIC ASSOCIATIONS OF
COCKROACHES[1]

BY LOUIS M. ROTH AND EDWIN R. WILLIS[2]

_Pioneering Research Division, United States Army
Quartermaster Research and Engineering Center
Natick, Mass._

(With 37 Plates)

With most of us collectors the life history of an insect begins in
the net and ends in the bottle.

HANITSCH (1928)

I. INTRODUCTION

Recently we brought together much of the literature linking cockroaches with the transmission of certain organisms that cause disease in man and other vertebrates. In that paper (1957a) we concluded that cockroaches, being potential vectors of pathogenic agents, should not be regarded simply as minor annoyances. Obviously the associations of cockroaches with agents of vertebrate diseases are of more immediate importance than their relations with pathogens of lower animals or with nonpathogens. On the other hand, cockroaches are of general economic as well as medical importance, and their control is sought by many who are unaware of their medical significance. That the control of domiciliary cockroaches is far from satisfactory may be inferred from current entomological and pest-control journals in which new insecticides are continually advocated to replace others found to be inadequate. Possibly new approaches to the control of cockroaches are needed. Whether these lie in the direction of increased use of parasites and predators for the biological control of these insects remains to be seen. In any event, the more we know about any insect, especially its ecology, the greater the likelihood of achieving satisfactory control. In order to advance knowledge in any field of science, new research should proceed from the results of prior investigations when these exist. We hope that the observations and experiments cited herein may suggest areas for future research and exploitation.

To the best of our knowledge no previous publication has brought together the vast literature on the parasites, predators, commensals, and other symbiotic associates of the Blattaria. For this reason, we have tried to assemble observations on all such known associations. Undoubtedly we have overlooked some records, as, for example, those buried in papers dealing with other phases of cockroach biology. We hope that such inadvertent omissions will not seriously impair the usefulness of this compilation. Whatever its defects, this review should be a unified source of information for all who are interested in the biotic associates of cockroaches.

In addition to previously published information, this monograph also contains original records and observations on the associations of cockroaches that are reported here for the first time. Although some of the observations were made by us, others were made by colleagues who have graciously made their knowledge available to us in private communications.

HISTORICAL

Chopard (1938) in his book _La Biologie des Orthoptères_ reviewed much of the literature on cockroaches, but of the many biotic associations that exist he discussed only the commensal cockroaches, gregariousness, and familial associations. Asano (1937), who reviewed the natural enemies of cockroaches, mentioned about 10 groups of animals that attack cockroaches. Thompson (1951) in his _Parasite Host Catalogue_, which was based mainly on papers abstracted or noted in the Review of Applied Entomology, listed only 19 insect parasites of cockroaches. Eighteen of these were Hymenoptera which attack only cockroach eggs; the single dipteron listed (_Sarcophaga lambens_ Wiedemann, supposedly parasitic on _Pycnoscelus surinamensis_) is not a parasite in this case, but deposits its eggs on the dead insects (see p. 229). Cameron (1955) listed as parasites and predators of the cockroach 24 species of hymenopterous egg parasites, 7 species of _Ampulex_ which hunt nymphs and adults, 17 Protozoa, 13 nematodes, 5 bacteria, 2 mites, and a few other miscellaneous predators. In his classified list of the protozoan parasites of the Orthoptera of the world, Semans (1943) listed about 26 species from cockroaches. Linstow (1878, 1889) recorded 14 species of helminths from cockroaches. Van Zwaluwenburg (1928) listed 33 names of roundworms which are commensals or secondary parasites of cockroaches, but some of these names are synonyms. La Rivers (1949) extended this list with 13 additional species. Chitwood (1932) recognized 24 species of nematodes which are primary parasites (probably commensals) of blattids. Steinhaus (1946) gave many instances of biological relationships between cockroaches and bacteria, fungi, and yeasts, but the cockroaches were not discussed as an entity and the information is scattered throughout the book.

In surveying the literature on this subject we have collected a far more extensive list of animals and plants associated with cockroaches than one might have expected from an examination of any one of the previous papers on this subject. In our review of the medically important organisms associated with the Blattaria, we pointed out that in addition to many experimental associations cockroaches have been found to harbor, naturally, 4 strains of poliomyelitis virus, about 40 species of pathogenic bacteria, the eggs of 7 species of pathogenic helminths, and to serve as intermediate hosts of 12 other species of helminths pathogenic for vertebrates; cockroaches have also been found to carry, on occasion, 3 species of Protozoa that are pathogenic to man and 2 species of fungi which are sometimes found associated with pathological conditions.

In addition to the above organisms of medical importance, we have compiled records of other organisms, nonpathogenic to vertebrates, which are naturally associated in some way with cockroaches. None of the following numbers can be considered absolute because some names may be synonyms. However, we believe that these figures are very close to the actual numbers of species that have been isolated because we have attempted to refer all obvious synonyms to the currently accepted name for each organism. On this basis there are about 45 species of bacteria, 40 fungi, 6 yeasts, 90 Protozoa, and 45 helminths that have been found associated naturally with cockroaches. Of the arthropods there are about 2 species of scorpions, 4 spiders, 15 mites, 4 centipedes, and 90 insects. Of vertebrates there are 4 species of fish, 16 amphibians, 12 reptiles, 20 birds, and 27 mammals. Besides these there are many records of experimental associations that have been contrived in the laboratory.

Some idea of the increase in our knowledge of the biotic associations of cockroaches, during the last 70 years, may be gathered from a comparison of the above figures with those of Miall and Denny (1886) who presented "...a long list of parasites which infest the Cockroach." This list included 2 bacteria, 6 Protozoa (some of the names are synonyms), 7 nematodes (some of these names are also synonyms), 1 mite, 1 wasp, and 1 beetle. In addition, they mentioned as other foes of the cockroach: monkeys, hedgehogs, polecats, cats, rats, birds, chameleons, and frogs.

METHODS

We have listed the organisms known to be associated with cockroaches systematically by phylum, class, order, and family. Within each family the organisms are listed alphabetically by genus and species. Under each organism the associated cockroaches are listed as natural or experimental hosts, vectors, or prey. Identified cockroaches are listed by the currently accepted name. Unidentified cockroaches are indicated by the word "Cockroaches." The name of each cockroach is followed by the country in which the observation was made, the authority for the record, and with a few exceptions[3] pertinent biological information, where this is known. Question marks following the names of organisms or countries indicate tentative or questionable identifications.

Records of predators capturing and feeding on cockroaches in zoos and on shipboard we consider natural, even though it is very likely that these particular predators would not normally have access to this prey in nature.

Experimental prey are cockroaches that were fed to predators in the laboratory. Although these predators may have little, if any, access to these cockroaches in nature, we have included such records to indicate the relative acceptability of cockroaches as food by a wide variety of animals.

Records of presumed or known cockroach associates that give no information about an associated cockroach are not included in this review, even though certain of these (e.g., species of _Ampulex_, _Evania_, _Podium_) probably prey upon or parasitize cockroaches exclusively.

The validity of a host-parasite or predator-prey record is dependent upon the accuracy and knowledge of the observer. In assembling these records we have had to accept, in most instances, the identifications of species made by the original authors. However, as a result of our studies on the biology of various species of cockroaches, including some work on their hymenopterous parasites, we have questioned certain records in the literature. Other dubious records which have been perpetuated from one publication to the next, but which apparently were not based on fact, have also been questioned or have been clarified with the aid of specialists in particular groups.

Because the records cover a period of many years, the names of many of the organisms as well as the names of some of the cockroaches have been changed. Although it would have been comparatively simple to list the names as they appeared in the original references, this would have resulted in misleading redundancy with the same organism being catalogued under several synonyms. We have attempted to list each organism by its currently accepted name. However, no attempt was made to prepare complete taxonomic synonymies; the only synonyms given are those that identify the organisms by the names used by the authors of the papers cited. The synonyms under which the cockroaches may have been cited originally are listed in section II. The synonyms of associated organisms are listed with each organism. Although authorities for the name changes of the cockroaches are given, these workers are not necessarily those who were initially responsible for the synonymies. Various sections have been checked by specialists in the particular groups. Although we have accepted name changes suggested by these reviewers, we assume full responsibility for the names.

