Many coastal habitats are being substantially altered by introduced plants. In San Francisco Bay, California, USA, a hybrid form of the eastern cordgrass Spartina alterniflora is rapidly invading open mudflats in southern and central sections of the Bay, altering habitat, reducing macrofaunal densities, and shifting species composition. The invasion has resulted in significant losses of surface...

Trends among major metazoan meiofaunal taxa were investigated based on 56 deployments of a multicorer at 10 time points over a period of eleven years (1989-99) at a site on the Porcupine Abyssal Plain Sustained Observatory (PAP-SO: 48°50 ́N 16°30 ́W, 4850 m depth). This area is characterised by a strong seasonality in the deposition of organic matter to the seafloor and by the massive increase in...

Five species of polychaetes (Spionidae) were found associated to Thalassia testudinum meadows in Parque Nacional Morrocoy, Venezuela. We included a guide for their identification and present range extensions for the Venezuelan coasts and Southern Caribbean Sea. The species are: Dipolydora socialis, Prionospio (Minuspio) cirrifera, P. (Prionospio) fallax, P. (P.) steenstrupi, and Spio pettiboneae.

A new tunicate, Ascidia subterranea sp. nov., was found in burrows of the axiid crustacean Axiopsis serratifrons on Derawan Island, Indonesia. It differs from other ascidians in its habitat as well as numerous morphological peculiarities which are described in detail. The shrimp Rostronia stylirostris Holthuis, 1952 was found inside A. subterranea sp. nov., and 4 species of bivalves, 3 species ...