Arcovestia, Southward and Galkin, 1997

Southward, Eve C., Schulze, Anja & Tunnicliffe, Verena, 2002, Vestimentiferans (Pogonophora) in the Paci c and Indian Oceans: a new genus from Lihir Island (Papua New Guinea) and the Java Trench, with the rst report of Arcovestia ivanovi from the North Fiji Basin, Journal of Natural History 36 (10), pp. 1179-1197 : 1193

Genus ARCOVESTIA Southward and Galkin, 1997 Arcovestia ivanovi Southward and Galkin, 1997

Material

Cruise SO-134 to the North Fiji Basin: sample 33 GTVA, 16ss59¾27.24 ² S, 173ss55¾00.96 ² E; depth 1996 m; TV grab, many juveniles; sample 35 GTVA; 16ss59¾25.56 ² S; 173ss54¾49.14 ² E; depth 2002 m; TV grab; many tube fragments, about 12 occupied; sample 99 GTVA, 16ss59¾29.16 ² S; 173ss54¾54.60 ² E; depth 1999 m; TV grab, several tube fragments, two occupied.

Description

Tubes sinuous, bases attached to fragments of basalt. Diameter 0.6–1.3 mm, colour pinkish, semi-transparent, with narrow, slanting collars. Animals with obturaculum narrow, unadorned, shorter than plume of branchial laments.

Comments

There is no obvious diOEerence, except in size, between these Fiji Basin specimens and those from the Manus Basin. The type material, from the western basin, had a maximum tube diameter of 4 mm ( Southward and Galkin, 1997). Even larger specimens, 7–8 mm tube diameter, were collected in 1996 and 1998 at the DESMOS site in the eastern Manus Basin (courtesy of Jun Hashimoto of the Marine Ecosystems Research Department, JAMSTEC, Japan; for description of the site see Hashimoto et al., 1999).

The ecology of hydrothermal vents in the Fiji Basin was described by Desbruyères et al. (1994). One site, ‘White Lady’, had hot vents with associations of gastropods and mussels, while vestimentiferans were seen only at ‘Mussel Valley’ some distance to the south, cooler, and at a greater depth (18ss49¾S, 173ss29¾E, 2700 m depth). Whether or not these were Arcovestia is unknown. The present Arcovestia ivanovi were collected in the vicinity of the ‘White Lady’ site. The Fiji Basin is some 2500 km east of the Manus Basin, and the only intermediate hydrothermal site is the Woodlark Basin, which has not yet yielded any hydrothermal fauna. A nities among the Manus, Fiji and Lau Basin hydrothermal faunas have been noted in other animal groups ( Galkin, 1992; Hashimoto et al., 1999).