Platyparnus, a new genus of Dryopidae from the Guiana Shield (Coleoptera: Byrrhoidea, Dryopidae)

ABSTRACT

Platyparnus gen. n. is erected to include three species of Helichus Erichson, 1847, from the Guianas of northern South America. Proposed taxonomic reassignments are Platyparnus bollowi (Hinton, 1939) comb. n., Platyparnus frater (Hinton, 1939) comb. n, and Platyparnus gibbicollis (Hinton,1939) comb. n. A description of the previously unknown male of P. gibbicollis is provided. The males of these species exhibit unique, sexually dimorphic modifications of the legs. Included are figures illustrating external morphology and male genitalia of the species, images of the holotypes, and notes on habitat and behaviour. A taxonomic key to the species of Platyparnus gen. n. is furnished, as well as a key to all known aquatic and semiaquatic Neotropical dryopid genera.

urn:lsid:zoobank.org:pub:A51F9960-7C35-44F4-9ADC-00C5EA08AC52

KEYWORDS:

• Platyparnus
• Dryopidae
• new genus
• long-toed water beetles
• taxonomy
• identification keys
• Guiana Shield
• Neotropics

Acknowledgements

Collecting and export permits in French Guiana were made available from the Collectivité Territoriale de Guyane according to the DIAG project (Convention N°APA-973-13). Hydreco Guyane, the Office de l'Eau de Guyane, the Direction de l'Environnement de l'Aménagement et du Logement de Guyane and the Parc Amazonien de Guyane are thanked for providing financial and technical support. Simon Clavier (HYDRECO Guyane) organised and led the collecting trip and provided logistical assistance. Christine Taylor (Natural History Museum, London, UK) kindly provided the holotype photographs of Helichus bollowi, H. frater, and H. gibbicollis which appear in this paper. Stéphane Hanot (Africa Museum, Tervuren, Belgium) likewise provided holotype photographs of Pelonomus inexpectatus for comparison. Phil Perkins (Museum of Comparative Zoology, Cambridge, MA, USA) generously donated his dryopid specimens from Guyana. Rachael Diaz-Bastin (California Academy of Sciences, San Francisco, CA, USA) photographed and assembled the genitalia plates. We thank Robert Sites (University of Missouri, Columbia, MO, USA) for providing the close-up images of the legs and a photograph of the stream microhabitat. Sara Alexander (National Museum of Natural History, Smithsonian Institution, Washington, DC, USA) assisted us with information about the Biological Diversity of the Guiana Shield Program.

Disclosure statement

No potential conflict of interest was reported by the authors.