Genus Euryale Lamarck, 1816

Fig. 9

Type species

Euryale aspera Lamarck, 1816 .

Examined species

Euryale aspera .

Oral GP

Absent.

Adradial GP

Bar-like, distally thickened, curving upwards, flat articular structure and shallow groove.

Abradial GP

Isosceles triangular, thick, distal end straight, proximal end pointed, attaches along proximal dorsal edge of adGP.

Oral shields

All madreporic.At size 22 mm dd, minute, externally one or two pores visible. Internally, one madreporite elongated (slipper-shaped), proximally rounded and closed over, in middle a square opening, distal part narrower, tube-like closed, distal end open. Another madreporite internally not closed over, with deep openings and several septa. Only distal surface externally visible at vertical interradius, madreporite placed on inner side of two adradial shields, completely covered.

Radial shield

Bar-like, curved, distal end in dorsal aspect spatulate, widened, in ventral aspect rounded, gradually increasing in thickness from proximal to distal, articular structures as two flat patches, one on ventral side, one as distal surface. Proximal to articular structures a concave part with several holes.