Evoplosoma

Mah, Christopher L., 2020, New species, occurrence records and observations of predation by deep-sea Asteroidea (Echinodermata) from the North Atlantic by NOAA ship Okeanos Explorer, Zootaxa 4766 (2), pp. 201-260 : 226

Evoplosoma sp. 2

Figure 10F

This species was observed once. It was identified on the basis of the full series of pointed spines present on the superomarginal and inferomarginal plates as well as the short spinelets present on the abactinal surface and with distinct marginal plates forming an angular border around the animal’s periphery. The disk was yellow to white on the disk with darker orange on the superomarginals and on the arms.

Based on comparisons with known taxa, this species is diagnosed as a likely undescribed species. When compared with other species of Evoplosoma as summarized in Mah (2015) this species invites comparison with Evoplosoma watlingi Mah 2015 and with Evoplosoma nizinskiae n. sp. as described herein. The image of this species shares the abactinal spination and the full marginal spine series of E. watlingi , but comparison with in situ imagery of these two species suggests very different body color. Evoplosoma watlingi , from Bear Seamount (North Atlantic) is a deep-orange in color and has much thicker and more abundant spines.

This species has a full series of superomarginal spines whereas those spines in Evoplosoma nizinskiae n. sp. are absent interradially. Abactinal spines are also absent in E. nizinskiae . Color and body shape of this species are very similar to E. nizinskiae and further specimens might show further variation or other data which were not available from imagery.

Occurrence: Mona Canyon East, Puerto Rico, 2393 m.

Images Examined

Mona Canyon East, Puerto Rico, 18.544045, -67.294813, 2393 m EX1811_IMG_20181112T 160803 Z_ROVHD.jpg

Figures

FIGURE 10. Evoplosoma nizinskiae & Evoplosoma spp. Small specimen, USNM 1550630 unless otherwise noted. A. Abactinal plates. Scale=1.0 mm. B. Furrow spination differences. Scale=1.0 mm. C. In situ feeding observation. R=1.8 cm. D. E. nizinskiae feeding observation West Florida Escarpment, Gulf of Mexico. 2181 m. E. Evoplosoma sp. 1, Blake Ridge, North Atlantic, 3388 m. F. Evoplosoma sp. 2, Mona Canyon East, Puerto Rico, 2393 m.