Synoptic Keys to the Genera of Ophiuroidea
Family Ophiactidae Matsumoto, 1915
Family Ophiactidae Matsumoto, 1915
1 (8) |
Disc scaled above and below. |
2 (3) |
A circle of small platelets surrounds each dorsal arm-plate: granules or spinules on disc, but primary plates naked and distinct: lower arm-spine hooked on distal part of arm. . . . Ophiopholis Mueller & Troschel, 1840. *Ophiolepis scolopendrica M. & T. = Asterias aculeatus Retzius, 1783. N. Hemisphere. Littoral and deep water. |
3 (2) |
Dorsal arm-plates contiguous, not surrounded by platelets. |
4 (7) |
No spines on disc: not fissiparous: five arms. |
5 (6) |
Radial shields united in pairs: three oral papillae, of which the outermost is enlarged (but not operculiform), all three papillae partly fused together: genital clefts present: the male dwarfed and carried on the ventral surface of the female. . . . Ophiodaphne Koehler, 1931. *materna Koehler, 1931. Indonesia. 100 fms. |
6 (5) |
Radial shields separated: not androphorous. No genital clefts: two or three oral papillae: one tentacle-scale. . . . Ophiopus Ljungman, 1866. Syn.: Ophiaregma Sars, 1872. *arcticus Ljungman, 1866. Arctic. 600 fms. |
7 (4) |
Spines present on disc, though not so numerous as to conceal the coarse scales: often with six or seven arms, and reproducing by transverse fission of the disc: one or two oral papillae. . . . Ophiactis Lütken, 1856. Syn.: Amphiactis Matsumoto, 1915 (non Verrill, 1869). *krebsii Lütk. = Ophiolepis savignyi M. & T., 1842. Tropics. |
8 (1) |
Disc scaled above but naked below: a single (outer) oral papilla: adoral shields all in contact, thus forming a continuous ring around the mouth: radial shields united in pairs. . . . Hemipholis Lyman, 1865. *Ophiura elongata Say, 1825. Caribbean. Littoral. |