Aiolochroia crassa ( Hyatt, 1875 )

Van, Rob W. M., 2017, Sponges of the Guyana Shelf, Zootaxa 1, pp. 1-225 : 16

Aiolochroia crassa ( Hyatt, 1875)

Figures 7 a–b

Restricted synonymy:

Dendrospongia crassa Hyatt, 1875: 401 , pl. 13 figs 1–2, 7.

Pseudoceratina crassa ; Bergquist 1980: 494.

Aiolochroia crassa ; Wiedenmayer 1977: 75 (with additional synonyms); Van Soest 1978: 65, pl. XIII fig. 3, text-fig. 21; Muricy et al. 2011: 171; Moraes 2011: 219; Hajdu et al. 2011: 221.

Material examined. RMNH Por. 9819, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 107, 7.7°N 57.5°W, depth 65 m, muddy sand bottom with shells, 5 September 1970 .

Description. Large specimen ( Fig. 7 a), cake-shaped, 19 x 11 x 6 cm, with conulose surface. No visible openings. Discolored partially to blackish purple, partially beige-colored. On-deck photos from CREOCEAN specimens were bright yellow, showing incipient discoloration to dark purple at their conules. Consistency toughly compressible.

Skeleton. ( Fig. 7 b) Spongin fibers anastomose infrequently to form irregularly elongate meshes of 2 mm or larger in size. Thickness of the fibers variably 90–400 µm, with pith occupying most of the diameter, with thin bark occupying 15–30 %.

Distribution and ecology. Guyana Shelf, throughout the Greater Caribbean, and North East Brazil, on reefs and other hard substratums, shallow water down to 100 m. Guyanan material was from 65 m depth, French Guyanan material collected by the CREOCEAN expedition was obtained at 83 m

Remarks. The specimen conforms in all aspects to the descriptions of previous authors. Although the species has been reported predominantly from shallow-water reef environments, there are several deep-water records (cf. Muricy et al. 2011).

I report here the occurrence of several purplish black patches of an encrusting verongid, which possibly might belong to Vansoestia caribensis Díaz, Thacker, Redmond, Pérez & Collins, 2015 . The material is registered as RMNH Por. 9792 ( Guyana, ‘Luymes’ Guyana Shelf Expedition, station 51, 7.6833°N 57.0333°W, depth 98 m, bottom calcareous sand, 30 August 1970) . It consists of irregular encrustations on carbonate rubble, lateral size about 2 x 3 cm. Thickness up to 2 mm. Surface peels are striated, rather parchment-like, thin. Consistency soft. No skeleton, no discrete fibers. The material is not certainly identified, due to the fact that no histology could be performed, which is the only certain way to identify the genus Vansoestia . The association with Vansoestia is here made on the basis of the absence of any discrete skeleton, but thin incipient Aiolochroia crassa may likely be indistinguishable.

Figures

FIGURE 7. Aiolochroia crassa (Hyatt, 1875), RMNH Por. 9819, a, habitus (scale bar = 1 cm), b, light microscopic image of skeleton of pithed fibers.