Molecular evidence for cryptic species in a narrowly endemic western North American springsnail (Pyrgulopsis gilae)

Abstract

Pyrgulopsis gilae is a small springsnail that is narrowly distributed along the forks of the upper Gila River and currently being managed as a threatened and sensitive species by the State of New Mexico and United States Forest Service, respectively. A previous phylogeographic study of this species based on mitochondrial COI sequences delineated substantial divergence between several populations along the lower and upper reaches of the East Fork Gila River. The present study surveyed COI variation among a larger number of populations across the entire geographic range of P. gilae. Three haplotype groupings were delineated that were congruently resolved as clades by a Bayesian analysis. One of the clades was composed of populations along the lower East Fork and mainstem Gila River and corresponds to P. gilae as originally circumscribed. The other two clades were composed of populations along the Middle Fork and upper East Fork Gila River that were recently referred to P. gilae. These three geographically isolated clades do not share any haplotypes, have significant F ST values, and are differentiated from each other by 3.9-6.3 % sequence divergence. Based on this evidence we suggest that the clades represent distinct species and should be managed as separate conservation units pending taxonomic revision of P. gilae. This study provides additional evidence that geographically disjunct subunits of Pyrgulopsis species often represent distinct monophyletic lineages that may warrant formal taxonomic recognition, and thus underscores the importance of finescale conservation genetics studies of these imperiled organisms.

Use of species delimitation approaches to assess biodiversity in freshwater planaria (Platyhelminthes, Tricladida) from desert springs

“…the West Fork of the Gila River drains into the Gulf of California, whereas the Pecos River drains into the Gulf of Mexico), the locally endemic putative species might be a product of past vicariant events and prolonged isolation. Vicariant events followed by speciation are hypothesized in other spring‐dwelling species in the region; for example, amphipods (Adams et al, ) and hydrobiids (Liu, Hershler, Lang, & Davies, ). However, the presence of the widely distributed putative species cannot be explained by vicariant events; other ecological or evolutionary processes are likely to dictate the current distribution of this taxon.…”

“…hydrobiids (Liu, Hershler, Lang, & Davies, 2013 Although passive dispersal is not common in freshwater or marine planaria (but see Sluys, Kawakatsu, & Yamamoto, 2010;Sluys et al, 2015), natural and anthropogenic passive dispersal in terrestrial planaria is well documented ( Alvarez-Presas, Mateos, Tudo, Jones, & Riutort, 2014;Justine et al, 2015;Sluys, 1995). Future population genetic studies of these planaria are necessary to increase understanding of historical and contemporary gene flow among populations.…”

Evaluating the influence of connectivity and distance on biogeographical patterns in the south‐western deserts of North America

“…Pyrgulopsis (Hydrobiidae) is one of the most diverse aquatic snails in North America, which consists of 134 species (Liu et al ., ). They have diversified extensively in the desert south‐west, and are found primarily in springs.…”

Five new cryptic freshwater gastropod species from New Caledonia (Caenogastropoda, Truncatelloidea, Tateidae)

“…Haase et al 2007 , Delicado and Ramos 2012 ). Given the mosaic nature of evolution of these small gastropods with morphologically as well as genetically cryptic species (e.g., Haase et al 2007 , Haase 2008 , Zielske et al 2011 , Delicado and Ramos 2012 , Liu et al 2013 ), we do not adhere to a fairly strict scheme of species identification as advocated elaborately e.g. by Schlick-Steiner et al (2010) .…”