Echinoderes, Claparede, 1863

Sørensen, Martin V., Gąsiorowski, Ludwik, Randsø, Phillip V., Sánchez, Nuria & Neves, Ricardo C., 2016, First report of kinorhynchs from Singapore, with the description of three new species, Raffles Bulletin of Zoology 64, pp. 3-27 : 20

Echinoderes sp. 2

Material examined. Two specimens of another unknown species, Echinoderes sp. 2, were collected at station SI- 03. One specimen mounted for SEM did not provide any information, whereas the other one mounted for LM ( Fig. 10 F–J) provided fragmentary information. The LM specimen was deposited at the Natural History Museum of Denmark, under catalogue number ZMUC KIN- 856.

Notes on diagnostic characters. Male Echinoderes ( Fig. 10F ) with quite short middorsal spines at least on segments 4, 5 and 6 ( Fig. 10H ). Round middorsal scars on segments 7 and 8 indicate that spines could have been present here as well, although this is uncertain. This also prevents the opportunities for further identification or description. Additional characteristics include laterodorsal tubes on segment 10, lateroventral tubes on segments 2 and 5 ( Fig. 10G, I ), and short lateroventral spines on segments 6 to 9 ( Fig. 10I ). Tergal extensions, with curved external margins, and pointed offset tips at exterior margins ( Fig. 10J ). Glandular cell outlets of type 2 are not present.

The fragmented information about the dorsal spine patterns makes further attempts to identify the species meaningless. The lateral spine pattern, with spine/tubes on segments 5 to 9, is shared with 56 described congeners, and 33 of these also show lateroventral or ventrolateral tubes on segment 2. The very short middorsal spines, combined with the lateral spine pattern show some resemblance with species such as Echinoderes ehlersi Zelinka, 1913 , Echinoderes gerardi Higgins, 1978 , Echinoderes imperforatus Higgins, 1983 , and Echinoderes sensibilis Adrianov et al., 2002 (see Adrianov et al., 2002c), but the long and pointed tergal extensions in the Singapore species ( Fig. 10J ) differ completely from the rather short and well-spaced ones present in these species. Hence, for now, we would expect Echinoderes sp. 2 to represent a new species, but that a formal description would have to wait until more and better material is available.

Figures

Fig. 10. Light micrographs showing overviews and details of trunk morphology in female Echinoderes sp. 1, KIN-855 (A–E) and male Echinoderes sp. 2, KIN-856 (F–J). A, ventral overview. B, Neck region and segments 1–3, ventral view. C, segments 4–7, dorsal view. D, segments 5–8, ventral view. E, segments 10–11, ventral view. F, ventral overview. G, Segments 1–3, ventral view. H, segments 4–7, dorsal view. I, segments 5–7, ventral view. J, segments 10–11, ventral view. Abbreviations: gco1, glandular cell outlet type 1; lat, lateral accessory tube; ltas, lateral terminal accessory spine; lts, lateral terminal spine; lvs, lateroventral spine; lvt, lateroventral tube; mds, middorsal spine; te, tergal extensions; vlt, ventrolateral tube.