Iotrochota birotulata ( Higgin, 1877 )

Rützler, Klaus, Piantoni, Carla, Van, Rob W. M. & Díaz, Cristina, 2014, Diversity of sponges (Porifera) from cryptic habitats on the Belize barrier reef near Carrie Bow Cay, Zootaxa 3805 (1), pp. 1-129 : 66-67

Iotrochota birotulata ( Higgin, 1877)

Synonymy and references. Iotrochota birotulata ( Higgin, 1877) : Rützler et al. (2007): 175, fig. 1–3.

Material. USNM 1229062, Carrie Bow Cay, under concrete dock, 0.5–1; K. Ruetzler, col. 17 Jun 1977. USNM 1229063, Carrie Bow Cay forereef cave wall, 25 m; M. C. Diaz col. 8 Sep 2009. USNM 1229064, Curlew Bank forereef cave, 18 m; C. Piantoni and M. Parrish col. 25 Aug 2012.

External morphology. Thickly encrusting (50 cm 2, 15 mm thick) or stout, creeping branches (12 cm long, 1.5 cm diameter, average), with corrugated, finely conulose surface and a few scattered oscula (> 2 mm). Consistency stiff but elastic, difficult to tear. Color in life dark greenish to brown, golden brown when growing in very dark habitats; turning dark purple in alcohol and secreting a purplish mucus when squeezed.

Skeleton structure. A meshwork of spongin fibers, 200–400 Μm thick, packed with spicules, the primary tracts ending in the surface conules.

Spicules. The fibers are filled with straight or slightly bent strongyles, mixed with a few stout styles (styles I). Interstitial spicules are thin styles (styles II, quite rare) and birotules. Strongyles: 94–256 x 3–7 (172 x 6) Μm; styles I (n=5): 153–175 x 5–8 (161 x 7) Μm; styles II (n=5): 200–154 x 3–5 (230 x 4) Μm; birotules, length: 14–16 (15) Μm.

Ecology. Occurs on the shallow, open reef, cryptic under rocks and in caves, 0.5– 65 m. One cave specimen was almost entirely overgrown by another sponge, Ectyoplasia ferox .

Distribution. Gulf of Mexico, Caribbean, and northeastern Brazil..