* Shore Flies of the Belizean Cays (Diptera: Ephydridae) WAYNE N.MATHIS m I SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 592 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." This theme of basic research has been adhered to through the years by thousands of titles issued in series publications under the Smithsonian imprint, commencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Contributions to Anthropology Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to the Marine Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Folklife Studies Smithsonian Studies in Air and Space Smithsonian Studies in History and Technology In these series, the Institution publishes small papers and full-scale monographs that report the research and collections of its various museums and bureaux or of professional colleagues in the world of science and scholarship. 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. I. Michael Heyman Secretary Smithsonian Institution SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 592 Shore Flies of the Belizean Cays (Diptera: Ephydridae) Wayne N. Mathis SMITHSONIAN INSTITUTION PRESS Washington, D.C. 1997 ABSTRACT Mathis, Wayne N. Shore Flies of the Belizean Cays (Diptera: Ephydridae). Smithsonian Contributions to Zoology, number 592, 77 pages, 258 figures, 6 tables, 1997.—Shore flies (Diptera: Ephydridae) from the Belizean cays are reviewed, including the description of one new genus (Garifuna) and five new species (Discocerina (Discocerina) juniori, Polytrichophora reginae, Guttipsilopa (Nesopsilopa) dianneae, Paralimna (Paralimna) fellerae, and Garifuna sinuata). Although the known shore-fly fauna of these cays is relatively diverse, comprising 56 species in 31 genera, none of the species is thought to be endemic, i.e., the species are introductions from the mainland. The subfamily Gymnomyzinae has greatest species diversity on the cays, especially the tribe Discocerinini, which has 12 species in three genera. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Annals of the Smithsonian Institution. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus). Library of Congress Cataloging-in-Publication Data Mathis, Wayne N. Shore flies of the Belizean cays (Diptera:Ephydridea) / Wayne N. Mathis. p. cm. — (Smithsonian contributions to zoology ; no. 592) Includes bibliographic references (p. 75) 1. Ephydridae—Belize. 2. Ephydridae—Belize—Classification. I. Title. II. Series. QL1.S54 no.592 [QL537.E7] 590 s-dc21 [595.77'4] 97-34780 30 The paper used in this publication meets the minimum requirements of the American National Standard for Permanence of Paper for Printed Library Materials Z39.48—1984. Contents Page Introduction 1 Methods and Materials 1 Acknowledgments 2 Island and Habitat Descriptions 2 Systematics 10 Key to Subfamilies of Ephydridae 10 Subfamily GYMNOMYZINAE Latreille 10 Key to Tribes and Genera of Gymnomyzinae Occurring on Belizean Cays ... 10 Tribe GYMNOMYZINI Latreille 12 Genus Athyroglossa Loew 12 1. Athyroglossa (Athyroglossa) glaphyropus Loew 12 Genus Mosillus Latreille 12 2. Mosillus stegmaieri Wirth 12 Genus Placopsidella Kertesz 12 3. Placopsidella cynocephala Kertesz 12 Tribe GASTROPINI Cresson 15 Genus Gastrops Williston 15 4. Gastrops niger Williston 15 Tribe OCHTHERINI Dahl 17 Genus Ochthera Latreille 17 5. Ochthera loreta Cresson 17 Tribe ATISSINI Cresson 18 Genus Atissa Haliday 18 6. Atissa luteipes Cresson 18 Genus Ptilomyia Coquillett 19 Key to Species of Ptilomyia Occurring on Belizean Cays 19 7. Ptilomyia lobiochaeta Sturtevant and Wheeler 20 8. Ptilomyia parva (Williston) 20 9. Ptilomyia mabelae (Cresson) 20 Tribe HECAMEDINI Mathis 20 Genus Allotrichoma Becker 20 Key to Species of Allotrichoma Occurring on Belizean Cays 20 10. Allotrichoma (Pseudohecamede) adustum Mathis 20 11. Allotrichoma {Pseudohecamede) abdominale (Williston) 21 Genus Diphuia Cresson 23 12. Diphuia nasalis Wirth 23 Genus Hecamede Haliday 23 13. Hecamede (Hecamede) brasiliensis Cresson 23 Tribe LIPOCHAETINI Becker 23 Genus Glenanthe Haliday 23 Key to Species of Glenanthe Occurring on Belizean Cays 26 14. Glenanthe ruetzleri Mathis 26 15. Glenanthe caribea Mathis 27 16. Glenanthe litorea Cresson 27 Genus Lipochaeta Coquillett 28 17. Lipochaeta