Morphological description (show/hide)
Growth form ranges from erect, branching, bulbous, digitate tubes, with several tubes attached to a common base, some bifurcating some single and each terminating with a single osculum (paratype), to irregular more-or-less tubular lobes and low digits arising from a bulbous, thickly encrusting base, with oscules scattered over the apical regions of lobate digits (holotype). Specimens range from about 130mm basal diameter up to encrusting individuals exceeding 320mm basal diameter, and lobate digits range from 20mm long, 25mm diameter, to over 300mm long, 70mm diameter. | Dark orange to pale orange alive (Munsell 10R | Oscular atria surrounded by symmetrical membranous lip. Large openings of excurrent canals (true oscules, 2-5mm diameter) visible inside central oscular atrium. | Prominently conulose, large, bulbous surface tubercles, producing regular (paratype) or irregular (holotype) surface sculpturing. | Skeletal structure plumoreticulate, with differentiated primary and secondary skeletal lines. Primary fibres long, ascending, 50-70um diameter, paucispicular, with never more than 4-5 spicules abreast, secondary fibres shorter, 15-30um diameter, transverse, connecting primary fibres, uni- or aspicular. Primary fibres cored predominantly by principal spicules but also with moderate quantities of longer, more slender auxiliary megascleres interdispersed, spicules in primary fibres occupy only small proportion of fibre diameter. Echinating styles moderately common on primary ascending fibres, sparse on secondary connecting fibres, inserted at oblique angles to fibres, this uneven distribution of both coring and echinating spicules gives skeleton an almost plumose appearance. Choanosomal mesohyl contains sparse collagen, fibre meshes widely spaced, 160-350um diameter, choanocyte chambers oval, 35-60um diameter, and small quantities of sand grains scattered between fibre meshes. | membranous, with a sparse, tangential layer of irregularly dispersed subectosomal auxiliary styles and raphidiform spicules, presumably younger forms of these spicules, ectosomal skeleton also contains erect brushes of auxiliary spicules scattered throughout both peripheral and subectosomal regions, generally protruding towards exterior. In peripheral region mesohyl contains moderately light collagen and few small sand particles. | Choanosomal principal styles slender, straight, relatively short, with hastate points and smooth, slightly swollen, subtylote bases (61-(81.6)-97 x 1.6-(2.7)-3.6). Subectosomal auxiliary styles long, slender, straight, with hastate points and smooth, elongated, swollen subtylote bases (138-(159.4)-183 x 0.4-(2.1)-3.5). Echinating styles entirely smooth, short, slender, sharply pointed, with prominent basal constriction (neck), subtylote base and widest just below basal constriction (32-(35.5)-39 x 1.1-(3.1)-5.0). | Isochelae Nil. Toxas abundant, moderately long, ranging from slender to raphidiform, with straight arms and prominent central curve (65-(135.6)-266 x 0.2-(1.1)-1.6). |
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