FUTURE WORK

After having examined thousands of references on cockroaches, we are impressed by how little is known about the biology of most species. As a conservative estimate there are 3,500 described species of Blattaria (J. W. H. Rehn, 1951). In our literature survey we found records of biotic associations for about 400 species. Unfortunately, many of these records contain only a sentence or two of biological information. Our detailed knowledge of cockroaches is based on studies of the few domiciliary pests that man attempts to eradicate. Comparable studies of the bionomics of the less-well-known species should add much valuable information to our knowledge of this ancient group.

Our understanding of most predator-prey and parasite-host relationships has barely progressed beyond the taxonomic stage. The total effect of predators and parasites in limiting natural populations of cockroaches remains to be determined. It is still not known how, for example, predatory or parasitic wasps select specific cockroaches from among all other insects. Secretions produced by certain cockroaches (e.g., 2-hexenal by _Eurycotis floridana_) will ward off certain predators. The identities and biological activities of most cockroach secretions are unknown, but the use of protective chemicals against predators may be widespread among cockroaches. If so, how effective are these repellents in protecting the individual or the species? It is not known whether cockroaches are protected by apparent mimetic resemblances to other arthropods. There is no experimental proof that insect parasites can successfully attack the eggs of cockroaches that incubate their eggs while they are being carried by the female.

It is conceivable that biological control of cockroaches might be achieved in limited areas such as man-made structures or sewers, but this possibility has not been thoroughly explored. It would be informative to know what effects, if any, organisms such as bacteria, Protozoa (e.g., gregarines), intestinal nematodes, or other helminths have on cockroaches. Possibly pathogenic microorganisms can be used for biological control of cockroaches; this approach seems to have been little explored.

Associations of colonial cockroaches (e.g., _Cryptocercus_ spp.) may be truly familial or they may merely result from gregariousness. Newly hatched nymphs of species that carry their oöthecae until the eggs hatch cluster near the mother. This may be a response to the mother as such, a search for shelter beneath the nearest object (thigmotaxis? or negative phototaxis?), or there may well be yet another explanation. Tepper in 1893 stated that the native cockroaches of Australia are almost wholly carnivorous; little supporting evidence for this claim has been brought forward since that time. The apparent supersedure of one species of domiciliary cockroach by another may result from antagonism between different species, or it may result from more rapid breeding and more effective utilization of available food and space; but which? Several species of cockroaches are frequently found associated with certain plants (e.g., bromeliads and bananas); the ecological relations in these associations remain to be determined. Many of the obscure associations between cockroaches and other insects, spiders, birds, and burrowing animals have never been adequately defined. The factors influencing cannibalism have never been thoroughly investigated experimentally. These are only a few ideas for future work that have occurred to us during the preparation of this review. We hope that these suggestions as well as other questions that may occur to readers will stimulate further research in areas where it is obviously needed.

ILLUSTRATIONS

Unless otherwise credited, the illustrations were prepared from photographs taken by the authors. Except where otherwise stated, all photographs were taken of unposed living specimens.

II. SPECIES OF COCKROACHES

The cockroaches referred to in this paper are listed below. The currently accepted name for each species is given alphabetically by genus and species irrespective of its taxonomic affinities. Synonyms used by certain authors whose work we have quoted are given in brackets under the respective species; the synonymy is supported by the reference citation that follows each synonym. References to illustrations of certain species (e.g., _Blaberus craniifer_) that appear in the paper follow the names of the describers.

_Agis orientalis_ Chopard

_Aglaopteryx absimilis_ Gurney _diaphana_ (Fabricius) [_Ceratinoptera
diaphana_ Fabricius; Rehn and Hebard (1927)]
_facies_ (Walker) [_Aglaopteryx devia_ Rehn; Princis (1929).
_A. diaphana_ (Fabricius) in records from Puerto Rico only;
Rehn (1932b); Gurney (1937)]
_gemma_ Hebard [In Florida records = _Ceratinoptera diaphana_ R. and
H.; Hebard (1917)]
_vegeta_ Rehn
_ypsilon_ Princis

_Allacta similis_ (Saussure) [_Phyllodromia obtusata_ Brunner;
Zimmerman (1948)]

_Alluaudellina cavernicola_ (Shelford) [_Alluaudella cavernicola_
Shelford; Chopard (1932)]

_Amazonina emarginata_ Princis

_Anaplecta asema_ Hebard
_azteca_ Saussure
_decipiens_ Saussure and Zehntner
_fallax_ Saussure
_hemiscotia_ Hebard
_lateralis_ Burmeister
_mexicana_ Saussure

_Aneurina tahuata_ Hebard
_viridis_ Hebard

_Apotrogia angolensis_ Kirby [_Acanthogyna deplanata_ Chopard;
Princis (1957)]

_Aptera fusca_ (Thunberg) [_Aptera cingulata_ (Burmeister);
Gurney (personal communication, 1957)]

_Apteroblatta perplexa_ Shelford

_Archiblatta hoevenii_ Vollenhoven

_Archimandrita marmorata_ (Stoll)
_tessellata_ Rehn

_Arenivaga apacha_ (Saussure)
_bolliana_ (Saussure)
_erratica_ (Rehn)
_floridensis_ Caudell
_grata_ Hebard
_roseni_ (Brancsik) [_Heterogamodes roseni_; Bei-Bienko (1950).
_"Polygamia" roseni_ is undoubtedly an erroneous citation of
_Polyphaga roseni_, as there is no genus _Polygamia_ (Gurney,
personal communication, 1957)].
_tonkawa_ Hebard

_Aristiger histrio_ (Burmeister) [_Plumiger histrio_ (Burm.);
Bruijning (1948). _Hemithyrsocera histrio_ Burm.; Hebard (1929)]

_Aspiduchus boriquen_ J. W. H. Rehn [In Puerto Rico records =
_Aspiduchus deplanatus_ R. and H.; Rehn, J. W. H. (1951a)]
_cavernicola_ J. W. H. Rehn
_deplanatus_ (Saussure)

_Attaphila aptera_ Bolívar
_bergi_ Bolívar
_flava_ Gurney
_fungicola_ Wheeler
_schuppi_ Bolívar
_sexdentis_ Bolívar

_Atticola mortoni_ Bolívar

_Audreia bromeliadarum_ Caudell
_jamaicana_ Rehn and Hebard

_Balta godeffroyi_ (Shelford)
_patula_ (Walker)
_platysoma_ (Walker) [_Temnopteryx platysoma_ (Walker); Hebard
(1943)]
_quadricaudata_ Hebard
_scripta_ (Shelford)
_torresiana_ Hebard
_verticalis_ Hebard

_Bantua stigmosa_ (Krauss) [_Derocalymma stigmosa_ Krauss; Princis
(1957)]

_Blaberus atropos_ (Stoll) [_Blabera fusca_ Brunner; Hebard (1917)]
_boliviensis_ Princis
_craniifer_ Burmeister (pls. 1, 2)
_discoidalis_ Serville [_Blaberus cubensis_ Saussure; Hebard
(1916)]
_giganteus_ (Linnaeus) (pl. 3)

_Blaptica dubia_ (Serville) [_Blaberus clarazianus_ Saussure; Rehn,
J. W. H. (1951)]

_Blatta orientalis_ Linnaeus (pl. 4) [_Periplaneta orientalis_;
Hebard (1917)]
(_Shelfordella_) _lateralis_ (Walker) [_Shelfordella tartara_
(Saussure); Princis (1957). _Periplaneta tartara_ Saussure;
Bei-Bienko (1950)]

