344 ENTOMOLOGICAL NEWS DESCRIPTION OF THE AQUATIC LARVA AND PUPA OF PARALICHAS TRIVITTIS (COLEOPTERA: PTILODACTYLIDAE),WITH NOTES ON ITS BIOLOGY 1 David H. Funk , Heidi Fenstermacher ABSTRACT: The larva and pupa of Paralichas trivittis (Germar) (Ptilodactylidae: Cladotominae) are described and illustrated from spring seeps in Pennsylvania, USA. Larvae can be distinguished from all other known North American beetles by the presence of a highly modified 8th abdominal segment that is tapered posteriorly to form a spiracular siphon. Larvae were found in organic muck from woodland spring seeps and appeared to be detritivores. Densities of up to 1400 larvae per square meter were observed. Pupation occurred near the larval habitat. Adults were found from June 6 to July 1 1 . Notes on mating behavior, oviposition, egg development and faunal associations are provided. While studying aquatic fauna in woodland spring seeps in southeastern Pennsylvania (Fenstermacher 2002), we found distinctive beetle larvae that were unidentifiable using existing taxonomic keys (e.g., Lawrence 1 99 1 , White and Brigham 1996). Laboratory rearings established that the larva was that of Paralichas (=Odontonyx) trivittis (Germar). In this paper we describe and illustrate the larva and pupa, as well as provide notes on their biology The family Ptilodactylidae occurs worldwide and contains about 40 gen-era and 450 species (Lawrence 1991). Fifteen species from 6 genera occur in the Nearctic. Of those, larvae of Anchytarsus (1 sp.) and Anchycteis (1 sp.) are known to be aquatic, Araeopidius (1 sp.) are semi-aquatic and Ptilodactyla (9 spp.) are terrestrial. Larvae of Lachnodactyla (2 spp.) and Paralichas (1 sp.) are unknown. Paralichas trivittis (Germar) Germar (1824) described the adult as Dasytes trivittis. Guerin-Meneville ( 1 843) erected Odontonyx and later (Guerin-Meneville 1 849) transferred Atopa ornata Melsheimer (1845) to it. Lacordaire (1857) synonymized O. ornata and D. trivittis. Stribling (1986) included Odontonyx in Paralichas White (1859). Lawrence and Newton (1995) formalized this synonymy. Stribling (1986) listed 10 valid Paralichas species (7 Asian, one from Madagascar, one with locality unknown and one [trivittis] from eastern North America) and two undescribed Neotropical species. Adult Paralichas can be distinguished from all other ptilodactylids by the presence of pectinate ungues. Guerin-Meneville (1849) provided figures of the adult, including a color habitus. We illustrate the adult male in Figure 9. 1 Received March 15, 2002. Accepted June 1 8, 2002. Stroud Water Research Center, 970 Spencer Road, Avondale, Pennsylvania 193 1 1. 1 Department of Entomology and Applied Ecology, University of Delaware, Newark, Delaware 19717-1303. ENT. NEWS 1 1 3(5): 344-354 , November & December, 2002
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