Synoptic Keys to the Genera of Ophiuroidea
Family Hemieuryalidae Verrill, 1899
Family Hemieuryalidae Verrill, 1899
1 (8) |
Dorsal arm-plates partly or completely subdivided into smaller plates: 3 short, flat arm-spines and 1 short, flat tentacle-scale (Subfamily Hemieuryalinae Matsumoto, 1915). |
2 (3) |
Dorsal arm-plates completely fragmented, forming a mosaic. . . . Hemieuryale von Martens, 1867. *pustulata v. Mart., 1867. West Indies. 100 fms. |
3 (2) |
Dorsal arm-plates subdivided into a larger medium portion, plus some other plates or platelets. |
4 (7) |
A large supplementary plate on either side of each dorsal plate. |
5 (6) |
One genital cleft in each interradius. . . . Quironia A. H. Clark, 1934. *johnsoni A. H. C., 1934. West Indies. Littoral. |
6 (5) |
Two genital clefts in each interredius. . . . Sigsbeia Lyman, 1878. *murrhina Lyman, 1878. Cuba. 175 fms. |
7 (4) |
Dorsal arm-plates of adjacent segments separated by an intervening transverse row of small platelets. . . . Ophioplus Verrill, 1899. *Hemieuryale tuberculosa Lyman, 1883. West Indies. 100 fms. |
8 (1) |
Dorsal arm-plates entire; without supplementary plates: 5–8 conical armspines: no tentacle-scale, but lowest arm-spine may serve as one (Subfamily Ophiochondrinae Verrill, 1899, emend. Matsu. 1915). |
9 (10) |
Disc-plates covered by a thick granulated skin. . . . Ophiochondrus Lyman, 1869. (Mortensen, 1927, 1936, has referred this genus to the Ophiacanthidae, without discussion.) *convolutus Lyman, 1869. Cuba. 270 fms. |
10 (9) |
Disc-plates naked. |
11 (18) |
Ventral arm-plates developed normally throughout arm. |
12 (13) |
Paired interradial sacs between the oral shields and radial shields. . . . Ophioleila A. H. Clark, 1949. *elegans A. H. C., 1949. Hawaii. 600 fms. |
13 (12) |
Interradii of normal form, without interradial sacs. |
14 (17) |
Disc circular in outline: uppermost arm-spines longer than others. |
15 (16) |
Genital clefts pore-like, placed beside the small oral shield. Ventral interradius covered by several polygonal plates. Primary plates inconspicuous. . . . Amphigyptis Nielsen, 1933. *perplexa Niel., 1933. Panama. Littoral. |
16 (15) |
Genital clefts elongate. Single large plate covers the ventral interradius. Primary plates conspicuous. . . . Ophiocyclus H. L. Clark, 1939. *Ophioceramis clausa Lyman, 1878. Kermadec Is. 600 fms. (It seems doubtful whether this genus is distinct from Amphigyptis, of which it may be a developmental stage.) page 13 |
17 (14) |
Disc distinctly 5-lobed owing to the larger radial shields and contracted interradii. . . . Ophiomoeris Koehler, 1904. Syn: Ophiurases H. L. Clark, 1911. *spinosa Koehler, 1904. Kei Is. 160 fms. |
18 (11) |
Ventral arm-plates beyond the three basal arm-segments either lacking or fragmented. |
19 (20) |
Ventral arm-plates lacking beyond the third basal segment, and replaced by a ventral furrow. . . . Ophioholcus H. L. Clark, 1915. *Sigsbeia sexradiata Koehler, 1914. West Indies. 350 fms. |
20 (19) |
Ventral arm-plates beyond the third basal segment are fragmented into small platelets. . . . Ophiogyptis Koehler, 1905. *nodosa K., 1905. Indonesia. 50 fms. |