_Blattella germanica_ (Linnaeus) (pls. 5, A, B; 31, F)
[_Blatella germanica_; Gurney (1952). _Phyllodromia germanica_;
Hebard (1917). _Ectobius germanicus_; Gurney (personal
communication, 1957)]
_humbertiana_ (Saussure) [_Blatta humbertiana_; _Phyllodromia
humbertiana_; Hebard (1929)]
_lituricollis_ (Walker) (fig. 7, A) [_Blattella bisignata_
(Brunner); Bei-Bienko (1950)]
_schubotzi_ Shelford
_vaga_ Hebard (pl. 5, C, D)

_Buboblatta armata_ (Caudell) [_Latindia armata_ Caudell; Hebard
(1920)]

_Byrsotria cabrerae_ Rehn and Hebard
_fumigata_ (Guérin) (pl. 6)

_Cahita borero_ Rehn
_nahua_ (Saussure)

_Capucinella delicatula_ Hebard

_Cariblatta antiguensis_ (Saussure and Zehntner)
_cuprea_ Hebard
_delicatula_ (Guérin) [_Blattella delicatula_ Guérin; _Cariblatta
punctulata_ (Beauvois); Rehn and Hebard (1927)]
_hylaea_ Rehn
_imitans_ Hebard
_insularis_ (Walker)
_landalei_ Rehn and Hebard
_lutea lutea_ (Saussure and Zehntner)
_lutea minima_ Hebard (pl. 7, A, B)
_nebulicola_ Rehn and Hebard
_orestera_ Rehn and Hebard
_punctipennis_ Hebard
_reticulosa_ (Walker)
_stenophrys_ Rehn and Hebard

_Cariblattoides instigator_ Rehn and Hebard
_suave_ Rehn and Hebard

_Ceratinoptera picta_ Brunner

_Chorisoneura barbadensis_ Rehn and Hebard
_flavipennis_ Saussure and Zehntner
_formosella_ Rehn and Hebard
_parishi_ Rehn
_specilliger_ Hebard
_texensis_ Saussure and Zehntner [_Chorisoneura plocea_ Rehn; Rehn
and Hebard (1916)]
_translucida_ (Saussure)

_Choristima_ sp.

_Choristimodes_ sp.

_Chromatonotus infuscatus_ (Brunner)
_notatus_ (Brunner)

_Compsodes schwarzi_ (Caudell)

_Comptolampra liturata_ (Serville) [_Compsolampra liturata_;
_Comptolampra_ is the original spelling, which is followed by Dr.
K. Princis, according to Gurney (personal communication, 1959)]

_Cosmozosteria lateralis_ (Walker)

_Cryptocercus punctulatus_ Scudder (pl. 8, A)
_relictus_ Bei-Bienko

_Cutilia nitida_ (Brunner)
_soror_ (Brunner)
sp. near _sedilloti_ (Bolívar) (pl. 9) [Determined by Dr. A. B.
Gurney from photographs.]

_Cyrtotria capucina_ (Gerstaecker)

_Dendroblatta sobrina_ Rehn

_Derocalymma cruralis_ (Stål) [_Homalodemas cruralis_ (Stål); Gurney
(personal communication, 1957)]
_lampyrina_ Gerstaecker
_porcellio_ Gerstaecker

_Deropeltis autraniana_ Saussure
_erythropeza_ Adelung
_melanophila_ (Walker)
_nigrita_ Saussure

_Diploptera punctata_ (Eschscholtz) (pls. 10, 36) [_Diploptera
dytiscoides_ (Serville); Princis (1950). _Eleutheroda
dytiscoides_ (Serville); Zimmerman (1948)]

_Dryadoblatta scotti_ (Shelford) [_Homalopteryx scotti_ Shelford;
Rehn (1930)]

_Ectobius africanus_ Saussure
_albicinctus_ (Brunner)
_duskei_ Adelung
_lapponicus_ (Linnaeus) [_Ectobius perspicillaris_ Herbst, as used
by Lucas (1920); Blair (1934)]
_lucidus_ Hgb.
_nicaeensis_ (Brisout)
_pallidus_ (Olivier) (pls. 7, C; 29, A) [_Ectobius lividus_
(Fabricius); _Ectobius livens_ (Turton); Kevan (1952); Princis
(_in_ Roth and Willis, 1957)]
_panzeri_ Stephens [_Ectobius ericetorum_ (Wesmaël); Ramme (1923)]
_panzeri_ var. _nigripes_ Stephens
_semenovi_ Bei-Bienko
_sylvester_ (Poda) [_Ectobius sylvestris_ (Poda); Ramme (1951)]
_tadzihicus_ Bei-Bienko
_vittiventer_ (Costa) [_Ectobius vittiventris_ (Costa); Ramme
(1951)]

_Ellipsidion_ Saussure [_Apolyta_ Brunner; Hebard (1943)]
_affine_ Hebard
_australe_ Saussure [_Ellipsidion pellucidum_ (Brunner); Hebard
(1943)]
_bicolor_ (Tepper)
_simulans_ Hebard
_variegatum_ (Fabricius) [_Ellipsidion aurantium_ Saussure; Hebard
(1943)]

_Epilampra abdomen-nigrum_ (De Geer)
_annandalei_ Shelford
_azteca_ Saussure
_conferta_ Walker
_conspersa_ Burmeister
_grisea_ (De Geer)
_maya_ Rehn
_mexicana_ Saussure
_mona_ Rehn and Hebard
_notabilis_ Walker
_sodalis_ Walker
_tainana_ Rehn and Hebard
_wheeleri_ Rehn
sp. (fig. 7, B, C)

_Eremoblatta subdiaphana_ (Scudder)

_Ergaula capensis_ (Saussure) [_Dyscologamia capensis_ Saussure;
_Dyscologamia wollastoni_ Kirby; Princis (1957)]
_scarabaeoides_ Walker [_Dyscologamia piolosa_ (Walker); Princis
(1957). _Parapolyphaga erectipilis_ Chopard; Princis (1950).
_Dyscologamia chopardi_ Hanitsch; Bruijning (1948).
_Miroblatta silphoides_ Chopard; Hebard (1929)].

_Escala_ sp.

_Euandroblatta palpalis_ Chopard

_Eublaberus posticus_ (Erichson)

_Eudromiella bicolorata_ Hebard
_calcarata_ Bei-Bienko

_Euphyllodromia angustata_ (Latreille)
_liturifera_ [_Euphyllodromia decastigmata_ Hebard; Princis (1959)]

_Eurycotis bananae_ Bei-Bienko
_biolleyi_ Rehn [_Eurycotis carbonaria_ Biolley; Rehn (1918)]
_caraibea_ (Bolívar)
_decipiens_ (Kirby)
_dimidiata_ (Bolívar)
_ferrum-equinum_ Rehn and Hebard
_floridana_ (Walker) (pl. II) [_Platyzosteria ingens_ Scudder;
_Platyzosteria sabalianus_ Scudder and hence, by inference,
_Eurycotis sabalianus_ (Scudder); Hebard (1917)]
_galeoides_ Rehn and Hebard
_improcera_ Rehn
_kevani_ Princis
_lixa_ Rehn
_manni_ Rehn
_opaca_ (Brunner)

_Euthlastoblatta abortiva_ (Caudell)

_Euthyrrhapha nigra_ Chopard
_pacifica_ Coquebert

_Geoscapheus robustus_ Tepper

_Graptoblatta notulata_ (Stål) [_Blatta notulata_ Stål; Hebard (1929).
_Phyllodromia hieroglyphica_ Brunner; Kirby (1904)]

_Gromphadorhina laevigata_ S. and Z.
_portentosa_ (Schaum) (pl. 12, A, B)

_Gyna kazungulana_ Giglio-Tos
_maculipennis_ (Schaum) [_Gyna vetula_ Brunner; Shelford (1909b)]
_tristis_ Hanitsch

_Hebardina concinna_ (Haan) [_Blatta concinna_ Haan;
_Blattina concinna_ (Haan); Bei-Bienko (1950)]

_Hemiblabera brunneri_ (Saussure)

_Henicotyle antillarum_ (Brunner)

_Heterogamodes krügeri_ (Salfi)
_rugosa_ (Schulthess)

_Holocompsa azteca_ (Saussure)
_cyanea_ (Burmeister)
_fulva_ (Burmeister)
_metallica_ Rehn and Hebard
_nitidula_ (Fabricius)
_zapoteca_ Saussure

_Hololampra bivittata_ (Brullé)
_chavesi_ (Bolívar)
_maculata_ (Schreber) [_Aphlebia maculata_ Schreber; Harz (1957);
Gurney (personal communication, 1959)]
_marginata_ (Schreber)
_punctata_ (Charpentier) [_Aphlebia punctata_ Charpentier; Ramme
(1951)]

_Hololeptoblatta_ sp.

