Comparative anatomy of eyes in deep-sea bivalves (Propeamussiidae)

• Grant number: 24/05327-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2024
• End date: February 28, 2025
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Jorge Alves Audino
• Grantee: Rafael Mandarano Mattiolo
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/02746-9 - Diving in the Mesozoic Marine Revolution from the perspective of benthic and nektonic mollusks, AP.PNGP.PI

Abstract

Photoreception is vital for the survival of several animals in which photoreceptor systems exhibit a wide morphofunctional diversity. Such systems are excellent models for evolutionary studies focused on evolutionary pressures and adaptations to different environments and lifestyles. Bivalves, the second most diverse group of Mollusca, have different types of photoreceptor systems. In Pteriomorphia, a clade with oysters, mussels, scallops, and others, five independent origins of visual systems are known, including mirror eyes in Pectinoidea, which encompasses four families: Pectinidae (the most studied group), Spondylidae, Cyclochlamydidae, and Propeamussiidae. Studies on the Propeamussiidae, especially soft parts, are very scarce, as they are difficult, fragile animals to collect and rarely preserved with soft parts. Considering that propeamussiids occur in aphotic and disphotic zones in deep seas, they are considered key organisms to investigate morphofunctional variations in the visual system. Consequently, the current research proposal aims to investigate the histology of eyes from nine morphotypes of Propeamussiidae, including different genera, acquired from the Muséum National d'Histoire Naturelle (MNHN, Paris), as well as their external morphology, contributing to the acquisition of data for comparative anatomy. The data obtained will be analyzed for interspecific variation and compared with closely related families, i.e., Pectinidae and Spondylidae. Overall, the research project will contribute to a better understanding of the evolution of visual systems in bivalves, mainly in Pectinoidea, in addition to providing original data to investigate the anatomical diversity of mirror eyes in different ecological and evolutionary contexts.