Rio Grande Sucker Pantosteus plebeius is Native to the Gila River Basin

• Published in: Copeia 2019-07, Vol.107 (3), p.393-403
• Main Authors: Turner, Thomas F, Pilger, Tyler J, Osborne, Megan J, Propst, David L
• Format: Article
• Language: English
• Subjects: 19th century; Bayesian analysis; Biogeography; Biology; Coastal inlets; Computation; Creeks & streams; Ecology; Endangered & extinct species; Evolution; Fish; Freshwater; Freshwater fish; Genes; Genetic diversity; Headwaters; Hypotheses; Hypothesis testing; Inland water environment; Introgression; Microsatellites; Mitochondrial DNA; Phylogenetics; Population; Populations; Probability theory; River basins; Rivers; Software; Surveys; Translocation; Tributaries; Wildlife conservation
• ISSN: 0045-8511; 2766-1512; 1938-5110; 2766-1520
• DOI: 10.1643/CG-19-202

In the late 1940s, Rio Grande Sucker Pantosteus plebeius was reported in tributaries of the Gila River in the Colorado Basin and presumed to be introduced because of its absence in mid-19th century surveys. We assayed genetic variation at ten microsatellite loci and two mtDNA genes (cyt b and ND4) to test the hypothesis of human-mediated introduction into the Gila within the last century. Phylogeographic analysis indicated that Gila River populations shared recent common ancestry with populations in the Mimbres River. Using approximate Bayesian computation (ABC), we rejected the hypothesis that Rio Grande Sucker was introduced to the upper Gila River within the last century. Rather, we hypothesize an older (∼4000 years before present) headwater capture event that facilitated transfer of fishes from the Mimbres to Sapillo Creek in the Gila Basin. From there, suckers dispersed to the San Francisco River and became established in upland stream habitats. Rio Grande Sucker exhibits low levels (