Gastrophanella cavernicola Muricy & Minervino, 2000

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 : 53-54

Gastrophanella cavernicola Muricy & Minervino, 2000

( Figure 2 c)

Synonymy and references. Gastrophanella implexa Schmidt, 1879 : sensu Macintyre et al., 1982: 134, fig. 83b; Gastrophanella cavernicola Muricy & Minervino, 2000: 600 , figs. 2–5.

Material. USNM 32868, Columbus Cay cave, Belize, 20 m, ceiling, 20 m from entrance; I. G. Macintyre col. 26 Apr 1979. USNM 32871, Columbus Cay cave, Belize, 18–21 m, ceiling; B. Lester col. 24 Apr 1979. USNM 32875, Columbus Cay cave, Belize, 30 m, wall; C. Feller col. 25 Jun 1983.

External morphology. Massive, lobate, up to 20 mm thick and 50 mm in diameter. Single oscula on top, up to 3 mm in diameter, with radiating vein-like canals just below the surface; small patches of ostia in surface depressions and along the sides of specimens. Surface finely rough, consistency hard, color in life cream.

Skeleton structure. In the choanosome there is a dense reticulation of fused desmas, with tylostrongyles mixed in and also radiating toward the surface where they form a disorganized palisade with tyles outward Muricy & Minervino, 2000, fig 3).

Spicules. Monocrepid desmas, 220–360 (280) Μm in diameter; tylostrongyles, 250–480 x 2.5–11.4 (358 x 6.4) Μm (measurements from Muricy & Minervino, 2000, tab. 1, figs 4, 5).

Ecology. In dark areas of caves, 3– 30 m.

Distribution. Northeast Brazil and Belize.

Comments. The “Blue Hole” record from Lighthouse Reef atoll, Belize ( Muricy & Minervino, 2000) is erroneous, due to a misunderstanding. Columbus Cay cave is a drowned karst cave, just like the famous “Blue Hole” of Lighthouse Reef some 60 km east-northeast, but its entrance tunnel on the lagoon floor (see Macintyre et al., 1982) is more like a black crack although local fishermen refer to it as “blue hole.” In Belize, Gastrophanella cavernicola has so far only been recorded from Columbus Cay cave.

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).