Stress Biomarkers in Callinectes exasperatus (Gerstaecker, 1856) (Brachyura: Portunidae) for Environmental Assessment of Estuaries.

• Grant number: 25/12401-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Marcelo Antonio Amaro Pinheiro
• Grantee: Pedro Gabriel Andrade Reis
• Host Institution: Instituto de Biociências (IB-CLP). Universidade Estadual Paulista (UNESP). Campus Experimental do Litoral Paulista. São Vicente , SP, Brazil

Abstract

Estuarine ecosystems, due to their high productivity and ecological relevance, are among the most vulnerable environments to anthropogenic impacts, such as the discharge of domestic, industrial, and agricultural effluents. These pollutants include heavy metals, microplastics, and organic compounds, which can accumulate in local organisms, affecting their physiology and genetics. Decapod crustaceans are widely used as environmental bioindicators, and the species Callinectes exasperatus stands out as a promising sentinel due to its wide distribution in the Western Atlantic and strictly estuarine habits. This study aims to validate the use of C. exasperatus as an indicator of environmental quality in estuaries through the application of genotoxic and cytotoxic effect biomarkers, such as micronucleus frequency (MN¿), nuclear abnormalities (NA¿), and neutral red retention time (NRRT). Field collections will be conducted in two estuarine systems in the state of São Paulo: the Juréia-Itatins (SEJI), considered a preserved reference area, and the Santos-São Vicente estuary (SESSV), impacted by port, industrial, and urban activities. Ten adult males will be captured per site using fish traps (covo-type), followed by hemolymph sampling to assess lysosomal membrane stability (NRRT) and chromosomal damage (MN¿ and NA¿). Data will be statistically analyzed in the R environment, adopting a 5% significance level. It is expected that the biomarkers will reflect differences in impact levels between the estuaries, supporting the validation of C. exasperatus as a sentinel species and expanding the range of tools used in estuarine environmental monitoring in Brazil, which has traditionally focused on Ucides cordatus. (AU)