Rhabderemia gallica

Van Soest and Hooper, 1993

Species Overview

Rhabderemia gallica Van Soest and Hooper, 1993 is a thinly encrusting sponge of which no further macroscopical details are known. It has distinctive spiculation. Recorded from Roscoff and the Mediterranean.

Taxonomic Description

Colour: Not recorded.
Shape, size, surface and consistency: Encrusting (no further macroscopic details recorded).
Spicules: Megascleres : Rhabdostyles entirely smooth, with compact tightly coiled rhabdose end, (unusually short in the Mediterranean specimens, larger in the Roscoff specimens), sometimes rhabdostyles are deformed into right-angled spicules: 57-102-178 x 4-5 µm; microstyles, rugose, thin, often with small subterminal tyle: 55-70.3-99 x 0.5-1.5 µm.
Microscleres : Thraustosigmas, small, irregularly curved: 17-21 µm.
Skeleton: Ectosomal : Not recorded. Choanosomal : Single megascleres erect on the sub-
strate.
Ecology: At intermediate depths (60 m).
Distribution: Mediterranean-Lusitanian, so far known only from French waters.
Etymology: Gallia is the Roman name for France.
Type specimen information: Holotype in the Paris Museum, MNHN DT 115, Ile Grosse, Banyuls, Mediterranean coast of France; paratype also in the Paris Museum, MNHN DCl. 874, Roscoff, N of Ile de Batz, Atlantic coast of France.

Remarks

The species differs from Caribbean R . minutula s.s. in that it possesses thraustosigmata and relatively small megascleres. It shares these characters with the Indian Ocean species R . burtoni Van Soest and Hooper, 1993 (= R . pusilla sensu Dendy, 1922), from which it differs in the entirely smooth condition of the rhabdostyles and the shorter microstyles (up to 135 µm in R . burtoni ).
From the Mediterranean-Atlantic R . topsenti Van Soest and Hooper, 1993 (= R . minutula sensu Pulitzer-Finali, 1983) the species differs in having thraustosigmata, which are also considerably larger than the small contorted sigmata of R . topsenti , and the larger microstyles.
Source: Van Soest and Hooper, 1993