_Homalopteryx laminata_ Brunner

_Hoplosphoropyga babaulti_ Chopard

_Hormetica apolinari_ Hebard
_laevigata_ Burmeister
_ventralis_ Burmeister

_Ignabolivaria bilobata_ Chopard

_Ischnoptera deropeltiformis_ (Brunner) (pl. 12A)
[_Temnopteryx deropeltiformis_ Brunner; Hebard (1917)]
_panamae_ Hebard
_podoces_ Rehn and Hebard
_rufa occidentalis_ Saussure
_rufa rufa_ (De Geer)
_schenklingi_ Karney

_Karnyia discoidalis_ (Brunner)

_Kuchinga hemerobina_ (Gerstaecker) [_Phyllodromia hemerobina_
Gerstaecker; Rehn (1932)]
_remota_ Hebard

_Lamproblatta albipalpus_ Hebard
_meridionalis_ (Brunner)

_Latiblattella chichimeca_ (Saussure and Zehntner)
[_Blattella chichimeca_ S. and Z.; Hebard (1932)]
_lucifrons_ Hebard
_rehni_ Hebard
_vitrea_ (Brunner)
_zapoteca_ (Saussure)

_Leucophaea maderae_ (Fabricius) (pl. 13) [_Rhyparobia maderae_;
Hebard (1917). _Panchlora maderae_; Kirby (1904). Very probably
_"Blaberus" maderae_ is a careless reference to this species;
Gurney (personal communication, 1957)]

_Leurolestes pallidus_ (Brunner)

_Litopeltis biolleyi_ (Saussure)
_bispinosa_ (Saussure) [_Audreia marginata Caudell_; Hebard (1920)]
_deianira_ Rehn
_musarum_ Rehn

_Lobolampra subaptera_ Rambur

_Loboptera decipiens_ (Germar)
_thaxteri_ Hebard

_Lobopterella dimidiatipes_ (Bolívar) [_Loboptera dimidiatipes_
(Bolívar); Princis (1957a). _Loboptera sakalava_ (Saussure);
Hebard (1933a). _Loboptera extranea_ Perkins; Hebard (1922).
Princis (1957a) in erecting _Lobopterella_ pointed out that only
the nontypical variety of _sakalava_ is identical with
_dimidiatipes_.]

_Lophoblatta arawaka_ Hebard

_Macropanesthia rhinocerus_ Saussure

_Mareta acutiventris_ Chopard

_Maretina uahuka_ Hebard

_Megaloblatta blaberoides_ (Walker) [_Megaloblatta rufipes_ Dohrn;
Hebard (1920)]

_Megamareta verticalis_ Hebard

_Melanosilpha capensis_ Saussure and Zehntner

_Methana canae_ Pope
_curvigera_ (Walker)
_marginalis_ (Saussure)

_Moluchia (?) dahli_ Princis

_Monastria biguttata_ (Thunberg)

_Muzoa madida_ Rehn

_Myrmeblattina longipes_ (Chopard)

_Myrmecoblatta rehni_ Mann
_wheeleri_ Hebard

_Namablatta bitaeniata_ (Stål)

_Nauclidas nigra_ (Brunner) [_Poroblatta nigra_ Brunner; Rehn (1930)]

_Nauphoeta cinerea_ (Olivier) (pl. 14) [_Nauphoeta bivittata_
Burmeister; Zimmerman (1948)]
_flexivitta_ (Walker) [_Nauphoeta brazzae_ (Bolívar); Rehn (1937)]
_punctipennis_ Chopard

_Nelipophygus ramsdeni_ Rehn and Hebard

_Neoblattella brunneriana_ (Saussure) [_Blattella brunneriana_; Gurney
(personal communication, 1959)]
_carcinus_ Rehn and Hebard
_celeripes_ Rehn and Hebard
_detersa_ (Walker)
_dryas_ Rehn and Hebard
_eurydice_ Rehn and Hebard
_fratercula_ Hebard
_fraterna_ (Saussure and Zehntner)
_grossbecki_ Rehn and Hebard
_laodamia_ Rehn and Hebard
_nahua_ (Saussure) [_Blattella nahua_ Saussure and Zehntner of
Caudell (1914); Hebard (1920)]
_proserpina_ Rehn and Hebard
_semota_ Rehn and Hebard
_tridens_ Rehn and Hebard
_vatia_ Rehn and Hebard

_Neostylopyga rhombifolia_ (Stoll) (pl. 15) [_Dorylaea rhombifolia_;
Rehn (personal communication, 1956)]

_Nesomylacris cubensis_ Rehn and Hebard
_relica_ Rehn and Hebard

_Nocticola bolivari_ Chopard
_caeca_ Bolívar
_decaryi_ Chopard
_simoni_ Bolívar
_sinensis_ Silvestri
_termitophila_ Silvestri

_Nothoblatta wasmanni_ (Bolívar)

_Notolampra antillarum_ Shelford

_Nyctibora azteca_ Saussure and Zehntner
_brunnea_ (Thunberg)
_laevigata_ (Beauvois)
_lutzi_ Rehn and Hebard
_mexicana_ Saussure
_noctivaga_ Rehn
_obscura_ Saussure
_sericea_ Burmeister
_stygia_ Walker
_tomentosa_ Serville [_Nyctibora latipennis_ Burmeister; Hebard
(1917, p. 263)]

_Oniscosoma granicollis_ (Saussure)

_Opisthoplatia maculata_ Shiraki
_orientalis_ (Burmeister)

_Oulopteryx meliponarum_ Hebard

_Oxyhaloa buprestoides_ (Saussure)
_deusta_ (Thunberg)

_Panchlora antillarum_ Saussure
_exoleta_ Burmeister
_fraterna_ Saussure and Zehntner
_nivea_ (Linnaeus) (pl. 16) [_Panchlora cubensis_ Saussure; Gurney
(1955). _Pycnosceloides aporus_ Hebard; Hebard (1921c)]
_peruana_ Saussure
_sagax_ Rehn and Hebard
_virescens_ (Thunberg)

_Panesthia angustipennis_ (Illiger) [_Panesthia javanica_ Serville;
Hebard (1929)]
_australis_ Brunner (pl. 8, B)
_laevicollis_ Saussure
_lobipennis_ Brunner
_spadica_ (Shiraki)

_Parahormetica bilobata_ (Saussure)

_Parcoblatta americana_ (Scudder)
_bolliana_ (Saussure and Zehntner) [_Kakerlac schaefferi_ Rehn;
Hebard (1917)]
_caudelli_ Hebard [[F][F] of _Ischnoptera insolita_ R. and H.;
_Ischnoptera uhleriana fulvescens_ S. and Z. (in part); Hebard
(1917)]
_desertae_ (Rehn and Hebard) [[M][M] of _Ischnoptera insolita_ R.
and H.; Hebard (1917)]
_divisa_ (Saussure and Zehntner) [_Ischnoptera divisa_ S. and Z.;
Hebard (1917)]
_fulvescens_ (Saussure and Zehntner)
[_Ischnoptera uhleriana fulvescens_ S. and Z. (in part); Hebard
(1917)]
_lata_ (Brunner) [_Ischnoptera couloniana_ R. and H. (not Saussure);
_Ischnoptera major_ R. and H. (not S. and Z.); Hebard (1917)]
_notha_ Rehn and Hebard
_pensylvanica_ (De Geer) (pl. 17, A) [_Ischnoptera pennsylvanica_
Saussure; Hebard (1917)]
_uhleriana_ (Saussure) (pl. 18) [_Ischnoptera uhleriana_ Saussure;
Hebard (1917)]
_virginica_ (Brunner) (pls. 17, B; 27, A; 33, C; fig. 6)
[_Ischnoptera borealis_ Brunner; Hebard (1917)]
_zebra_ Hebard

