Sponges of the Guyana Shelf Author Van, Rob W. M. text Zootaxa 2017 1 1 225 journal article 37320 10.5281/zenodo.272951 e2c88f4c-3ac2-45f9-95e4-99b75561a081 1175-5326 272951 6D68A019-6F63-4AA4-A8B3-92D351F1F69B Haliclona (Reniera) cf. implexiformis ( Hechtel, 1965 ) Figures 18 a–c Restricted synonymy: Adocia implexiformis Hechtel, 1965 : 27 , pl. II fig. 2, text-fig. 2. Haliclona (Reniera) implexiformis ; De Weerdt 2000 : 17 , figs 3M, 6A–D (with further synonyms). FIGURE 18 . Haliclona (Haliclona) cf. implexiformis (Hechtel, 1965) , a, habitus of RMNH Por. 9989 (scale bar = 1 cm), a1, of RMNH Por. 9835 (scale bar = 1 cm), b–b1, light microscopic images of skeleton, b, b, surface skeleton, b1, cross section, c, SEM images of oxeas. Material examined. RMNH Por. 9835, Guyana , ‘Luymes’ Guyana Shelf Expedition, station 87, 7.5667°N 57.2667°W , depth 59 m , bottom sand and shells, 2 September 1970 ; RMNH Por. 9989, Suriname , ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station F40, 7.0033°N 56.4417°W , depth 59 m , bottom sand, 6 May 1966 . Description. Irregular masses of lobes and short branches ( Figs 18 a,a1), provided with several prominent, flush oscules. Size of largest mass about 6 x 5 cm, individual branches 0.7–1 cm diameter, lobes up to 1.5 x 1.5 cm , oscules 2–4 mm in diameter. Surface strongly punctate, rather irregular, shaggy (preserved specimens). Color (in alcohol) beige-brown. Consistency soft, limp. Skeleton. Unispicular, both ectosomal ( Fig. 18 b) and choanosomal ( Fig. 18 b1). Occasional paucispicular tracts. Some binding spongin present, but not obvious. Spicules. Oxeas only. Oxeas ( Figs 18 c,c1), straight or lightly curved, fat or more slim, sharply pointed, 96– 114 –135 x 4 – 5.9 –8.5 µm. Distribution and ecology. Guyana Shelf, widespread throughout the Greater Caribbean, from shallow-water down to 59 m depth (previously down to 25 m ). Remarks. The identification of this material (two samples) is uncertain, but if correct it concerns a depth record for the species (previously reported down to 25 m depth). The specimens share with Haliclona (R.) implexiformis the irregular shape, punctate surface, soft consistency, unispicular skeleton and the relatively short oxeas. However, the oxeas especially of specimen Por. 9989 are considerably shorter (96–111 µm) than the specimens reviewed by De Weerdt (2000) , given as 95– 131 –167 µm based on examination of a large number of individuals. No further matching descriptions are found in De Weerdt’s monograph.