Morphological description (show/hide)
| Lamellate, massive, mostly planar growth form, with or without basal attachment, consisting of more-or-less fused erect thin digits forming a continuous lamella, 370 mm maximum span, with some free or barely anastomosing sections. Lamellae are 116-135 mm high, 4.5-7 mm thick, forming irregular meshes between branch anastomoses, 3-14 mm diameter. | | Live colouration was salmon-pink (Munsell 5RP | | Oscules were not observed, and ostial pores are minute and scattered over the surface, 0.5-1 mm in diameter. | | Texture is firm but compressible and difficult to tear. | | Lamellae are prominently longitudinally striated with ridges, grooves and discontinuous conulose projections, and margins of lamellae are digitate and microconulose. | | Choanosomal skeletal architecture is irregularly reticulate, without axial or extra-axial differentiation. Fibres are relatively heavy, imperfectly separated into primary and secondary elements, and form ovoid to elongate, relatively cavernous meshes 140-680 ï¾µm wide. Primary fibres, 92-165 ï¾µm diameter, are cored by multispicular tracts of choanosomal principal styles which occupy approximately 3/4 of fibre diameter. Secondary fibres are uni- to paucispicular, 26-71 ï¾µm in diameter. All fibres are relatively heavily echinated by acanthostyles, which protrude from fibres at various angles. The mesohyl matrix contains abundant, lightly pigmented, slightly granular spongin, abundantly cored by subectosomal megascleres, which may completely obscure skeletal architecture in places. Choanocyte chambers are oval, 42-68 ï¾µm in diameter. | | Ectosomal skeleton consists of a relatively thin but dense crust, 60-95 ï¾µm thick, composed of erect ectosomal auxiliary subtylostyles forming a continuous dermal palisade. Immediately below and protruding into the dermal skelton is a mostly paratangential layer of subectosomal auxiliary subtylostyles. In thicker, more elongated sections those megascleres may form plumose ascending tracts supporting the dermal skeleton, but mostly they lie paratangential to the surface, arising from the peripheral choanosomal fibres. Subectosomal region is relatively cavernous. In young sections of the peripheral skeleton, elongate conulose protrusions may extend a long way from the surface, fully cored by dense tracts of subectosomal subtylostyles. | | Choanosomal principal styles are fusiform, thick, slightly curved towards the basal end, with rounded or very slightly subtylote and smooth bases. Length 166-(185.5)-218 ï¾µm, width 7.5-(12.6)-16 ï¾µm. Subectosomal auxiliary subtylostyles are long, thick, straight or slightly curved, fusiform, with slightly subtylote or rounded and microspined bases. Length 134.6-(218.8)-286 ï¾µm, width 3.5-(6.5)-8.6 ï¾µm. Ectosomal auxiliary subtylostyles are straight, fusiform, thin, with more prominent and invariably microspined subtylote bases. Length 86-(97.6)-114.5 ï¾µm, width 2.5-(3.3)-4.5 ï¾µm. Acanthostyles are thick, straight, with slightly subtylote or rounded bases, and large spines dispersed over apical and basal extremities, usually with an aspinose neck but occasionally evenly spinose. Length 67-(79.8)-92.5 ï¾µm, width 3.8-(8.6)-11.6 ï¾µm. | | Palmate isochelae are divided into two size classes, both unmodified and relatively small, and both moderately uncommon. Length I 9.1-(10.9)-14.8 ï¾µm, length II 2.7-(4.4)-8.2 ï¾µm. Toxas are thin, rhaphidiform, varying from small forms with slightly curved centres and slightly reflexed points, to long forms with only very slightly rounded central curvature and straight or slightly reflexed points, no sinuous forms were seen. Length 11-(121.1)-166 ï¾µm, width 0.4-(0.8)-1.2 ï¾µm. |
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