_Pelmatosilpha coriacea_ Rehn
_kevani_ Princis
_marginalis_ Brunner
_purpurascens_ (Kirby)
_rotundata_ Scudder
_vagabunda_ Princis

_Periplaneta americana_ (Linnaeus) (pls. 19, 35)
[_Stylopyga americana_; _Blatta americana_ L.; Hebard (1917)]
_australasiae_ (Fabricius) (pls. 20, 32)
_brunnea_ Burmeister (pl. 21)
_cavernicola_ Chopard
_fuliginosa_ (Serville) (pl. 22)
_ignota_ Shaw
_lata_ (Herbst)

_Perisphaerus armadillo_ Serville
_glomeriformis_ (Lucas)

_Phaetalia pallida_ (Brunner)

_Phidon (?) dubius_ Princis

_Phlebonotus pallens_ (Serville)

_Pholadoblatta inusitata_ (Rehn)

_Phorticolea boliviae_ Caudell
_testacea_ Bolívar

_"Phyllodromia" treitliana_ Werner

_Phyllodromica brevipennis_ (Fischer)
_graeca_ (Brunner)
_irinae_ (Bei-Bienko)
_maculata_ (Schreber)
_megerlei_ (Fieber)
_polita_ (Krauss)
_pygmaea_ (Bei-Bienko)
_tartara_ (Saussure)
_tartara nigrescens_ Bei-Bienko

_Platyzosteria analis_ (Saussure) [_Polyzosteria analis_ Saussure;
Kirby (1904)]
_armata_ Tepper
_bifida_ (Saussure)
_castanea_ (Brunner)
_novae seelandiae_ (Brunner) (pl. 23) [_Periplaneta fortipes_
Walker; Shelford (1912); _Platyzosteria novae-zealandiae_]
_scabra_ (Brunner)

_Plectoptera dorsalis_ (Burmeister)
_infulata_ (Rehn and Hebard)
_lacerna_ Rehn and Hebard
_perscita_ Rehn and Hebard
_poeyi_ (Saussure) [_Plectoptera floridana_ Hebard; Rehn and Hebard
(1927)]
_porcellana_ (Saussure)
_pygmaea_ (Saussure)
_rhabdota_ (Rehn and Hebard)
_vermiculata_ Rehn and Hebard

_Polyphaga aegyptiaca_ (Linnaeus) [_Blatta aegyptiaca_ L.; Bei-Bienko
(1950). _Heterogamia aegyptiaca_ (L.); Gurney (personal
communication, 1957). _"Polygamia" aegyptiaca_; according to
Gurney (p. c.), there is no genus _Polygamia_ and almost surely
the reference is to _Polyphaga aegyptiaca_.]
_indica_ Walker [_Polyphaga pellucida_ (Redtenbacher); Princis
(1957)]
_saussurei_ (Dohrn)

_Polyzosteria limbata_ Burmeister
_melanaria_ (Erichson)

_Pseudoderopeltis aethiopica_ (Saussure) [_Blatta aethiopica_
Saussure; Gurney (personal communication, 1957)]

_Pseudomops cincta_ (Burmeister) [_Thyrsocera cincta_ Scudder; Hebard
(1917)]
_laticornis_ Perty
_septentrionalis_ Hebard

_Pseudophoraspis nebulosa_ (Burmeister)

_Pycnoscelus niger_ (Brunner)
_striatus_ (Kirby) [_Leucophaea striata_ Kirby; Gurney (personal
communication, 1957)]
_surinamensis_ (Linnaeus) (pl. 24) [_Leucophaea surinamensis_ (L.);
Hebard (1917). _Blatta melanocephala_ Stoll; Kirby (1904)]

_Rhicnoda natatrix_ Shelford

_Rhytidometopum dissimile_ Princis

_Riatia fulgida_ (Saussure) [_Lissoblatta fulgida_ (Saussure); Gurney
(personal communication, 1959)]
_orientis_ Hebard

_Robshelfordia circumducta_ (Walker) [_Escala circumducta_ (Walker);
Gurney (personal communication, 1957)]
_longiuscula_ (Walker) [_Escala longiuscula_ (Walker); Gurney
(personal communication, 1957)]

_Salganea morio_ (Burmeister)

_Sibylloblatta panesthoides_ (Walker)

_Simblerastes jamaicanus_ Rehn and Hebard

_Spelaeoblatta gestroi_ Bolívar

_Sphecophila polybiarum_ Shelford
_ravana_ Fernando
_termitium_ Shelford

_Steleopyga (?) sinensis_ Walker [Dr. Gurney (personal communication,
1957) could not find a reference to this species. Walker
described species named _sinensis_ in three different genera of
cockroaches, and it is uncertain which one this combination
represents.]

_Stictolampra buqueti concinula_ (Walker)

_Styphon bakeri_ Rehn

_Supella hottentotta_ (Saussure)
_supellectilium_ (Serville) (pls. 25; 30, B-E; 31, A-E)
[_Phyllodromia supellectilium_ (Serv.); Bei-Bienko (1950)]

_Symploce breviramis_ (Hanitsch)
_cavernicola_ (Shelford) [_Ischnoptera cavernicola_ (Shelford);
_Phyllodromia nigrocincta_ Chopard; Hebard (1929)]
_curta_ Hanitsch
_flagellata_ Hebard
_hospes_ (Perkins) [_Symploce lita_ Hebard; Hebard (1922)]
_jamaicana_ (Rehn)
_kevani_ Chopard
_parenthesis_ (Gerstaecker) [_Phyllodromia parenthesis_
Gerstaecker; Rehn (1932)]
_remyi_ (Hanitsch) [_Ischnoptera remyi_ Hanitsch; Chopard (1938)]
_ruficollis_ (Fabricius) [_Symploce bilabiata_ Rehn and Hebard;
Princis (1949a)]

_Tartaroblatta karatavica_ Bei-Bienko

_Temnopteryx obliquetruncata_ Chopard
_phalerata_ (Saussure)

_Theganopteryx straminea_ Chopard

_Therea nuptialis_ (Gerstaecker) [_Corydia nuptialis_ Gerstaecker;
Princis (1950)]

_Tivia australica_ Princis
_brunnea_ (Chopard)
_fulva_ (Burmeister)
_macracantha_ Chopard
_obscura_ (Chopard)

_Typhloblatta caeca_ (Chopard) [_Spelaeoblatta caeca_ Chopard;
Chopard (1924b)]

_Typhloblattodes madecassus_ Chopard

_Xestoblatta festae_ (Griffini)
_immaculata_ Hebard

III. ECOLOGICAL RELATIONSHIPS

The ecology of extinct cockroaches is necessarily a highly speculative subject. From the coexistence of fossil cockroaches and fossil plants in the same geological stratum, one might conclude that there had been intimate associations between them during prehistoric life. Heer (1864) and Goldenberg (1877) suggested that Carboniferous cockroaches fed on the plants with which they have been found as fossils. Scudder (1879) concurred with this hypothesis. However, Bolton (1911), remarking on the noticeable associations of blattoid wings with vegetable remains, suggested that the cockroaches may have been partly carnivorous, feeding on the snails _Spirorbis pusillus_, which were attached to the leaves of _Cordaites_. Yet the proximity of fossil insects and plants in the same geological formation is hardly proof of a similar association during life. In fact, Sellards (1903), Bolton (1921), and Laurentiaux (1951) have all pointed out that the cockroach remains, particularly the more resistant wings, may have been washed into streams by heavy rains and transported with drifting plant material to places where permanent deposits were accumulating.

