Exploring evolutionary mechanisms in the development of the skeletal system of Schizolecis guntheri (Miranda-Ribeiro 1918) (Siluriformes: Loricariidae): phenotypic plasticity, homologies and phylogenetic implications

• Grant number: 24/05420-2
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: August 01, 2024
• End date: January 20, 2025
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Mario Cesar Cardoso de Pinna
• Grantee: Jonatas Santos Lima Pereira
• Supervisor: Eric James Hilton
• Host Institution: Museu de Zoologia (MZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Virginia Institute Of Marine Science, United States
• Associated to the scholarship: 22/15668-6 - Ontogeny of the skeletal system of Schizolecis guntheri (Miranda-Ribeiro 1918) (Siluriformes, Loricariidae): homologies and phylogenetic implications, BP.MS

Abstract

Loricariidae is one of the most diverse families in Siluriformes, occupying the majority of freshwater environments in South America. Immense progress has been made in recent years on knowledge about diversity and phylogenetic relationships of the group. Despite this, information about the ontogeny of Loricariidae remains rudimentary and mostly unexplored. This situation is a severe knowledge gap, because the interaction between development, phylogeny and evolutionary patterns is essential for a full view of the process of biological diversification. This project aims to offer a descriptive-comparative study of the skeletal development of Schizolecis guntheri, which will be the first of its kind with any Hypoptopomatinae, one of the most important subgroups of Loricariidae. The study will provide decisive basic evidence in understanding the origin and homology of some controversial structures (e.g., "antorbital", lacrimal and interopercle) and explore mechanisms of phenotypic plasticity of the skeleton of S. guntheri. An osteological description will be combined with a survey of the range of intraspecific variation and a discussion of the homologies of bones and estimates of heterochronic events. Results will shed light on problems of relevance not only in Loricariidae, but also in Siluriformes as a whole, as well as presenting for the first time a picture of the hierarchical timing and relative pace of phenotypic differentiation in the family.