Abundância e diversidade da assembléia de crustáceos decápodes dentro e fora de uma pradaria de Ruppia maritima L., no estuário da Lagoa dos Patos (RS-Brasil)

Abstract

Fortnightly beam trawl samples, collected daily and nightly, were used to ... and diversity of decapod crustaceans inhabiting widgeon grass (Ruppia marítima. Linnaeus, 1753) and nearby unvegetated habitats in the shallow water of Patos Lagoon estuary, from December/1994through March/'l 995, following Ruppia bed's developmentdevelopment and senescence. Collections at both study sites produced 26,325 individualsand six decapod species: Penaeus paulensis Peres-Farfante, 1967, Palaeomonetes argentinus (Nobil, 1901, Callinectes sapidus Rathbun, 1895, Calinectes danae Smith, 1869, Cyrtograpsus angulatus Dana, 1851, and Rhithropanopus harrisse Gould, 1841. Abundance was significantly higher in Ruppia's meadows than in unvegetated areas, except for the crab C.danae. As well, diversity was righer in widgeon beds, mainly because the crustaoeanss abundance was more evenly distributed in the vegetated habtat. Patos Lagoon widgeon beads play a nursery role for decapod crusataceans, including commercially important cruantaceans species, as pink shrump )P. paulensis) an blue Crab (C. sapidus).