Synonyms and other taxonomic changes
Stygobromus pecki (Holsinger)
Orig. Comb: Stygonectes pecki Holsinger 1967
Explanation of Names
The first recorded specimen of the amphipod Stygobromus (=Stygonectes) pecki (Holsinger 1967) was collected by Peck at Comal Springs in June 1964. Reddell collected a second specimen at the same place in May 1965. In 1967, Holsinger named the species Stygonectes pecki, in Peck's honor, selecting the 1965 specimen as the type specimen. Later he included all the nominal Stygonectes species in the synonymy of the large genus Stygobromus. The FWS Service used "cave amphipod" as a generic common name for members of this genus, and this name was simply transliterated as "Peck's cave amphipod" without reference to a particular cave.
Range
endemic to Comal Springs and Hueco Springs, both in Comal Co., TX -
Map (1)(2)Habitat
Peck's cave amphipod is a subterranean, aquatic crustacean.
Like all members of the exclusively subterranean genus Stygobromus, this species is eyeless and unpigmented, indicating that its primary habitat is a zone of permanent darkness in the underground aquifer feeding the springs. Above ground, individuals are easy prey for predators, but they usually take shelter in the rock and gravel crevices and may succeed in reentering the spring orifice. Barr (1993) got most specimens in drift nets at spring orifices and found them less often as she moved downstream, supporting the notion that they may be easy prey and do not likely survive for long outside the aquifer.
Remarks
Federally listed as an endangered species.
Texas considers this to be a "Species of Greatest Conservation Need" (SGCN)
(3)Print References
Arsuffi, T.L. (1993) Status of the Comal Springs Riffle Beetle (Heterelmis comalensis Bosse, Tuff, and Brown), Peck's Cave Amphipod (Stygobromus pecki Holsinger), and the Comal Springs Dryopid Beetle (Stygoparnus comalensis Barr and Spangler). Prepared for the U.S. Fish and Wildlife Service. 25 pp.
Barr, C.B. (1993) Survey for two Edwards Aquifer invertebrates: Comal Springs dryopid beetle Stygoparnus comalensis Barr and Spangler (Coleoptera: Dryopidae) and Peck's cave amphipod Stygobromus pecki Holsinger (Amphipoda: Crangonyctidae). Prepared for U.S. Fish and Wildlife Service. 70 pp.
Fitzpatrick, J.F., Jr. (1983) How to Know the Freshwater Crustacea. Wm. C. Brown Co. Publishers. Dubuque, Iowa. 277 pp.
Holsinger, J.R. (1967) Systematics, speciation, and distribution of the subterranean amphipod genus Stygonectes (Gammaridae). Bull. U.S. Nat. Mus. 259: 1-176.
Holsinger, J.R. (1972) Biota of Freshwater Ecosystems, Identification Manual No. 5: The Freshwater Amphipod Crustaceans (Gammaridae) of North America. Environmental Protection Agency, Washington, D.C. 89 pp.
Karaman, G.S. (1974) 59. Contribution to the knowledge of the Amphipoda. Revision of the genus Stygobromus Cope 1872 (Fam. Gammaridae) from North America. Glasnik Republickog Zavoda Za Zastitu Prirode, 7: 97–125.
