Pyrgulopsis chupaderae

This taxon was placed in the genus Pyrgulopsis by Hershler and Thompson (1987) and Hershler (1994) based on re-examination of the type series and published accounts.

Only one remaining population (one was extirpated) exists on private land without accessibility.

This species is endemic to the south end of the Chupadera Mountains in Socorro County, New Mexico, in the Rio Grande drainage; and currently resides in < 20 m of outflow. Formerly, it was probably a resident of the entire cienega, which is less than 5 ha (Hershler, 1994).

Currently this species is a resident of Willow Spring, on the Willow Spring Ranch (formerly La Cienega Ranch) at the south end of the Chupadera Mountains west of Bosque del Apache National Wildlife Refuge headquarters in Socorro County, New Mexico. It is documented only from two hillside groundwater discharges (Taylor, 1987; Hershler, 1994; Lang, 1998), one of which has been extirpated following cattle trampling (USFWS, 2003).

Information on threats is derived primarily from USFWS (2003):
Regional and local groundwater depletion, spring run dewatering, and riparian habitat degradation represent principal threats (Lang, 1998). Natural stochastic events, such as prolonged drought, could adversely affect this species by reducing flow through the aquatic system, thus increasing salinity levels and concentrating the impacts of cattle. Site inspections in 1996 of both springhead habitats revealed substantial impacts resulting from cattle grazing, including efforts to maintain water pump facilities and improve water delivery systems (Lang, 1998). Lang (1998) reported that the Chupadera springsnail population at the most southern spring habitat is extant; repeated sampling efforts between 1995 and 1997 at the northernmost spring have not yielded any individuals. This spring has been heavily impacted by cattle, was devoid of riparian vegetation, and the gravels and cobbles were covered with mud and manure. Benthic samples from this site contained large volumes of cattle manure.

The land containing Willow Spring was sold in 1999. The new property owners have consistently denied access to the spring to personnel from the State of New Mexico. Consequently, the one remaining population of springsnails has not been monitored in recent years. Although representatives from the State of New Mexico approached the landowner in January 2002 to discuss limited access to collect substrate and individuals for a captive propagation facility and to allow limited monitoring, these efforts have not been successful. Moreover, the current landowner is not interested in developing a conservation agreement (B. Lang, pers. comm., 2002). A fire at Willow Spring was reported by New Mexico Department of Game and Fish personnel in January 2002 (B. Lang, pers. comm., 2002). Contact with the landowner regarding the fire effects on the habitat or the species yielded little useful information, but confirmed that the vegetation around the wetlands was intentionally burned. Access to monitor the population was again denied. Therefore, it is unknown whether the fire affected the last remaining Chupadera springsnail population and if so, to what extent (USFWS, 2003).