Comparative study of the ventricular morphology in Otophysi: an evolutionary approach

• Grant number: 19/00450-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: November 01, 2019
• End date: February 05, 2023
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Ricardo Cardoso Benine
• Grantee: Mario Vitor Buzete Gardinal
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The fish heart is composed of six anatomical components arranged in series. Among them, the ventricle stands out for presenting considerable morphological variations between the species related to the external anatomy, organization of the myocardium and distribution of coronary vessels. One of the forms of classification considers it's myoarchitecture and the level of vascularization, allowing to group it into four main types (I-IV). Although this classification is a tool that, at some level, allows inferences about the evolution of ventricular morphology in fish, no analysis using comparative phylogenetic methods has been performed to date. Still, little is known about cardiac morphology and evolution in neotropical freshwater teleosts. Given the above, the objective of this study will be to bring advances in the understanding of ventricular morphology and evolution in freshwater teleosts of the Otophysi lineage. For description and survey of morphological characters, ventricles of 22 species belonging to four orders (Characiformes, Siluriformes, Gymnotiformes, and Cypriniformes) will be submitted to anatomical, histological and ultrastructural studies. Then, a phylogeny of these species will be proposed based on molecular traits (ultraconserved DNA elements) previously sequenced. Finally, the morphological characters will be incorporated into the resulting phylogeny and analyzed by comparative phylogenetic methods to infer the evolution of ventricular morphology. (AU)