Host-use pattern and sexual dimorphism reveals the mating system of the symbiotic pea crab Austinixa aidae (Crustacea: Brachyura: Pinnotheridae)

Autor(es)

Peiro, Douglas F. ^[1] ; Antonio Baeza, J. ^{[2, 3, 4]} ; Mantelatto, Fernando L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Lab Bioecol & Crustacean Systemat LBSC, Fac Philosophy Sci & Letters Ribeirao Preto FFCLR, Dept Biol, Postgrad Program Comparat Biol, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Old Dominion Univ, Dept Biol Sci, Norfolk, VA 23435 - USA

^[3] Univ Catolica Norte, Fac Ciencias Mar, Dept Biol Marina, Larrondo 1281, Coquimbo - Chile

^[4] Smithsonian Marine Stn Ft Pierce, Ft Pierce, FL - USA

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Marine Biological Association of the United Kingdom; v. 93, n. 3, p. 715-723, MAY 2013.
• Citações Web of Science: 11

Resumo

Austinixa aidae inhabits burrows of the ghost shrimp Callichirus major at Pereque-acu beach, Ubatuba, Brazil. We described the host-use pattern and sexual dimorphism of A. aidae to test for monogamy given the generality of this mating system in the subfamily Pinnothereliinae (family Pinnotheridae) to which A. aidae belongs. Against expectations, A. aidae lives as solitary individuals within burrows more frequently than expected by chance alone. Additional observations suggested that A. aidae exhibits a polygynandrous mating system with males moving among burrows in search of receptive females. First, only 21% of the burrows harboured heterosexual pairs of crabs and the body size of paired crabs was poorly correlated. This suggests pair instability and frequent shifts among burrows by male and/or female crabs, as reported before for other symbiotic crustaceans in which the body size of paired crabs is poorly correlated. Second, males paired with females that were sexually receptive (without embryos) or that have been receptive recently (carrying early embryos) were found more frequently than expected by chance alone. The above agrees with that reported for species in which sexual pairing does not last long. Third, sexual dimorphism in terms of claw size and coloration was evident. Claws were larger in males than in females, a condition that argues in favour of male-male competition in A. aidae. In addition, the body coloration of males was more similar to the sand grains of the beach than that of females. This sex-specific coloration suggests that males are `better adapted' than females to roam on the surface of the beach in search of burrows because their coloration should diminish the risk of detection by predators. Experiments are needed to reveal the details of the polygynandrous mating system herein inferred for A. aidae and to understand those conditions favouring particular reproductive strategies in symbiotic decapod crustaceans. (AU)

• Processo FAPESP: 10/50188-8 - Crustáceos decápodes: multidisciplinaridade na caracterização da biodiversidade marinha do estado de São Paulo (taxonomia, espermiotaxonomia, biologia molecular e dinâmica populacional) (Biodiversidade Marinha)
• Beneficiário: Fernando Luis Medina Mantelatto
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático