Population Structure and Reproductive Biology of Two Sympatric Species of Persephona (Brachyura: Leucosiidae) off Northeastern Brazil

The objective of this study was to evaluate the population structure and reproductive biology of Persephona lichtensteinii and P. puncata off Sergipe, two common species found in the bycatch of shrimp trawlers. Four samples of 6 kg were collected monthly from trawlers based in Pirambu-Sergipe. All individuals of Persephona were separated, identified, and weighed (TW, total weight, g). Carapace length (CL, mm) and width (CW, mm) were measured, and the sex and stage of morphological maturity identified. A total of 312 individuals of P. lichtensteinii (174 females; 138 males) and 160 specimens of P. punctata (46 females; 114 males) were analyzed. The overall sex ratio differed from 1:1 for both species. Size and weight of Persephona lichtensteinii were lower than P. punctata. Females of P. lichtensteinii were larger and heavier than males, while P. punctata did not show this sexual dimorphism. Morphometric relationships (CL-CW and TW-CW) were different between sexes for both species. The size at first morphological maturity (CWm) of P. lichtensteinii was 17.0 mm and 18.2 mm for females and males, respectively. For P. punctata, CWm was 23.5 mm for females and 26.5 mm for males. At lower latitude, both maximum size (CWmax) and CWm were lower, which may be associated with maintenance of the CWm/CWmax ratio. The reproduction was continuous, with a peak in May–October for P. lichtensteinii. To the best of our knowledge, this is the first study analyzing the population structure and reproductive biology of these leucosiids in lower latitude regions along the Brazilian coast.