Hydroids (Cnidaria, Hydrozoa) collected on the inner continental shelf of the state of Rio de Janeiro, Brazil, during the Oceanographic Operations GEOCOSTA RIO I and II

Abstract

The Brazilian Navy (DHN/MB) commissioned a series of Oceanographic Operations covering almost the entire inner continental shelf of the country from the 1960s through the 1980s. Surveys provided geological data on the sea bottom and marine biota along the entire Brazilian coast. This report lists data on 15 hydroid species collected during Operations GEOCOSTA RIO I in 1979 and GEOCOSTA RIO II in 1986, at depths ranging from 25 to 89 m. Hydroids were obtained at two of 65 stations in Operation GEOCOSTA RIO I, each represented by one species: Aglaophenia rhynchocarpa Allman, 1877 and Plumularia strobilophora Billard, 1913. In Operation GEOCOSTA RIO II, hydroids were present at four of the 25 sampled stations. Fourteen species were recorded: Pennaria disticha Goldfuss, 1820, Tubulariidae mt.1, Filifera mt.1, Filifera mt.2, Bougainvilliidae mt.1, Bimeria vestita Wright, 1859, Plumularia strobilophora Billard, 1913, Amphisbetia operculata (Linnaeus, 1758), Dynamena dalmasi (Versluys, 1899), Sertularella tenella (Alder, 1857), Campanularia hincksii Alder, 1856, Clytia gracilis (M. Sars, 1850), Clytia paulensis (Vanhöffen, 1910), and Orthopyxis integra (Macgillivray, 1842). The ranges of three species (Aglaophenia rhynchocarpa, Plumularia strobilophora, Clytia paulensis) were extended southwards along the Brazilian coast. The bathymetric distributions of six species (B. vestita, P. strobilophora, C. hincksii, C. paulensis, D. dalmasi, O. integra) were also extended on the Brazilian continental shelf.