Description. This sponge usually forms cylindrical branches (Fig. 5 A, 5 B), erect or repent (Fig 5 D), solitary or ramified (Fig 5 E); it can also develop oscular lobes or thickly encrusting coats; variable length, 10 – 30 cm, 1 – 3 cm in diameter (Fig 5 C, 5 F). External colour orange to orange yellow; internal colour orange yellow; the colour becomes darker after collection. Its consistency is compressible, flexible and elastic in life or preserved, difficult to tear or cut, but still flexible in dry state. Pinacoderm sustained by tracts of spicules, collapses out of the water revealing subdermal channels (2 – 4 mm wide). Scattered oscules at the same level of the pinacoderm, 3 – 6 mm in diameter, with a membranous ring (Fig 5 A); sometimes the oscules are aligned in the upper part of branches, but this is not a typical feature; small ostia <1 mm are dispersed over the surface. The interior is dense but porous, with tiny channels (<2 mm). The skeletal architecture corresponds to an axial skeleton of loose axial fibres, from which primary fibres radiate to the pinacoderm. Primary fibres, 60 – 100 µm in diameter, cored (1 – 6 spicules per cross section) and echinated; secondary fibres not cored, sparsely echinated, 50 – 80 µm in diameter; tertiary fibres not present. Acanthostyles are slightly to moderately curved; 6 – 8 spines per verticil; length 78 – 249 (137 ± 34.5) µm, width 5 – 18 (9 ± 2.2) µm and 726 (13 ± 3.6) whorls per spicule. Detailed lengths, widths and average number of whorls are shown in Table 2.
Sumber: Reef sponges of the genus Agelas (Porifera: Demospongiae) from the Greater Caribbean