A review of the species status of the Angayukaksurak charr (Salvelinus anaktuvukensis) of northern Alaska: perspectives from molecular and morphological data

Abstract

"The Arctic, known for its dynamic past, is a significant place to examine drivers of and spatial variation in diversity of life history strategies in fishes. Diversity in heritable life history traits can lead to speciation, as may be the case for the putative Angayukaksurak chair (Salvelinus anaktuvukensis). The goal of this study was to determine the species status of this fish, the only described freshwater species endemic to Alaska. I examined and compared the morphology and genetics of Angayukaksurak charr and its most closely related species, the Dolly Varden (Salvelinus malma). Meristic characters divided the specimens into three forms by major river drainage. Morphological analysis divided the specimens into two forms along nominal species lines based on differences that could also be attributed to differences between life history forms. Sequences from a 550 bp section of mitochondrial d-loop failed to segregate the putative Angayukaksurak charr into a separate lineage, rather placing specimens into two previously resolved lineages of holarctic Arctic chair. In addition, analysis of microsatellite loci showed no clear differentiation between species. Based on these results, I concluded that the Angayukaksurak charr is not a separate species, but rather a resident life history form of the Dolly Varden"--Leaf iii