Synopsis of the Heteroptera or True Bugs of the Galapagos Islands ' 4k. RICHARD C. JROESCHNE,RD SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 407 SERIES PUBLICATIONS OF THE SMITHSONIAN INSTITUTION Emphasis upon publication as a means of "diffusing knowledge" was expressed by the first Secretary of the Smithsonian. In his formal plan for the Institution, Joseph Henry outlined a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge." 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The publications are distributed by mailing lists to libraries, universities, and similar institutions throughout the world. Papers or monographs submitted for series publication are received by the Smithsonian Institution Press, subject to its own review for format and style, only through departments of the various Smithsonian museums or bureaux, where the manuscripts are given substantive review. Press requirements for manuscript and art preparation are outlined on the inside back cover. Robert McC. Adams Secretary Smithsonian Institution SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 407 Synopsis of the Heteroptera or True Bugs of the Galapagos Islands Richard C. Froeschner SMITHSONIAN INSTITUTION PRESS City of Washington 1985 ABSTRACT Froeschner, Richard C. Synopsis of the Heteroptera or True Bugs of the Galapagos Islands. Smithsonian Contributions to Zoology, number 407, 84 pages, 43 figures, 1 table, 1985. Presented are keys to species, literature and specimen records,-and list of species by island (with map). The present Heteroptera fauna contains 109 species in 61 genera; of these, Tempyra biguttula (Lygaeidae) and Tytthus parviceps (Miridae) are reported as new to the islands and the species formerly listed as Jadera sanguinolenta (Rhopalidae) is described as the new species, Jadera silbergliedi. With the exception of one species that belongs to an Old World genus, this fauna appears to be derived from American forms. One new generic synonymy is proposed: Aknisus McAtee is made a junior synonym of Metacanthus Costa, with the resulting new combination Metacanthus galapagensis (Barber). OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus). Library of Congress Cataloging in Publication Data Froeschner, Richard C. Synopsis of the Heteroptera or true bugs of the Galapagos Islands. (Smithsonian contributions to zoology ; no. 407) Bibliography: p. Includes index. Supt. of Docs, no.: SI 1.27:407 I. Heteroptera—Galapagos Islands—Classification. 2. Insects—Classification. 3. In- sects—Galapagos Islands—Classification. I. Title. II. Series. QL1.S54 no. 407 591s [595.7'54'098665] 84-600217 [QL522.8.G34] Contents Page Introduction 1 Acknowledgments 5 Key to Galapagos Families of Heteroptera 5 Synopses of Galapagos Families 7 Family ANTHOCORIDAE Amyot and Serville 7 Family BERYTIDAE Fieber 10 Family CIMICIDAE Latreille 11 Family COREIDAE Leach 11 Family CORIXIDAE Leach 12 Family CYDNIDAE Billberg 13 Family GERRIDAE Amyot and Serville 15 Family LYGAEIDAE Schilling 18 Family MESOVELIIDAE Douglas and Scott 23 Family MIRIDAE Hahn 24 Family NABIDAE Costa 39 Family PENTATOMIDAE Leach 40 Family PLEIDAE Fieber 44 Family PYRRHOCORIDAE Amyot and Serville 44 Family REDUVIIDAE Latreille 45 Family RHOPALIDAE Amyot and Serville 49 Family SALDIDAE Amyot and Serville 52 Family STENOCEPHALIDAE Dallas 53 Family TINGIDAE Laporte 54 Family VELIIDAE Amyot and Serville 56 Appendix 58 Names of Individual Islands of the Galapagos Islands 58 Map of the Galapagos Islands 59 List of Heteroptera by Islands 60 Literature Cited 63 Figures 1-43 72 Index 80 in Synopsis of the Heteroptera or True Bugs of the Galapagos Islands Richard C. Froeschner Introduction idae on these islands and the similar studies of the Saldidae by Polhemus (1968a), the Tingidae Before one can travel to a desired destination by Drake and Froeschner (1967), the Lygaeidae he must gain direction by establishing his current by Ashlock (1972), and the aquatic Heteroptera point of existence. The aim of the present study by Bachmann(1979). is to establish such a point in the Heteropterology The present study was begun as simply another of the Galapagos Islands. In view of the limited list, this one based on a collection made in 1970 number of Heteropterists who have done spe- (this year generally not cited in text) by the late cialized collecting on the Galapagos Islands and Robert Silberglied; but the untimely death of the consequent incompleteness of knowledge that talented colleague in an airplane crash de- about their Heteroptera, the following numbers manded a more solid contribution dedicated to and conclusions must be considered quite tenta- his memory. Scholars who carry on biological tive. Much more study is needed before com- studies of insects will find inspiration in his stud- fortable confidence can be attained. ies and, hopefully, will find assistance in this The Galapagos Islands! Magical words to the synopsis dedicated to him. biologist! Words recalling giant tortoises, honey Detailed conclusions concerning the Heterop- creeper birds, Charles Darwin, and evolution; all tera of the Galapagos Islands must be made with associated with these islands in the foundation of great caution because the state of our knowledge modern biology. Yet, study of the Heteroptera about the insects on those islands and elswhere or true bug fauna of these islands has languished. in tropical America is probably quite incomplete True, there have been a few lists of Heteroptera (with many undescribed species, many relatively collected there, but these generally represent uncollected areas, and inadequate observations little more than enumerations of taxa with a on most forms) and because of the dearth of smattering of fortuitous observations of habits, phylogenetic analyses. A second misleading as- biology, and perhaps ecology. Exceptions to that pect of the records of Heteroptera on the Gala- type of study are Carvalho and Gagne's (1968) pagos Islands may result from the continued illustrated, taxonomic synopsis of the family Mir- enumeration over the years of forms that, in some instances, are based on a single report made Richard C. Froeschner, Department of Entomology, National nearly a half century ago. The lack of represen- Museum of Natural History, Smithsonian Institution, Washing- ton, DC. 20560. tation in subsequent collections raises the ques- 1 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY tion of whether or not these forms have actually speciation and hence leads to the conclusion of maintained themselves as part of the local fauna. probable relatively recent invasions. In contrast, The known Heteroptera fauna of the Galapa- certain genera of the family Miridae and one gos Islands may be described as oceanic insular. genus of Reduviidae do exhibit marked specia- It is characterized by a few species (109 in 61 tion as three of them each have five or more genera) scattered irregularly in a few families (20 species known only from this archipelago. Such of the 53) occurring on the closest continent— speciation could have occurred because these South America some 900 kilometers to the genera have been established on the islands for east—plus the puzzling presence of a lone species a longer time or because their rate of speciation from the Old World family Stenocephalidae. is more rapid than that of the other genera of The presence of these 109 species could be ac- Heteroptera that are present. counted for by a minimum number of 81 inva- Generalized discussions of the Galapagos Is- sions (estimated by assuming whether or not the land fauna often leave the impression of a single sister-species of each species developed in the continuous fauna being involved. Actually some Galapagos Islands) plus some speciation after cer- 45 separate islands and individually exposed tain of the ancestors reached the islands. Of those rocks are listed for the archipelago in Wiggins 109 species, 77 are known only from the Gala- and Porter (1971, table 1) who also give the pagos Islands. A further oceanic insular charac- estimated surface area for each. Of these islands, teristic for this fauna is the relatively restricted seven exceed 100 square kilometers (the largest, number of fresh-water inhabitants. Only two by far, being Isabela with 5847 square kilome- "aquatic" (subsurface dwellers) families are rep- ters); 11 are between one and 99 square kilo- resented: the Pleidae, by a single unidentified