Some species of fossil cockroaches have long, well-developed ovipositors, very unlike present-day cockroaches whose ovipositors are small and nonprotruding. Brongniart (1889) and Zalesskii (1939, 1953) have suggested that certain Permian and Carboniferous cockroaches with long ovipositors may have inserted their eggs singly into trees and other plants, rather than protecting the eggs with an oötheca. However, Laurentiaux (1951), although conceding the possibility of egg laying in vegetable material, suggested that oviposition into the earth is more probable because of the unbending nature of the ovipositor.

Although the ecological associations of modern cockroaches should be well known from direct observation, actually most species are still little more than names on museum specimens, and our knowledge of them is fragmentary. All too frequently ecological observations have been only incidental to taxonomic or faunistic studies; yet the biological information that is contained in such papers is all that we know of many species. For this reason we have cited these observations in some detail, especially when they were brief; longer accounts of cockroach bionomics, of necessity, have been abstracted.

Very few exclusively ecological studies of insects have included cockroaches. The native woodroaches (_Parcoblatta pensylvanica_, _P. uhleriana_, and _P. virginica_) of the northern United States were included in ecological studies of the Orthoptera by Hubbell (1922), Strohecker (1937), and Cantrall (1943). Fifteen species of cockroaches were included in an ecological study of the Orthoptera of northern Florida by Friauf (1953). The original papers should be consulted for detailed descriptions of the habitats and accounts of the associated plants and other Orthoptera.

In this chapter the cockroaches are grouped into those that have been found in man-made structures and those that occur in other habitats. Certain species may appear in several categories because they live both indoors and out. The structural pests are divided into cockroaches that occur in land-based structures, those on ships, and those in aircraft. The nonstructural cockroaches are divided into those that occur in quite specific habitats (caves, water, and deserts) and those that occur generally out of doors. Nests of various arthropods serve as microhabitats of commensal cockroaches; these latter associations are discussed on pages 310-318.

In this chapter our discussion is limited to the physical environment and specific habitats of cockroaches, and only very general references are made to associated organisms. The relationships of cockroaches to the biota are examined in detail in subsequent chapters. To show the full extent of the associations, the associates, from bacteroids to vertebrates, are arranged phyletically. These associate-centered classifications serve admirably to relate various species of cockroaches within common bounds, but fail to give an integrated account of the total biotic relationships in the ecology of each species. Although physically separated in this monograph, the many associates of each species of cockroach should all be considered in appraising the ecology of that species. To assist the reader to achieve this end, we have included a checklist (p. 290) which serves as a convenient index to certain organisms associated with particular species of cockroaches.

CAVE HABITATS

Caves, mines, and animal burrows are somewhat similar habitats that provide many species of cockroaches with shelter and frequently with food. The microclimates of these cockroach habitats have not been described in detail in the papers cited, but it seems rather obvious that natural caves, man-made caves (mines), and burrows offer relatively stable temperatures and humidities and protection from adverse climatic conditions. Although such cavernicolous animals as birds and bats periodically leave caves to search for food, cockroaches find the accumulated guano and animal and plant detritus an entirely adequate dietary (Chopard, 1938). Cockroaches in mines presumably subsist on the food and feces dropped by man and mine animals (e.g., pit ponies). Food stored in their nests by burrowing animals is undoubtedly utilized by the associated cockroaches.

Cavernicolous cockroaches show varying degrees of dependence on and adaptation to these specialized habitats. Some of the common domiciliary species (_Blatta orientalis_, _Blattella germanica_, and _Periplaneta americana_) may have accompanied man into caves and remained there after he left (Chopard, 1929a, 1936, 1938). Other species, from the paucity of records noting their occurrence in caves, are undoubtedly accidental inhabitants that may never become established. Besides these, however, many other species of cockroaches have established large breeding colonies in caves. Although some of the latter species show very pronounced morphological adaptations to a cave life, many others resemble their noncavernicolous relatives. The possible origin of cavernicolous Orthoptera has been discussed by Chopard (1938).

Cavernicolous cockroaches have been segregated into four groups according to their ability to adapt to their environment and the degree of their specialized evolution (Chopard, 1936, 1938): (1) =Trogloxenes=: Cockroaches that occur in caves in a sporadic fashion (the domiciliary cockroaches and accidentals such as _Ectobius_ and _Heterogamodes_). (2) =Troglophiles=: Cockroaches found habitually in caves (_Symploce_, _Periplaneta cavernicola_). (3) =Guanobies=: Cockroaches that live in the guano of cavernicolous vertebrates (_Gyna_, _Acanthogyna_, _Dyscologamia_, _Pycnoscelus_). (4) =Troglobies=: Cockroaches that apparently cannot live outside of caves and which show very marked adaptive characters (_Alluaudellina_, _Nocticola_, _Spelaeoblatta_, _Typhloblatta_). For complete discussions of these groups including descriptions of the adaptive characters shown by certain genera, the original sources should be consulted.

Although we know very little of the ethology of most of the cavernicolous cockroaches, it is intriguing that three of the six known species of _Nocticola_ are cave dwellers, two are inhabitants of termite nests (p. 315), and one (_N. bolivari_) was found under stones and cement blocks (Chopard, 1950b). In the rather extensive list of cavernicolous cockroaches only two (_Arenivaga grata_ and _Parcoblatta_ sp.) were taken from caves in North America north of Yucatan. All other records are from Africa, Asia, Central America, Europe, West Indies, East Indies, and the Philippine Islands. This we find puzzling. Packard (1888) in his extensive study of the cave fauna of North America listed no cockroaches. Dearolf (1941) found only the above-mentioned _Parcoblatta_ in one of 37 caves in Pennsylvania. Kohls and Jellison (1948) listed no cockroaches among the arthropods from six bat caves in Texas. We would expect _Periplaneta americana_ to inhabit mines in North America, but we have found no such records. Have cockroaches been ignored in fauna collections from North American caves, or has our cave fauna been less extensively studied than that of other parts of the world?

The two species of cockroaches found in mines (_Blattella germanica_ and _Periplaneta americana_) are also found in caves. For this reason we have included them in the list headed Cavernicolous Cockroaches. On the other hand, the cockroaches found in animal burrows are generally different species from those found in caves, so we have grouped these together in a second list.

CAVERNICOLOUS COCKROACHES

=Alluaudellina cavernicola=

_Tanganyika._--From Kulumusi caves, near Tanga. The eyes of this cockroach are reduced to a pair of slender streaks (Shelford, 1910a; Chopard, 1932a).

_East Africa._--Chopard (1936).

=Apotrogia angolensis=

_Belgian Congo._--A troglophile without well-marked adaptive characters. Collected in moist sand on floor of a sandstone grotto inhabited by bats (Chopard, 1927, 1950a). Taken in many caves in Bas Congo (Leleup, 1956).

=Apteroblatta perplexa=

_East Africa._--Accidental inhabitant of cave (Chopard, 1936).

=Arenivaga grata=

_Arizona._--"A female and many nymphs were taken by Flock in the guano in a bat cave in the Tucson Mountains" (Ball et al., 1942).

=Aspiduchus borinquen=

_Puerto Rico._--In limestone cavern by thousands in grass and on walls (Rehn and Hebard, 1927; Rehn, J. W. H., 1951a).

=Aspiduchus cavernicola=

_Puerto Rico._--In limestone cave, in caves inhabited by bats, and apparently seen in other caves well removed from entrance. "In this latter situation great numbers were seen on the side walls and roof" (Rehn, J. W. H., 1951a).

=Blaberus atropos=

_Yucatan._--Found once, in Xmahit cave (Pearse, 1938).

