Hymeniacidon caerulea Pulitzer-Finali, 1986

Ugalde, Diana, Gómez, Patricia & Simões, Nuno, 2015, Marine sponges (Porifera: Demospongiae) from the Gulf of México, new records and redescription of Erylus trisphaerus (de Laubenfels, 1953), Zootaxa 3911 (2), pp. 151-183 : 165-166

Hymeniacidon caerulea Pulitzer-Finali, 1986

( Figs. 11 A–B, 13E)

Selected synonymy: Laxosuberites coerulea sensu de Laubenfels, 1936:148. Hymeniacidon caerulea Pulitzer-Finali, 1986:117 ; Díaz et al. 1993:298.

Material examined. CNPGG –1138 Alacranes reef (22° 22' 1.56”N 89° 40' 30.36”W), depth 6 m, 8/VIII/2009.

Description. Thinly encrusting sponge, 5.7 cm in diameter, and less than 1 mm to 15 mm in thickness (measures out of the water). Oscules are only seen in live specimens, with 2–4 mm in diameter. The sponge surface is smooth in parts and tuberculate or rugose in others, microscopically hispid. Consistency is very compressible and soft. Vivid cobalt blue alive ( Fig. 13 E), still dark blue in alcohol, color has paled but persisted as the time goes by.

Skeleton. Ectosomal skeleton is a conglomerate of tangential spicules. Choanosomal skeleton is halichondroid, with scattered and ill-defined spicule tracts, with single spicules in confusion ( Fig. 11 A).

Spicules. Straight styles, slightly curved towards the middle and third part of shaft, some are flexuous. The spicules are distinguished by an elongated dark spot at the base which is part of the axial canal ( Fig. 11 B), 213–431.6 × 2.3–5.2 µm.

Distribution and ecology. Florida (de Laubenfels 1936); Dominican Republic and Puerto Rico, from 4 to 8 m in depth ( Pulitzer-Finali 1986); Belize, Hispaniola, Curaçao on coral rubble and mangroves, 6–12 m deep ( Rützler et al. 2000). Quintana Roo, Mexico and Puerto Vargas off the coast of Costa Rica. The specimen was collected in coral rubble at 6 m depth. This is the first record for the southern Gulf of Mexico.

Remarks. Hymeniacidon caerulea is a shallow reef sponge, and also been found in fringing mangroves ( Diáz et al. 1993). Authors have recorded tylostyles 315–480 × 2–5 µm (de Laubenfels 1936); styles 230–560 × 4.5–9.5 µm ( Pulitzer-Finali, 1986); styles 420–530 × 7–12 µm ( Díaz et al. 1993). Smaller length sizes were found in the styles of the present material. On the other hand, diameter size is within the reported range, and the cobalt blue color and skeletal arrangement are distinctive traits for this species.

Figures

FIGURE 11. Hymeniacidon caerulea Pulitzer-Finali, 1986: A. Choanosomal arrangement with scattered and ill-defined spicule tracts. B. Common style marked by elongated dark spot or hilum at the tyle, visible in LM.

FIGURE 13. Sponges in situ A. Erylus formosus. B. Cliona amplicavata excavating on Lobatus gigas shell. C. Cliona flavifodina. D. Chondrilla caribensis, E. Hymeniacidon caerulea.