Mycale (Aegogropila) pachysigmata Pulitzer-Finali, 1996

Van, Rob W. M., Aryasari, Ratih & De, Nicole J., 2021, Mycale species of the tropical Indo-West Pacific (Porifera, Demospongiae, Poecilosclerida), Zootaxa 4912 (1), pp. 1-212 : 31

Mycale (Aegogropila) pachysigmata Pulitzer-Finali, 1996

Mycale (Aegagropila) pachysigmata Pulitzer-Finali, 1996: 117 , fig. 16.

Summary description (from Pulitzer-Finali 1996). Thinly encrusting sponge, green in life, white in alcohol. Tangential ectosomal skeleton of aegagropila-type, detachable, strongly developed, tracts stated to be 450–1000 µm in diameter, delimiting meshes of 1800–2800 µm wide. If this is accurate, then this makes the sponge unique among all species of the subgenus. Choanosomal skeleton not described. No mention is made of rosettes. Spicules mycalostyles, robust, 450–550 x 7–15 µm, anisochelae I of ‘normal’ shape, 40–48 µm, anisochelae II 18.5–23 µm, anisochelae III 11.5–13.5 µm, sigmas in two categories, one with thickness 3.4–4.5 µm and length 70–85 µm the other, more rare, category has a thickness of 11.5–14 µm, length 90 µm.

Distribution. Laing Island, N Papua New Guinea, depth 1 m.

Comment. As stated above, the species appears close to M. (Ae.) gravelyi , but the extreme thickness of sigmas and ectosomal tracts, precludes synonymy of the two. Re-examination of the type material in the Genoa museum is warranted, also because description of the choanosomal skeleton is lacking and the precise shapes of the anisochelae are unknown.