=Blaberus craniifer=

_Yucatan._--Collected within three caves, near the entrances (Pearse, 1938).

=Blaberus giganteus=

_Panama._--Two males and several nymphs were taken under rocks in the second chamber of the Chilibrillo cave; some also were on the walls (Caudell, 1924).

=Blatta lateralis=

_Turkmen S.S.R._--All stages, but more often females and nymphs, were found in the middle and back part of Bakharden cavern, which was inhabited by tens of thousands of bats (Vlasov, 1929).

=Blatta orientalis=

_Turkmen S.S.R._--All stages found in front part of Bakharden bat cave. This cave was uninhabited by man but supported a variety of other animals (Vlasov, 1929).

=Blattella germanica=

_South Africa._--Numerous in a gold mine on the Witwatersrand (Porter, 1930).

_Tonkin._--Chopard (1929a); Colani (1952).

=Byrsotria fumigata=

_Cuba._--Cueva de las Cucarachas, La Pantana, Baracoa, Oriente Province: 21 specimens, "It is evident ... that the species is also a cave inhabitant" (Rehn and Hebard, 1927).

=Deropeltis erythropeza=

_East Africa._--Found at entrance of cave; not a strictly cavernicolous form according to Chopard (1936).

=Ectobius pallidus=

_France._--Nymph in cave in Basses-Pyrénées, accidental inhabitant (Chopard, 1936).

=Ectobius vittiventer=

_Italy._--In detritus at base of entrance shaft of Acquaviva cave in the Venezia Tridentina (Conci, 1951).

=Ectobius= sp.

_Italy._--Found in the heap of saprophytic detritus at the base of the entrance shaft in the Acquaviva cave (Conci, 1951).

=Ergaula scarabaeoides=

_Sumatra._--West coast (Hebard, 1929).

_Malaya._--Found burrowing in bat guano among stones at entrance to caves in Selangor (Chopard, 1919, 1929).

=Euthyrrhapha nigra=

_Madagascar._--Three males and six females in guano in Antsinomy grotto (Chopard, 1949a).

=Gyna kazungulana=

_East Africa._--This species is especially found in caves although it shows no special adaptive characters. It is a typical guanobe (Chopard, 1936).

=Gyna maculipennis=

_Belgian Congo._--Troglophile, guanophile. Found in two caves in Lualaba (Leleup, 1956).

=Gyna tristis=

_Belgian Congo._--In three caves in Uele (Leleup, 1956).

=Heterogamodes krügeri=

_North Africa._--An accidental inhabitant of caves (Chopard, 1938).

=Holocompsa zapoteca=

_Yucatan._--Common throughout rather dry, dusty caves in southern Yucatan (Pearse, 1938).

=Hoplosphoropyga babaulti=

Stated to be a troglophile by Chopard (1938).

=Nocticola caeca=

_Philippine Islands._--Bolívar (1892).

=Nocticola decaryi=

_Madagascar._--A true troglobite according to Chopard (1945).

=Nocticola simoni=

_Philippine Islands._--Bolívar (1892).

=Parcoblatta= sp.

_Pennsylvania._--Found in Merkle cave, Berks County (Dearolf, 1941).

=Periplaneta americana=

IN CAVES

_East Africa._--Its presence in the cave at Shimoni was thought to indicate that man had sought refuge there and brought the cockroaches in with baggage or provisions (Chopard, 1936).

_India._--Many present in cave at Vengurla, the floor of which was covered with bird guano (Abdulali, 1942).

_Madagascar._--Thought to have been introduced into the cave entrance by man (Chopard, 1945, 1949a).

IN MINES

_Great Britain._--In a coal mine at Pontewydd where they had been established for some years (Lucas, 1916). In the Pentre Pit mine where they were abundant (Lucas, 1918). Abundant in a Welch mine 2,166 feet below the surface (Lucas, 1925). This species was found quite commonly in a number of South Wales coal mines; in one deep mine a white-eyed mutant form comprised about 5 percent of the cockroach population for the preceding 11 years (Jefferson, 1958).

_India, western Bengal._--Very numerous in coal mines where the sole food apparently was human faeces (Chandler, 1926).

_South Africa._--Numerous in four deep-level gold mines on the Witwatersrand.

_Sumatra._--Numerous males and females from Sawah Lunto "'from a coal mine where they lived in great numbers on the faeces of miners'" (Hanitsch, 1929).

=Periplaneta australasiae=

_Sarawak._--Found swarming on walls of caves and in soft bird guano in company with _Symploce cavernicola_ (Moulton, 1912).

_Tonkin._--Chopard (1929a); Colani (1952).

=Periplaneta cavernicola=

_Malaya._--Taken on walls of inner caverns, where they were particularly abundant (Chopard, 1919).

=Periplaneta lata=

_Tonkin._--Chopard suggested that its presence in caves is probably linked with man (Chopard, 1929a; Colani, 1952).

=Periplaneta= sp.

_Malaya._--From a cave in Jalor (Annandale et al., 1913).

=Perisphaerus= sp.

_Malaya._--The wingless females and nymphs mined in bats' guano in a cavern of the Jalor caves (Annandale, 1900).

=Polyphaga aegyptiaca=

_Turkmen S.S.R._--Females found in front part of Bakharden bat cave on several occasions (Vlasov, 1929).

_Turkey._--At Magharadjik and Arab Dede, found in caves with various other animals (Lindberg, 1954).

=Polyphaga= sp.

_Burma._--Hsin Dawng Cave, S. Shan States, 1 immature male under stone in complete darkness (Chopard, 1924b).

=Pycnoscelus niger=

_Tonkin._--Apparently not an accidental inhabitant as nymphs were present (Chopard, 1929a; Colani, 1952).

=Pycnoscelus striatus=

_Malaya._--Found burrowing in bats' guano at entrance to caves in Selangor, where it was very abundant 50 to 600 feet from entrance; also on walls of inner cavern (Chopard, 1919, 1929). In the absence of other evidence, the presence of _P. striatus_ in a cave indicates that bats also inhabit the cave (Chopard, 1929a).

=Pycnoscelus surinamensis=

_Assam._--Found 300 to 400 feet from entrance of Siju cave in the Garo Hills (Chopard, 1924b).

_South Celebes._--Hanitsch (1932).

=Spelaeoblatta gestroi=

_Burma._--Chopard stated that this species shows marked characteristics of adaptation to a life in darkness (Bolívar, 1897; Annandale, 1913; Chopard, 1919).

=Symploce breviramis=

_South Celebes._--Hanitsch (1932).

=Symploce cavernicola=

_Sarawak, Borneo._--Swarming on walls of caves and in soft bird guano on the cave floor (Moulton, 1912). Hanitsch (1931) noted that this species was first recorded by Shelford from a cave in Sarawak and that there is a series from a cave in the Oxford University Museum, taken by Banks in 1928.

_Malaya._--On the walls of the inner cavern of a cave at Biserat; the insects covered the walls in places (Chopard, 1919).

_Sumatra._--From Baso cavern, on the west coast (Hebard, 1929).

=Symploce curta=

_South Celebes._--Hanitsch (1932).

=Symploce remyi=

_Tonkin._--This seems to be a true cavernicolous species (Chopard, 1929a; Colani, 1952).

=Tivia macracantha=

_Belgian Congo._--A troglophile without well-marked adaptive characters (Chopard, 1950a). At Haut-Katanga, troglophile and guanophile (Leleup, 1956).

=Tivia= sp.

_Madagascar._--Last-stage nymphs captured in guano in Antsinomy grotto (Chopard, 1949a).

=Typhloblatta caeca=

_India, Assam._--An eyeless species with noticeably elongated appendages (Chopard, 1945).

=Typhloblattodes madecassus=

_Madagascar._--Unpigmented integument and reduced eyes (Chopard, 1945).

=Xestoblatta immaculata=

_Panama._--Found under rocks on guano-covered floor of the Chilibrillo bat caves (Caudell, 1924).

