Woundfin Larvae and Early Juveniles-A Descriptive Account

Authors: Snyder, Darrel E.*, Charles, Jennifer A., Bjork, C. Lynn

Year: 2015 (xlvii)

Abstract

The Woundfin, Plagopterus argentissimus (Cyprinidae), is a federally endangered fish endemic to portions of the Lower Colorado River Basin. It historically inhabited the Virgin River, lower Gila River, and the Colorado River between (and probably below to Mexico), but currently remains only in the lower Virgin River (AZ, NV, UT). In the Virgin River, it is one of just six native fishes (all cypriniforms) and one of two belonging to a small group of cyprinids referred to as plagopterins (former tribe Plagopterini), most species of which are uniquely characterized by spinous modifications to the pelvic fin rays and the first principal and adjacent rudimentary rays of the dorsal fin. To document the morphological ontogeny of its previously undescribed larvae and facilitate researcher identification of collected specimens, the Virgin River Resource Management and Recovery Program (with funding by Washington County Water Conservancy District, UT) sponsored developmental study, illustration, and description of Woundfin larvae and early juveniles. Specimens for study and reference were reared, preserved, and provided in 2000, 2006, and 2009 by Dexter National Fish Hatchery and Technology Center (NM; now the Southwestern Native Aquatic Resources & Recovery Center). As presented in this poster, most results were summarized in the standard species-account format of the Larval Fish Laboratory. Copies of the 2011 descriptive account may be viewed also at, or downloaded from, the Virgin River Program website (http://www.virginriverprogram.org/wp-content/uploads/2011/08/Final-WF-species-account.pdf).