, enteropneusts and metals from two estuarine tidal flats, Pacific, Costa Rica.
Schulze (2008): An updated checklist of the sipunculans
(Phylum Sipuncula) of Cuba.
Historical overviews by Rouse (1999) and Nielsen (2004) identify Hatschek (1878) as the first to propose that a type of feeding trochophore found among extant polychaete annelids typified features of the ancestral larval form for annelids, molluscs, sipunculans
, and echiurans.
Polar Filament-Formers in Tissues of Fish, Sipunculans
, and Annelids)
Taylor also points out that predatory gastropods in eutrophic waters on continental shores tend to be generalist feeders on suspension-feeding barnacles and bivalves, whereas predatory gastropods in oligotrophic waters are more specialized feeders on algal-grazing polychaetes, sipunculans
, or gastropods.
Most species were polychaetes but some hirudineans and sipunculans
were also included; seven genera were proposed and 84 species were newly described.
show a different, nonsegmental formation mode that cannot be explained by the existence of a posterior growth zone.
A group of 15 species included flatworms, nemerteans, two sipunculans
, oligochaetes, two brachiopods, two echinoderms, hemichordates, a lancelet and a gobiid fish (Vargas 1989).
Teleplanic (long-lived) larvae are transported by currents across ocean basins (Hacker, 1898; Mortensen, 1898; Scheltema, 1968, 1988; Laursen, 1981) and have been reported in diverse taxa, including ranellid and architectonicid gastropods (Scheltema, 1966, 1971a, b, 1988; Laursen, 1981; Bieler, 1983; Scheltema and Williams, 1983), bivalves (Gofas, 2000; Scheltema and Williams, 1983), polychaetes (Scheltema, 1974; Murina, 1997), sipunculans
(Scheltema and Rice, 1990; Staton and Rice, 1999), and spiny lobsters (Phillips et al.
The dominant non-colonial macro boring families at the study reefs are mytilid bivalves, eunicid polychaetes and aspidosiphonid sipunculans
, with the bivalves considered the main internal bioeroders due to their greater body size and abundances.
are coelomate nonsegmented marine worms closely related to annelids; however, they lack a true circulatory system (Stephen and Edmonds, 1972; Maxmen et al.
(Rice, 1988), bivalves (Grassle et al.