=Unidentified cockroaches=

_Malaya._--The walls of a cave were covered by dense groups of a species of "_Blatta_" (Annandale, 1900).

_England._--"The chief insect pests of the mines are cockroaches, which often swarm in hot mines and those with pit pony stables...." (Hardy, 1941).

COCKROACHES FROM THE BURROWS OF VERTEBRATES

=Arenivaga apacha=

_Arizona._--In the nests of wood rats, _Neotoma_ sp. (Hebard, 1917).

=Arenivaga bolliana=

_Texas._--In the nests of wood rats, _Neotoma_ sp. (Hebard, 1917; 1943a).

=Arenivaga erratica=

_Arizona._--The wingless females were commonly found in burrows of _Dipodomys spectabilis spectabilis_ Merriam, the kangaroo rat. The winged males were never found in the burrows (Vorhies and Taylor, 1922). Found most commonly in wood-rat and ground-squirrel dens in the desert regions (Ball et al., 1942).

=Arenivaga floridensis=

_Florida._--Found in a burrow of _Peromyscus polionotus rhoadsi_ (Bangs), the white-footed mouse (Young, 1949).

=Arenivaga roseni=

_Turkmen S.S.R._--Occasionally found in burrows of _Rhombomys opimus_ Lichtenstein; in the burrows of the desert turtle, _Testudo horsfieldi_ Gray; and frequently in burrows of the ground squirrel, _Spermophilopsis leptodactylus_ Lichtenstein (Vlasov, 1933; Vlasov and Miram, 1937).

=Arenivaga tonkawa=

_Texas._--An immature specimen was found in a prairie-dog hole (Hebard, 1943a).

=Cariblatta lutea=

_Florida._--It has been taken in burrows of the pocket gopher, _Geomys_ sp. (Hubbell and Goff, 1940).

=Euthlastoblatta abortiva=

_Texas._--In the nests of wood rats, _Neotoma_ sp. (Hebard, 1917).

=Parcoblatta fulvescens=

_Texas._--In the nests of wood rats, _Neotoma_ sp. (Hebard, 1917).

=Polyphaga aegyptiaca=

_Turkmen S.S.R._--Nymphs and adult females were often found in burrows of the sand mouse, _Rhombomys opimus_ (Vlasov, 1933).

=Polyphaga indica=

_Turkmen S.S.R._--This species prefers sandy soils where it can be found in burrows of _Spermophilopsis leptodactylus_ and _Pallasiomys meridionalis pennicilliger_ Heptner (Vlasov and Miram, 1937).

=Polyphaga saussurei=

_Tadzhikistan._--Found in burrows of turtles and rodents (Zmeev, 1936).

_Turkmen S.S.R._--Nymphs and adult females are common in burrows of _Rhombomys opimus_ and in burrows of _Testudo horsfieldi_. Its principal habitat is rodent burrows in loess dust, where it is not infrequently found in the food stores of the host (Vlasov and Miram, 1937).

=Pycnoscelus surinamensis=

_Texas._--In the nests of wood rats, _Neotoma_ sp. (Hebard, 1917).

DESERT HABITATS

There is relatively little ecological information about cockroaches that live in deserts, even though certain species, notably _Polyphaga aegyptiaca_, have long been known to inhabit arid zones. In fact, so little is known about the ecology of arid-zone insects in general that it is more a subject for research than for review (Pradhan, 1957). In their account of the cockroaches of Northern Kenya and Jubaland, Kevan and Chopard (1954) describe in some detail the vegetational areas of this arid desert or semidesert country, which averages only about 10 inches of rain per year. The other sources that are cited below contain very little more biological information than the abstracted material that is given under each species.

Nearly all the Polyphaginae are said to be marked xerophiles whose distribution coincides with that of the deserts (Bei-Bienko, 1950). With the exception of _Arenivaga floridana_, the species of Polyphaginae in the United States all occur in the Southwest, where they are (with a few exceptions) the only cockroaches that inhabit the desert regions proper (Hebard, 1917). The Polyphaginae reach their greatest diversity in the deserts of Northern Africa and Anterior and South-Central Asia (Bei-Bienko, 1950). Some of the desert-inhabiting species have also been found under nondesert conditions. This only further exemplifies the plasticity of cockroaches in adapting to different environments.

The ability of desert insects to live under what appear to be extremely unfavorable conditions has been abundantly illustrated by Pradhan (1957). Uvarov (1954) has pointed out that a desert "covers a great variety of landscapes, which provide desert animals with a wide range of habitats, some of them offering very favorable conditions for life." Pradhan (1957) stated that many desert animals avoid the extremes of desert climates by choosing suitable microclimates for diurnal resting places, that a permanent or temporary underground existence is very common among insects in arid zones, and that many nocturnal Orthoptera burrow into the soil or hide under stones where temperatures are lower. For example, the type of _Parcoblatta desertae_ was found under a boulder on the bare desert (Rehn and Hebard, 1909).

Symbiosis with burrowing animals is another solution to the problem of existence in the desert; in fact, symbiosis is a mode of life adopted by nearly half of the desert cockroaches about which we have any information. Vlasov and Miram (1937) found _Polyphaga indica_, _Polyphaga saussurei_, and _Arenivaga roseni_ in the burrows of rodents and desert turtles. In the desert regions of Arizona, females of _Arenivaga erratica_ were found commonly in burrows of the kangaroo rat (Vorhies and Taylor, 1922) and in dens of wood rats and ground squirrels (Ball et al., 1942). _Arenivaga apacha_ and _Arenivaga bolliana_ have also been found inhabiting the nests of wood rats (Hebard, 1917; 1943a). Bei-Bienko (1950) has suggested that the adaptation of desert-inhabiting cockroaches to rodent burrows might enable these insects to survive in the severe climatic conditions of deserts in summer.

Under desert conditions in southern Arizona, the relative humidity outside of the burrows of the kangaroo rat is 1 to 15 percent during the day and 15 to 40 percent at night; but inside the burrows the relative humidity is 30 to 50 percent, and the temperature, even during the day, is below 30° C. (Schmidt-Nielsen, 1949). Thus by living in rodent burrows during the day and going outside at night, the desert cockroaches could avail themselves of the most favorable microclimates obtainable. Presumably whatever food these insects eat provides them with sufficient water to enable them to survive under desert conditions. Bodenheimer (1953) has suggested that the extent of utilization of dew, which is sometimes heavy in the desert, should be investigated; he stated that tenebrionid beetles have been seen in the early morning eating dry [dead?] herbs that were still wet with dew. It is obvious that there is a need for additional detailed information without which we can only guess about the ecology of desert cockroaches.

In the following list we have cited only those species that were stated to have been found under desert conditions. Undoubtedly, related species that have been taken in similar localities are also desert-inhabiting forms, as, for example, other species of _Arenivaga_ that were collected in Texas by Hebard (1943a). In the absence of specific information linking such other species with deserts, we have arbitrarily relegated those forms to the section on outdoor habitats. In addition to the species listed below, desert cockroaches are said to be found in the following genera: _Anisogamia_, _Mononychoblatta_, and _Nymphytria_ (Chopard, 1938).

DESERT COCKROACHES

=Agis orientalis=

_Northern Kenya._--In desert-grass and thorn-bush country; scattered, dry tufts of grasses interspersed among acacia bush and scattered trees (Kevan and Chopard, 1954).

=Arenivaga apacha=

_U.S.A._--Inhabits desert regions of the Southwest, has been found in nests of wood rats (Hebard, 1917).

=Arenivaga bolliana=

_U.S.A._--On gravelly hillocks, in scattered scrub, and in the nests of wood rats in Texas. It is a desert inhabitant in the Southwest (Hebard, 1917; 1943a).

=Arenivaga erratica=

_U.S.A._--Inhabits desert regions of the Southwest (Hebard, 1917). In Arizona it has been found in rodent burrows in the desert (Vorhies and Taylor, 1922; Ball et al., 1942).

=Arenivaga roseni=