Sexual ratio, reproductive period and seasonal variation of the gonochoric shrimp Hippolyte obliquimanus (Caridea: Hippolytidae)

Autor(es)

Terossi, Mariana ^[1] ; Mantelatto, Fernando L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Lab Bioecol & Crustacean Systemat, Dept Biol, Fac Philosophy Sci & Letters Ribeira Preto FFCLRP, BR-14040901 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MARINE BIOLOGY RESEARCH; v. 6, n. 2, p. 213-219, 2010.
• Citações Web of Science: 20

Resumo

Hippolyte obliquimanus is a small, gonochoric shrimp found in algal substrates along the western Atlantic coast of Brazil, particularly in association with seaweed of the genus Sargassum. We studied population features (sexual ratio, reproductive period and temporal distribution) of H. obliquimanus in southeastern Brazil, including its relationships with the seasonality of banks of this alga. Specimens were collected at two-monthly intervals from March 2005 to January 2006, in Ubatuba Bay. The sex of individuals was checked, and the carapace length measured. In total, 668 individuals were collected: 211 males (0.70-2.50 mm carapace length), 341 non-ovigerous females (0.55-2.90 mm), and 116 ovigerous females (1.55-3.20 mm). Hippolyte obliquimanus showed seasonal-continuous reproduction and variable continuous recruitment. The highest number of animals (75%) was collected in fall-winter. The percentages of ovigerous females/total females (fall-winter: 27%; spring-summer: 26%) and the sexual ratio (fall-winter: 31%; spring-summer: 32%) were practically equal in both periods. The sexual ratio showed a predominance of females in almost all size classes, and we detected a new sex ratio pattern for this species. The seasonal variation in the number of individuals can be related to its migration to deeper areas, due to the decrease in the abundance of Sargassum sp. in shallower waters in spring-summer. (AU)

• Processo FAPESP: 06/61771-0 - Status taxonômico e biológico de duas espécies do gênero Hippolyte Leach, 1814 (Decapoda: Hippolytidae) no Atlântico americano
• Beneficiário: Mariana Terossi Rodrigues Mariano
• Modalidade de apoio: Bolsas no Brasil - Doutorado