Largespring Gambusia

Habitat preferences

Reported habitat associations include streams and small rivers, creeks, springs or subterranean waters.

The source records associations with muck, clay or silt, sand. An association indicates reported use, rather than an exclusive requirement.

Reproduction and parental care

Recorded spawning months are Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec for the source’s reporting region (TX). This is a regional calendar, not a range-wide schedule.

Size and recorded longevity

FishTraits reports a maximum total length of 4.4 centimetres. Some entries use an estimated asymptotic length; this value should not be treated as a certified record catch.

Native range

Springs in the San Marcos and Guadalupe River systems, central Texas (Lee et al. 1980 et seq.; Hubbs et al. 1991; Page and Burr 1991).

Introduction history

Stocks from San Marcos, Texas, were introduced into Comanche Springs and Balmorhea area in 1937 and 1956, respectively (U.S. Fish and Wildlife Service 1982). Dates of other introductions are not known. Introductions into the springs at Balmorhea were separate introductions as the springs are not connected (Hubbs, personal communication). Hendrickson and Brooks (1991) indicated that G. geiseri was stocked into at least one site for conservation purposes, but the authors did not provide details or information on the locality.

Ecological impacts

This species reportedly competes with another spring-dwelling species, the endangered Pecos gambusia G. nobilis and is considered a potential threat to that species' existence (U.S. Fish and Wildlife Service 1982).