(Holsinger, 1967) 
Stygobromus pecki is a rare species of crustacean known by the common name Peck's cave amphipod. It is endemic to Texas in the United States, where lives in only two springs in Comal County. It is a federally listed endangered species of the United States, and is listed as Endangered on the IUCN Red List.
This amphipod, like many subterranean species, is eyeless and lacks pigment.
The amphipod is found in Comal Springs, which is owned by the city of New Braunfels, Texas, and Hueco Springs, which is privately owned. This species is threatened by the lowering water levels in the Edwards Aquifer, which feeds the springs in which it dwells. The water in the aquifer has long been drained for human use, in irrigation, for example.
- Inland Water Crustacean Specialist Group (1996). "Stygobromus pecki". IUCN Red List of Threatened Species. Version 2011.2. International Union for Conservation of Nature. Retrieved January 12, 2012.
- Jim Lowry (2010). "Stygobromus pecki (Holsinger, 1967)". World Register of Marine Species. Retrieved January 12, 2012.
- USFWS. Final rule to list three aquatic invertebrates in Comal and Hays Counties, TX, as endangered. Federal Register December 18, 1997.
- Stygobromus pecki. The Nature Conservancy.