Reproductive modes and distribution of benthic decapod crustaceans along the Scotia Arc

ROMERO M.C.,; TAPELLA F.,; LOVRICH G.A.; THATJE S

Berichte zur Polarforschung

Alfred Wegener Institut

Año: 2003 vol. 462 p. 67 - 72

1618-3193

The Antarctic Convergence constitutes the distributional limit for most Magellanic and Atlantic decapod species. A total of 18 benthic decapod species belonging to 10 families and 4 infraorders were collected during the cruise. We found 4 new caridean morphotypes suspected to be new species. At the infraorder level, we can clearly divide the benthic decapod fauna of the South Atlantic and the Scotia Arc into two different distributional areas: the northern part of the Antarctic Convergence still representing “Reptantia” (anomuran and brachyura crabs), whereas south of the convergence only caridean shrimps (“Natantia”) were found. On the species level, we observed an extent of the Magellanic decapod fauna eastwards. The shallow waters off the Sandwich Islands showed an extremely poor decapod fauna. Key species of benthic decapod crustaceans were found at different states of their reproductive cycle. Differences in the reproductive condition of two geographically separated populations of Notocrangon antarcticus were also detected. Differences in the size at gonadal maturity of female Notocrangon antarcticus were also plausible between the populations of South Georgia and South Orkneys Islands.