Breeding period of the spider crab Mithraculus forceps (A. Milne Edwards) (Crustacea, Majidae, Mithracinae)in the southeastern Brazilian coast

Abstract

Investigations concerning to the breeding period of brachyuran crabs provide fundamental information to determine their reproductive cycle, and also to establish management plans for species mainly in protected areas. This study provides data on the breeding period of M.forceps (A. Milne Edwards, 1875) in the southeastern Brazilian coast. Monthly samplings were carried out during a one year-round. A catch effort of approximately four hours was allocated to each monthly survey. The breeding intensity was determined based on the percentage of ovigerous crabs within the whole adult female population. A total of 137 adult females was obtained, from which 80.3% presented eggs attached on their pleopods. Ovigerous females were observed yearround, usually comprising more than 60% of sampled adult females. The ovigerous frequency was not statistically correlated to the environmental analyzed factors.