Phylogeny of the tiger catfish group, Pseudoplatystoma, conflicts and resolutions
Abstract
The South American catfish family Pimelodidae (long whiskered catfish) includes the tiger catfish genus of Pseudoplatystoma (Buitrago-Suarez and Burr 2007). These tiger catfish are an economically, culturally, and ecologically valuable genus, with use in commercial fishing, aquiculture, and as top predators (Carvalho-Costa et al. 2011; Saulo-Machado et al. 2010; Nirchio et al. 2013). There are eight species currently described within the genus, including P. corruscans, P. fasciatum, P. tigrinum, P. punctifer, P. reticulatum, P. metaense, P. orinocoense, and P. magdaleniatum (Buitrago-Suarez and Burr 2007). The genus has recently received increased attention regarding the species' possible phylogenetic relationships. The present study used GenBank to create parsimonious phylogenetic trees, and then compared these phylogenetic relationships with previous molecular studies. Five trees were created using genes cytochrome oxidase subunit I (COI), cytochrome-b (cyt-b), recombination activating protein 1 (rag1) exons 1,2,3 from the 3' end and from the 5' end, and recombination activating protein 2 (rag2). The resulting trees formed had congruencies with previous research, finding evidence for P. metaense and P. tigrinum to be a strongly supported clade (Nirchio et al. 2013; Carvalho-Costa et al. 2011). While more research is needed to determine the exact relationship of these eight species, the present study has found strong evidence to further support the clade of P. metaense and P. tigrinum with the Pseudoplatystoma genus.