Reproduction of the shore crab Pachygrapsus transversus (Gibbes, 1850) (Decapoda: Grapsidae) in the Brazilian temperate zone

ABSTRACT

Pachygrapsus transversus is an abundant crab in the intertidal ecosystems in the tropical and temperate coasts of the Atlantic Ocean. This study aims to investigate the egg production (number and volume) in P. transversus in a temperate region (Torres, Rio Grande do Sul, Brazil), comparing between three stages of egg development and four seasons. Ovigerous females were sampled in 2019 at Praia Prainha once per season. In the laboratory, females were identified, measured, and their eggs were classified by stage of development, counted and measured. The main results were: ovigerous females were collected in all seasons, but showed a sharp decrease in winter; fecundity (stage I) was positively correlated with female body size and the highest number of eggs was found in spring and summer; the egg volume was higher in autumn than all other seasons; there was an increase in egg volume during development, while egg loss was only detected in spring. The reproduction of P. transversus presented seasonal and latitudinal differences, which are attributed to environmental conditions.

KEYWORDS:

• Atlantic Ocean
• fecundity
• latitude
• reproduction
• seasonality

Acknowledgements

The authors are indebted to the following foundations for support during the development of this project: Global Mobility Programme (Universidad de Alicante) to RPT, and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (Research Grant 421193/2018-2 and PQ 311340/2021-0 to MT; Master’s degree grant and ongoing PhD fellowship 140920/2021-8 to APH). Thanks are due to members of the Laboratory of Carcinology of the Federal University of Rio Grande do Sul for helping in the sampling activities. Sampling in Rio Grande do Sul was conducted in accordance with current applicable state and federal laws of Brazil, Permanent licence to MT for collection of Zoological Material no. 62356 MMA/IBAMA/SISBIO. Thanks to Kelly Martinez Gomes and Pedro Augusto da Silva Peres for suggestions in the early version of this study and to the anonymous reviewers for their suggestions, which helped improve the quality of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by CNPQ: [Grant Number 421193/2018-2]; Universidad de Alicante.