Calthropella Calthropella xavierae, Van Soest, Rob W. M., Beglinger, Elly J. & De Voogd, Nicole J., 2010

Van Soest, Rob W. M., Beglinger, Elly J. & De Voogd, Nicole J., 2010, Skeletons in confusion: a review of astrophorid sponges with (dicho-) calthrops as structural megascleres (Porifera, Demospongiae, Astrophorida), ZooKeys 68, pp. 1-88 : 54-56

Calthropella Calthropella xavierae sp. n. Figs 27 A–G

Material examined.

Holotype ZMA Por. 11376, Indonesia, E of Komodo, 8.4867°S; 119.6167°E, depth 138 m, dredge, coll. R.W.M. Van Soest, Snellius II Exped. Stat. 095, 19 September 1984.

Description.

Lobate mass (Fig. 27A), size 6 ×5× 5cm, microhispid surface, rough to the touch. Colour pinkish brown. Two oscule type openings are located on the rounded upper surface, 3-4 mm in diameter. Consistency hard.

Skeleton: a dense crust of asterose microscleres at the surface covers a dense mass of calthrops. Asters are also crowded in the choanosome. The skeleton is densely confused and there are few canals or cavities; some broken monaxone spicules were present.

Spicules: calthrops, globular tuberculate asters, oxyspherasters, oxeas?.

Calthrops (Fig. 27B) in an extremely wide range of sizes and shapes, cladi 44 –238.2– 587 × 5 –40.8– 101 µm, cladome 62 –344.3– 820 µm.

Broken monaxonic spicules (oxeas?) measured up to 700 × 10 µm.

Oxyasters (Fig. 27C), with a discrete rounded center and rays often ill developed or partly missing, range from 8 to 21, possibly in two size categories, the larger (Fig. 27D) with fewer rays, 15 –16.9– 21 (8 rays) and smaller (Fig. 27E) with more numerous rays, 8 –9.7– 10 µm (12-14 rays), but some overlap is present.

Globular tuberculated spherasters (Fig. 27C) or 'silica balls’, appearing to be derived from the normal euasters by heavy silicification, in a wide size range, 6-27 µm, possibly in two size categories, larger (Fig. 27F) 18 –21.3– 27 µm and smaller (Fig. 27G) 6 –8.3– 10 µm.

Etymology.

The name of the new species acknowledges all the help we received from Joana B.R.T. Xavier during her stay in Amsterdam, and the generous donation of several sponge fragments important for this study.

Habitat.

Dredged from hard bottom at 138 m.

Distribution.

Known only from the type locality, E of the island of Komodo, Nusa Tengara (southern island chain bordering the Banda Sea).

Remarks.

This is a clear Calthropella (Calthropella) resembling the type species Calthropella (Calthropella) simplex in all but the finer details of spicule sizes and shapes. The habitus is more elaborately globular and has pinkish brown colour (in alcohol) in contrast to more flattened pale yellow–grey Calthropella (Calthropella) simplex ; there appear to be two distinct size categories of oxyspherasters in the new species.

No matching descriptions are found in the Indo–West Pacific region, but Topsent (1897) reported the occurrence of Calthropella geodioides var. from Ambon Bay, Indonesia (see also below based on a redescription in Desqueyroux-Faúndez 1981) which shows a few similarities. It differs from our new species at least by the possession of dichocalthrops, apparently proper oxeas and white colour.