Antho circonflexa

(Lévi, 1960)

Species Overview

Antho circonflexa (Lévi, 1960) is a thinly encrusting red sponge with a slightly hispid surface. The species was recorded only twice from the W coast of France. It is one of the many red encrusting microcionids which can only be identified by careful microscopic study of the spicules and their arrangement.

Taxonomic Description

Colour: Red.
Shape, size, surface and consistency: Very thin crust with hispid surface. No further information.
Spicules: Megascleres : Ectosomal subtylostyles: 150-400 x 3 µm; principal styles with rugose heads: 150-450 x 10 µm; acanthostyles/strongyles of the basal reticulation, smooth shaft and spined or rugose apices: 80-170 x 6-10 µm; echinating acanthostyles, lightly spined along the shaft, with spined or rugose heads: 80-150 x 8-12 µm. Microscleres : Palmate isochelae, of which part have a twisted shaft (opposite alae align the shaft at different angles): 10-18 µm; toxas, short, with shallow curve and the median part thickened: 25-85 µm.
Skeleton: "Typical for the genus", i.e. presumably with a basal reticulation of short acanthostyles/ acanthostrongyles, echinated at the nodes by short acanthostyles; long styles are erect on the basal reticulation and project beyond the surface; bundles of subtylostyles and loose subtylostyles are found at the surface.
Ecology: Vertical cliffs, 25 m.
Distribution: Bretagne: Rade de Brest (Cormorandière).
Etymology: The name refers to the twisted chelae.
Type specimen information: The type is in the Muséum Nationale d'Histoire Naturelle, Paris.

Remarks

The twisted chelae and centrally thickened toxas are unique among Antho species of the area.
Source: Lévi, 1960.