Life in the dark: metabolic and cardiorespiratory responses to temperature variation and hypoxia of the troglobitic species of cave catfish, Ancistrus cryptophthalmus Reis, 1987 (Siluriformes: Loricariidae)

• Grant number: 23/15987-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2024
• End date: July 31, 2025
• Field of knowledge: Biological Sciences - Physiology - Compared Physiology
• Principal Investigator: Luciane Helena Gargaglioni Batalhão
• Grantee: Leonardo de Assis
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Air temperatures on Earth have been rising since the Industrial Revolution. Although natural variability plays some role, the preponderance of evidence indicates that human activities, especially emissions of heat-trapping greenhouse gases, are primarily responsible for making our planet hotter. Other human actions have a negative effect on the environment, such as deforestation, pollution and eutrophication of aquatic environments. Cave fauna, in general, can be considered very fragile and highly threatened. This fact only worsens when we mention species considered troglobite (they only constitute source populations within underground habitats). In this sense, it is essential that we clarify the physiological characteristics and understand plasticity in relation to climate change and other anthropogenic actions of subterranean fauna species. Therefore, the present study aims to understand the tolerance to hypoxia (low concentration of environmental oxygen) and thermal sensitivity of the cave catfish species Ancistrus cryptophthalmus, which inhabits caves in the region of São Domingos, Goiás, and is a troglobitic species classified as Endangered (EN) on the Official List of Brazilian Fauna Threatened with Extinction of 2022. Therefore, the objective of the present project is to test the hypothesis that the cave catfish Ancistrus cryptophthalmus has a lower tolerance to increased environmental temperature and hypoxia when compared to a specimen related to the genus Ancistrus sp. of the epigeal environment.