Calyx magnoculata, 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 : 425

Calyx magnoculata new species

Figures 16a–e

? Pachypellina podatypa ; sensu Van Soest, 1980: 91, pl. XIV fig. 3, text-fig. 34.

? Calyx cf. podatypa sensu Van Soest & Stentoft, 1988: 133 , text-fig. 65 (not De Laubenfels, 1934: 23)

Material examined. Holotype: RMNH Por. 9254, Caribbean Netherlands, Bonaire (Dive 4), 112.08°N 68.2938°W, depth 232 m, on a limestone rockwall, coll. L.E. Becking & E. Meesters, field nr. BON4/ BDR060 , 1 June 2013.

Description. Massively encrusting sponge ( Fig. 16a ), 11 x 16 cm in lateral expansion, 2 cm thick, provided with two conspicuous flush oscules with thin rims, approximately 1 cm in diameter. Preserved holotype consists of three fragments, the largest of which is 4 x 2 x 2 cm. Surface smooth, but bumpy, irregular with occasional small hillocks. Consistency firm, crumbly. Colour light beige.

Skeleton. Surface skeleton a dense multilayered crust of spicules ( Fig. 16b ) lacking orientation or organization. The layer is approximately 100–150 µm in thickness and on average is 8 spicules thick. It overlies an irregular zone of subdermal spaces ( Fig. 16c ), which are traversed by occasional more or less perpendicularly oriented spicule bundles, which follow an indistinct course in the underlying choanosomal skeleton. The latter is barely reticulate, mostly an isotropic–confused spicule mass, with few larger open spaces.

Spicules. Oxeas.

Oxeas, relatively sharply pointed, slightly curved, apparently in two slightly overlapping size categories, which are, however, not localized in the skeleton and distinguished only in size, (1, Fig. 16d, 16d 1 ) 225– 242 –264 x 10– 11 – 13 µm, and (2, Fig. 16e ) 141– 170 –195 x 6– 8 – 10.5 µm.

Ecology and distribution. Known only from the type locality, a vertical limestone wall at 232 m off SW Bonaire.

Etymology. The name reflects the large conspicuous oscules.

Remarks. The species is assigned to the genus Calyx on account of the thick crust of intercrossing oxeas at the surface, making a characteristic, dense armor. The only other known Western Atlantic Calyx species is C. podatypa ( De Laubenfels, 1934 as Haliclona ). It is largely similar to our new species, but has distinctly smaller spicules, 90–119 x 2–4 µm in the type and its oscules are of the key-hole type, not rounded; color is pinkish beige, not tan like our new species. C. podatypa has also been hesitatingly reported from deep water off Puerto Rico ( Van Soest 1980: 91 as Pachypellina ) and from deep water off Barbados ( van Soest & Stentoft 1988: 133). Both records might possibly belong to the present new species, as the upper size of the spicules nears that of our material and is up to twice the length of those of the type of C. podatypa . The type of the latter has been found between 36 and 72 m depth, but most subsequent specimens originate from shallow water (e.g. Rützler et al. 2014).

Figures

FIGURE 1. Map showing the positions of Bonaire and Klein Curaçao (Southern Caribbean), where the present collections were obtained. Insets show details of locations and course of dives 2–4 of the Curasub.

FIGURE 16. Calyx magnoculata n. sp., holotype RMNH Por. 9254, a. habit shortly after collection, b. dense ectosomal skeleton, d–e. SEM images of spicules, d. larger oxea, d1. detail of apex of larger oxea, e. smaller oxea.