INTEGRATING MORPHOLOGICAL AND MOLECULAR DATA IN THE TAXONOMIC AND PHYLOGENETIC STUDY OF THE MINIATURE FISH PRIOCHARAX WEITZMAN & VARI (TELEOSTEI, CHARACIFORMES, CHARACIDAE)

• Grant number: 24/00680-6
• Support Opportunities: Scholarships in Brazil - Scientific Journalism
• Effective date (Start): May 01, 2024
• Effective date (End): October 31, 2024
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: George Mendes Taliaferro Mattox
• Grantee: Isabela Ferreira Resende
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 17/01970-4 - Integrating morphological and molecular data in the taxonomic and phylogenetic study of the miniature fish Priocharax Weitzman & Vari (Teleostei, Characiformes, Characidae), AP.JP

Abstract

The Neotropical region harbors the most diverse freshwater ichthyofauna in the world, with manydiminutive forms. Miniature fishes are those whose adults do not grow over 26 mm of standard lengthand include more than 210 Neotropical species, a third in the family Characidae. Priocharax is a genusfrom the Amazon with three of the smallest characids known, characterized mainly by the retention ofthe larval pectoral fin in adults. Priocharax was proposed as closely related to the subfamilyHeterocharacinae, but the relations among the genera in this subfamily are yet to be tested in light ofnew evidence including the molecular approach. The amount of samples of Priocharax in collections hasconsiderably increased, revealing new records and morphological variations that allow recognizingadditional undescribed species. However, due to its inherent fragility, freshly collected and adequatelypreserved samples are needed for a proper morphological study since old specimens deposited inmuseums lose scales, colour and decalcify, impeding a detailed morphological approach. I hereinpropose seven fieldtrips to localities of confirmed records of Priocharax in order to have properlypreserved material for osteological and other morphological studies, compilation of a tissue collection ofall species, in addition to photographs of the live fish and their localities. Tissue samples will beincorporated to others already available, allowing a DNA barcode study to complement the taxonomicinvestigation, and an approach using six molecular markers to access the phylogenetic relationships ofPriocharax at intra- and intergeneric levels.