Marine Species Identification Portal : Hamacantha papillata

Vosmaer, 1885

Species Overview

Hamacantha (Hamacantha) papillata Vosmaer (1885) is a brownish, cushion-shaped sponge with characteristic high, cone-shape papillae which are lighter coloured at their summit. The genus Hamacantha has characteristic microscleres (diancistras); the present species may be distinguished from the two other Hamacantha species from the area by its possession of only a single size category of diancistras.

Taxonomic Description

Colour: Greyish brown, with lighter coloured papillae.
Shape, size, surface and consistency: Cushion-shaped with irregular surface bearing numerous high, conical papillae with lighter coloured summits. Oscules on some of the papillae. Size up to 4.5 cm in widest expansion. Inside clathrous, with many hollows and canals. Consistency fragile.
Spicules: (Hamacantha papillata spics) Megascleres: Styles: 270-468.6-702 x 6.6-11.4-19.3 µm. Microscleres: Diancistras: 175-188.6-217 x 5.5-10.5 µm; trichodragmas 132 x 64 µm; individual rhaphides 104-120 x 1 µm.
Skeleton: Ectosomal: a crust of tangentially arranged megascleres, some are obliquely piercing the membrane and cause a fine hispidity. Choanosomal: plumose, with irregular multispicular tracts of spicules; many loose single spicules; no spongin.
Ecology: Deep-water down to 1420 m.
Distribution: Arctic, Greenland, Iceland, Norway; also Azores.
Type specimen information: Holotype ZMA POR. 1300, collected by the Willem Barents Exped. to the Barents Sea.

Remarks

Hajdu (1994) compared the holotype with Lundbeck's (1902) Hamacantha implicans and concluded that both were synonymous.
Hamacantha with its characteristic diancistras is represented by three species in the area. H. (Vomerula) falcula has toxas; H. (Hamacantha) johnsoni has oxeas as megascleres. Both lack the trichodragmas and have at least two size categories of diancistras, whereas H. (H.) papillata has only a single size.
Source: Arndt, 1935.

Hamacantha papillata