Neopetrosia ovata, Van Soest & Meesters & Becking, 2014

Van Soest, Rob W. M., Meesters, Erik H. W. G. & Becking, Leontine E., 2014, Deep-water sponges (Porifera) from Bonaire and Klein Curaçao, Southern Caribbean, Zootaxa 3878 (5), pp. 401-443 : 427-429

Neopetrosia ovata new species

Figures 18a–f

Material examined. Holotype: RMNH Por. 9257, Caribbean Netherlands, Klein Curacao, off SW coast (Dive 1), 11.9821°N 68.6452°W, in the sand at 149 m, coll. L.E. Becking & E. Meesters, field nr. CURASUB13-09/ BDR002 , 27 May 2013.

Description. Pinkish beige, ovate sponge ( Figs. 18a–b ), size 10 cm high, 8 cm in diameter, with a central oscule of 1.4 cm in diameter. The preserved holotype consists of three fragments the largest of which is 3.5 x 3 x 2 cm. Surface smooth, punctate in life, covered with tiny zoanthids. Oscule rim thin, slightly raised. Inner side of atrial lumen ridged lengthwise. Consistency firm to hard.

Skeleton ( Figs. 18e–f ). Dense mass of oxeas forming vague rounded meshes, which are largely obscured by the thick tracts. Compared to the skeleton of N. dutchi n. sp. described above, the present skeleton is much less organized and much more confused.

Spicules. Oxeas.

Oxeas ( Figs. 18c–d ), smooth, robust, slightly curved, uniform in length, but variable in thickness, 200– 235– 270 x 10.5– 14.5 – 15 µm.

Ecology and distribution. In the sand at 149 m depth, at Klein Curaçao.

Etymology. The name refers to the characteristic shape of the sponge.

Remarks. Although spicule sizes and shapes are essentially the same as the above N. dutchi n. sp. the present new species differs clearly from it in the habit (a single upright globular mass vs. a mass of coalescing lobes in N. dutchi n. sp.) and especially also the structure of the skeleton which is much denser and irregular with barely distinguishable meshes. In that respect it somewhat resembles Neopetrosia proxima ( Duchassaing & Michelotti, 1864) but in that species all the spicules are smaller than 200 µm, and its habit is encrusting with oscules raised on small lobes (see redescription in Zea 1987).

Figures

FIGURE 18. Neopetrosia ovata n. sp., holotype RMNH Por. 9257, a. habit in situ, b. habit shortly after collecting, c–d. SEM images of the spicules, c. robust oxea, c1. detail of apex of robust oxea, d. thinner oxea, e. tangential view of ectosome, f. cross section of peripheral skeleton.