Strepsichordaia, BERGQUIST ET AL., 1988

Wahab, Muhammad Azmi Abdul, Wilson, Nerida G., Prada, Diana, Gomez, Oliver & Fromont, Jane, 2021, Molecular and morphological assessment of tropical sponges in the subfamily Phyllospongiinae, with the descriptions of two new species, Zoological Journal of the Linnean Society 193, pp. 319-355 : 347

GENUS STREPSICHORDAIA BERGQUIST ET AL., 1988

Type species

Strepsichordaia lendenfeldi Bergquist et al., 1988 : figs 30, 31, 32, by original designation, holotype AM Z5026 .

Diagnosis

Bergquist et al. (1988) described the species Strepsichordaia lendenfeldi as containing sponges that are cup- or fan-shaped, always macroscopically smooth, with a sand-reinforced surface marked by evenly dispersed, small, flush oscules, each surrounded by prominent, superficially extending exhalant canals. This produces a stellate pattern over the otherwise microconulose oscular surface. The poral surface is macroscopically smooth. A thick organized sand cortex is present on both surfaces. The skeleton is irregular with heavily cored primary fibres, simple not fasciculate but branching in irregular fashion. Secondary elements are not distinct from primary fibres in diameter or coring, only in disposition. Uncored, cylindrical tertiary elements dominate the skeleton; they arise from both primary and secondary cored fibres and form a dense mat throughout the sponge. These fibres meander for a considerable distance, without branching, have no fixed orientation with respect to the surface or attachment base, they do not form fascicles and only occasionally interconnect. The sponge texture is firm, flexible and not easily compressible.

Remarks

The primary and secondary fibres are difficult to tell apart and, as mentioned by Bergquist et al. (1988), they are differentiated by orientation. In some of the specimens in this study, the secondary fibres were thinner. The tertiary fibres were not seen to form a pronounced dense mat, rather they formed an open reticulation, but our sections were cut at 90 µm, which are thinner than the hand-cut sections of Bergquist et al. 1988. Perhaps the tertiary fibre density referred to by those authors is not visible in thinner sections. For this reason, the original diagnosis has not been amended.