Swarupella Shrivastava, 1981

Wood, Timothy S., 2022, Phylactolaemate bryozoans at the Zoological Survey of India and a taxonomic key to Indian Phylactolaemata, Zootaxa 5200 (2), pp. 401-435 : 428

Swarupella Shrivastava, 1981

The genus Swarupella was created to accommodate the species S. andamanensis ( Shrivastava, 1981) first collected on the Andaman Islands and later at Motikund, Narsingharh in Madhya Pradesh (Rao 1985). “The chief distinguishing feature of the species is the presence of the diminutive spines at both the extremities (of the floatoblast). Along the suture these spines continue posteriorly as a sutural frill” ( Shrivastava 1981).

Since the discovery of S. andamanensis , sutural spines have been noticed in other species as well, including S. divina Wood, 2006 and S. kasetsartensis Wood, 2006 . Small sutural projections have also been described in Plumatella jariensis Wood & Okamura, 2017 and Plumatella kisalensis Wood, 2020 , although these resemble little knobs rather than spines.

I find that the minute spines in Swarupella species do not dissolve in alkali, suggesting that they are actual extensions of the chitinous periblast and not derived from secondary materials. Unfortunately, their shrinkage and distortion upon drying makes them difficult to examine by traditional scanning electron microscopy. In S. andamanensis the spines appear to be about the same length along the entire suture, but they project outwards more at the sharp curvature at each end of the statoblast.

For now, I consider Swarupella to be an acceptable genus for grouping certain plumatellid species. Whether the genus has any phylogenetic significance is yet to be determined.