Cucumaria, de Blainville, 1830

Thandar, Ahmed S., 2019, On some lesser known sea cucumbers in the Natural History Museum, UK (Echinodermata: Holothuroidea), Zootaxa 4688 (3), pp. 361-381 : 377

? Cucumaria sp. indet.

Figure 10

Material examined. 1850.7.3.24, Falmouth, 1 spec.

Description. Specimen cylindrical, 62 mm in length, 21 mm in breadth, apparently a mud or sand-dwelling form due to adhering sand grains, hence skin rough to touch. Tentacles 9, well branched, ventral two reduced. Calcareous ring far anterior, almost cartilaginous or much reduced. Tube feet restricted to radii in 2–4 rows per radii, well developed, short, but retractile, suckers well developed. Retractors and respiratory trees well developed, the former extend very far forward due to anterior displacement of calcareous ring. No ossicles detected in tentacles, introvert, tube feet and body wall.

Remarks. Because of the poorly developed calcareous ring and the lack of ossicles in any part of its body the definitive identification of this specimen is not possible. It may represent Cucumaria frondosa ( Gunnerus, 1767) but this species, although known to lose its ossicles with age has 10 equal tentacles and according to Mortensen (1927) is restricted to northern Europe. The current specimen is juvenile and hence should have retained at least some ossicles or all are perhaps dissolved in the preservative. For its size the calcareous ring is very much reduced to be almost cartilaginous.

Figures

FIGURE 10.?Cucumaria sp. indet. 1850.7.3.24; Falmouth. A. Dorso-lateral view; B. Ventro-lateral view.