Pseudotrachya amaza ( De Laubenfels, 1934 )

Van, Rob W. M., 2017, Sponges of the Guyana Shelf, Zootaxa 1, pp. 1-225 : 122-123

Pseudotrachya amaza ( De Laubenfels, 1934)

Figures 75 a–d

Anomolissa amaza De Laubenfels, 1934: 17 .

Pseudotrachya hystrix sensu Van Soest & Stentoft 1988: 79 , pl. X fig. 1, text-fig. 38. (not: Trachya hystrix Topsent, 1892a ) Pseudotrachya amaza ; Lehnert & Van Soest 1999: 149, fig. 19; Boury-Esnault 2002: 218.

Material examined. RMNH Por. 9806, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 65, 7.55°N 57.0833°W, depth 63 m, sandy bottom, 31 August 1970 ; RMNH Por. 9991, Suriname, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station E66, 7.1°N 56.1783°W, depth 65 m, Agassiz trawl, 13 May 1966 .

Description. ( Fig. 75 a) Coarse, irregular massive to digitate sponges, with microconulose, hispid, faintly grooved surface. Several oscules are visible, approximately 3 mm in diameter. Size of largest specimen 8 x 4.5 x 4 cm. Color orange-brown in alcohol. Consistency firm.

Skeleton. Cortical-radiate, with 300–500 µm wide bundles of large styles traversing the choanosome and fanning out near the surface, carrying a dense 200 µm thick cortical palisade of small oxeas. Individual long styles penetrating up to 500 µm beyond the surface.

Spicules. ( Figs 75 b–d) Long and short styles/anisoxeas, oxeas.

Styles/anisoxeas, fusiform, with narrow rounded base and abruptly pointed ends, divided into two more or less distinct but slightly overlapping size categories, (1) larger ( Figs 75 b,b1), 1122– 1661 – 2298 x 28 – 41.5 –54 µm, and (2) smaller ( Figs 75 c,c1), 498– 663 –990 x 11 – 17.1 –26 µm.

Oxeas ( Figs 75 d), straight, sharply pointed, 102– 150 –198 x 3 – 4.8 –6 µm.

Distribution and ecology. Guyana Shelf, Puerto Rico, Barbados, Jamaica, sandy bottom at 25–100 m depth ( Guyana Shelf 63–65 m).

Remarks. The present specimens conform closely to previous descriptions. The larger stylote spicules are called oxeas or strongyloxeas by previous authors, because of their fusiform shape, but all are similar. The size categories in these spicules distinguished here are not mentioned by previous authors, but the overall range conforms closely in all descriptions.

Figures

FIGURE 75. Pseudotrachya amaza (De Laubenfels, 1934), a, habitus of RMNH Por. 9806 (scale bar = 1 cm), b – d, SEM images of spicules, b, style, b 1, details of b, c, small style, c 1, details of c, d, oxeas.