Clathria (Thalysias) curacaoensis Arndt, 1927

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 : 61-62

Clathria (Thalysias) curacaoensis Arndt, 1927

( Figures 2 a, 35)

Synonymy and references. Aulospongus schoenus de Laubenfels, 1936b: 100, pl. 13 (3); Raphidophlus schoenus (de Laubenfels, 1936): van Soest (1984a): 112, fig. 44.

Material. USNM 1229011, Carrie Bow Cay, inner reef slope, cave ceiling, 18 m; K. Ruetzler col. 14 May 1975. USNM 1229012, Carrie Bow Cay lagoon, under concrete dock, 1 m; K. Ruetzler col. 17 Jun 1977. USNM 1229013, Carrie Bow Cay lagoon, lower surface of coral plate. K. Ruetzler col. 8 May 2007. USNM 1229014, Carrie Bow Cay lagoon, under concrete dock, 1 m; K. Ruetzler col. 3 July 2007. USNM 1229015, 1229016, 1229017, 1229018, Carrie Bow Cay South reef, lower surface of rock slab, 1 m; K.Ruetzler col. 13 Mar 0 9.

External morphology. Thinly encrusting 4–60 cm 2 areas; dry feeling (non-mucous). Live color is deep red, dull red, greenish orange to ochre.

Skeleton structure. Interconnected spicule tracts (including styles and tylostyles), ending in reticulation and some brushes at the sponge surface. Acanthostyles occur mainly near the base.

Spicules. Styles, many subtylote: 220–360 x 5–9 (324 x 7) Μm; (sub-)tylostyles I (some with microspined heads): 220–330 x 3–4 (262 x 4) Μm; (sub-)tylostyles II: 80–160 x 2–3 (122 x 2) Μm some with microspined heads); acanthostyles: 38– 60 x 5–10 (48 x 6) Μm; regular toxas: 45–100 (67) Μm, all about 1 Μm thick; rhaphidiform toxas: 200–275 (160) Μm, all <1–1 Μm thick; palmate isochaelas in two size categories, I: 8–13 (12) Μm and II: 3–8 (5) Μm, the latter mostly twisted.

Ecology. Common on the lower surfaces of coral rubble; also found on concrete pillars under a boat dock, and on the ceiling of a small cave on the forereef; 1– 18 m.

Distribution. Forida, Bahamas, Gulf of Mexico, and throughout the Caribbean.

Comments. Lobate, ramose, and flabellate specimens are known from non-cryptic habitats in mangroves and on reefs (van Soest, 1984a). The synonymy of this species has been clarified in a recent revision by van Soest et al. (2013a).

Figures

FIGURE 2. The most common cryptic habitats studied in the Carrie Bow Cay vicinity (measurements in parentheses are picture widths): a, lower surface of platy coral rock showing the characteristic red foraminiferan Homotrema rubrum, calcareous serpulid polychaete tubes, and two encrusting sponges, Clathria (Thalysias) venosa (left) and Clathria (Thalysias) curacaoensis (10 cm); b, wall inside a forereef framework cave, showing the massive Smenospongia cf. echina (yellow) and Topsentia bahamensis, and encrusting Clathria (Microciona) bulbotoxa (17 cm); c, ceiling of the drowned karst cave in the barrier reef lagoon near Columbus Cay, about 20 m away from the entrance (“ blue hole ”), showing cemented (mostly dead) serpulid tubes, a branching form of Geodia gibberosa (center) and a few knobby specimens of Gastrophanella cavernicola (far left and right; 20 cm); d, broken-up rock from a forereef cave bottom, showing deserted polychaete borings that are colonized by Cryptosyringa membranophila specimens (6 cm); e, broken-up coral rock showing chambers of excavating sponge Cliona cf. mucronata (7 cm); f, Queen conch (Strombus gigas) shell discarded by local fishermen are a common cryptic habitat on the shallow reef (the slot cut by machete near the apex (arrow) to remove the conch assures good ventilation inside the shell); this shell is colonized outside by Chondrilla caribensis, which occurs fully light exposed as well as in darkness (20 cm); g, peat cave (undercut) in the Twin Cays mangrove, the wall covered by Scopalina ruetzleri (80 cm).