Morphological description (show/hide)
| Massive, sub-cylindrical, vaguely elongate, rounded, bulbous growth form, partially burrowing soft sediments or excavating hard sediments, up to 350mm long, 200mm wide, 160mm thick (although on the Sahul Shelf specimens several metres in diameter were observed). | | Light orange-brown to bright orange exterior | | Texture harsh, firm, spiculose | | Pineapple-like, convoluted, crustose surface, with large conules or rounded or polygonal plates, 18-35mm diameter, slightly raised above surface and separated by shallow but distinct grooves, apex of sponge with irregularly meandering or discrete series of relatively deep, excavated channels (sieve-plates or porocalyces), up to 60mm deep, containing large oscules (up to 50mm diameter) especially near apex of sponge, each oscule with a raised membranous lip. Exterior surface invariably silt covered, interior soft, mango-like.. | | Cavernous, reticulate skeletal structure, with differentiated primary and secondary spongin fibres and spicule tracts, primary, ascending, multispicular fibres (70-250um diameter) more-or-less regularly spaced, 300-650um apart, interconnected by secondary, transverse or oblique, pauci-, uni- or aspicular fibres (30-80um diameter). Fibres lightly or heavily invested with spongin, depending on their thickness, and cored only by larger (choanosomal) oxeas. Fibre meshes evenly rectangular, triangular or irregularly oval, 90-260um diameter, containing abundant collagen, collagenous fibrils, many scattered smaller oxeas, and bundles of raphides. Choanocyte chambers small, oval, 40-70um. | | Distinct, thick, detachable, paratangential crust of smaller (ectosomal) oxeas, 400-850um wide, with innermost layer nearly horizontal and outermost layer nearly perpendicular to the surface, together forming a continuous palisade of spicules. Ectosomal crust supported by long, pillar-like tracts of large oxeas, usually widely spaced (450-780um long, 750-900um apart), producing an excavated subdermal region containing large cavities, about 650um diameter, with sparse collagen, collagenous fibrils, bundles of raphides and sparsely scattered smaller oxeas. | | Two categories of megascleres of similar morphology, clearly distinguished only by size and distribution in skeleton, both entirely smooth, relatively large, straight or slightly curved at centre, rarely asymmetrical, tapering to sharp fusiform points. Smaller (ectosomal) oxeas - length 319-(535.3)-708, width 4-(9.2)-12. Larger (choanosomal) oxeas - length 644-(688.1)-782, width 13-(17.3)-22. | | Raphides rarely seen individually, but more commonly occurring as bundles of hair-like raphides (trichodragmata). Dimensions of bundles up to 140 x 15um. |
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