slossonae Coquillett 28 in SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Genus Paraglenanthe Wirth 29 19. Paraglenanthe bahamensis Wirth 29 Tribe DISCOCERININI Cresson 30 Genus Discocerina Macquart 30 Key to Species of Discocerina Occurring on Belizean Cays 30 18. Discocerina {Discocerina) flavipes Cresson 31 20. Discocerina {Discocerina) obscurella (Fallen) 32 21. Discocerina {Discocerina) juniori, new species 33 22. Discocerina {Lamproclasiopa) nitida Cresson 34 23. Discocerina {Lamproclasiopa) mera Cresson 34 Genus Hydrochasma Hendel 34 Key to Species of Hydrochasma Occurring on Belizean Cays 34 24. Hydrochasma incisum (Coquillett) 36 25. Hydrochasma faciale (Williston) 36 26. Hydrochasma species 36 Genus Polytrichophora Cresson 36 Key to Species of Polytrichophora Occurring on Belizean Cays 36 27. Polytrichophora agens Cresson 36 28. Polytrichophora conciliata Cresson 39 29. Polytrichophora pulchra (Cresson) 39 30. Polytrichophora reginae, new species 39 Tribe PSILOPINI Cresson 42 Genus Ceropsilopa Cresson 42 Key to Species of Ceropsilopa Occurring on Belizean Cays 42 31. Ceropsilopa coquilletti Cresson 42 32. Ceropsilopa costalis Wirth 42 33. Ceropsilopa nasuta Cresson 43 Genus Leptopsilopa Cresson 44 34. Leptopsilopa similis (Coquillett) 44 Genus Clasiopella Hendel 44 35. Clasiopella uncinata Hendel 44 Genus Guttipsilopa Wirth 44 Key to Species of Guttipsilopa Occurring on Belizean Cays 44 36. Guttipsilopa {Nesopsilopa) dianneae, new species 44 37. Guttipsilopa {Nesopsilopa) umbrosa (Loew) 47 Genus Paratissa Coquillett 48 Key to Species of Paratissa Occurring on Belizean Cays 48 38. Paratissa neotropica Mathis 48 39. Paratissa semilutea (Loew) 49 Subfamily HYDRELLIINAE Robineau-Desvoidy 50 Key to Tribes and Genera of Hydrelliinae Occurring on Belizean Cays 50 Tribe HYDRELLIINI Robineau-Desvoidy 50 Genus Hydrellia Robineau-Desvoidy 50 40. Hydrellia cavator Deonier 51 Tribe NOTIPHILINI Bigot 51 Genus Notiphila Fallen 51 41. Notiphila {Notiphila) erythrocera Loew 51 Tribe DRYXINI Zatwarnicki 53 Genus Paralimna Loew 53 Key to Species of Paralimna Occurring on Belizean Cays 53 42. Paralimna {Paralimna) multipunctata Williston 54 43. Paralimna {Paralimna) fellerae, new species 54 44. Paralimna {Phaiosterna) obscura Williston 56 45. Paralimna {Phaiosterna) decipiens Loew 59 NUMBER 592 Subfamily ILYTHEINAE Cresson 60 Key to Tribes and Genera of Ilytheinae Occurring on Belizean Cays 60 Tribe ILYTHEINI Cresson 60 Genus Zeros Cresson 60 Key to Species of Zeros Occurring on Belizean Cays 60 46. Zeros fenestralis (Cresson) 60 47. Zeros flavipes (Williston) 60 48. Zeros obscurus (Cresson) 60 Tribe HYADININI Phillips et al 60 Genus Hyadina Haliday 60 Key to Species of Hyadina Occurring on Belizean Cays 61 49. Hyadina bulbosa Clausen 61 50. Hyadina flavipes Sturtevant and Wheeler 61 Tribe PHILYGRIINI Lizarralde de Grosso 61 Garifuna, new genus 61 51. Garifuna sinuata, new species 62 Subfamily EPHYDRINAE Zetterstedt 64 Key to Tribes and Genera of Ephydrinae Occurring on Belizean Cays 64 Tribe EPHYDRINI Zetterstedt 64 Genus Cirrula Cresson 64 52. Cirrula austrina (Coquillett) 64 Genus Dimecoenia Cresson 65 53. Dimecoenia spinosa (Loew) 65 Tribe SCATELLINI Wirth and Stone 66 Genus Haloscatella Mathis 66 54. Haloscatella muria (Mathis) 66 Genus Scatella Robineau-Desvoidy 66 Key to Species of Scatella 66 55. Scatella (Scatella) obscura Williston 67 56. Scatella (Scatella) favillacea Loew 68 Discussion and Summary of Shore-Fly Diversity and Island Zoogeography 68 Literature Cited 75 Shore Flies of the Belizean Cays (Diptera: Ephydridae) Wayne N. Mathis Introduction known distributions for many species included records from one or all of the adjacent countries. Thus the goal, to an extent, The Smithsonian Institution has conducted and sponsored was to verify and document the expected fauna. research on the cays of Belize, especially those in the Stann Not all of the findings, however, could be categorized as Creek District, since 1972. These studies have mostly dealt "expected." A few surprises are typical of most studies in with various aspects of the marine fauna and flora, but since biological systematics, and, in this work, several taxa were 1984 there also has been a concerted effort to study the