“Ophiozonella falklandica, n.sp.
St. WS 212. 30. V. 28. 49° 22' S, 60° 10' W, 242 m. ca. 10 adult specimens, and a great number
of young ones.
St. WS 244. 18. vii. 28. 52° 00' S, 62° 40' W, 253 m. Several specimens.
St, WS 818. 17. i. 32. 52° 31' S, 63° 25' W, 272-278 m. 4 specimens.
St. WS 819. 17. i. 32. 52° 45' S, 62° 27' W, 329-242 m. 4 specimens.
St. WS 820. 18. i. 32. 52° 53' S, 61° 51' W, 351-367 m. 6 specimens.
St. WS 821. 18. i. 32. 52° 56' S, 60° 55' W, 461-468 m. 1 specimen.
St. WS 839. 5. ii. 32. 53° 30' S, 63° 29' W, 403-414 m. 1 specimen.
St. WS 871. 1. iv. 32. 53° 16' S, 64° 12' W, 336-341 m. 1 specimen.
Diameter of disk of largest specimen 10 mm.; arms rather robust, scarcely exceeding
three times the diameter of disk.
Dorsal side of disk covered with coarse, but smooth scales, among which the primary
plates are usually very conspicuous ; in the younger specimens there are only some few small plates in the corners between the primary plates, in larger specimens the primary
plates are wholly separated by smaller plates. Generally there are two larger plates in the
interradii. The radial shields are small, oval, widely separated by a series of two to three
plates. The ventral interradii are covered by a varying number of plates, none of which
are particularly conspicuous. The genital slits are narrow and short, not reaching beyond
the end of the first lateral plate. The buccal shields are slightly irregular, with an acute
inner angle; the inner sides concave, the outer edge convex; they may be distinctly longer than broad, or equally long and broad, there being thus a rather considerable
variation in their shape. The adoral shields are short, broad distally, narrowing towards the median line, where they join; sometimes, however, they are about equally broad
in their whole length, almost square. There are three or four square mouth papillae; the
teeth are broad, rounded.
First ventral plate broader than long, with rather sharp corners. The following ventral
plates contiguous till some distance beyond the disk; their outer edge somewhat produced.
Dorsal arm plates contiguous on the proximal three or four joints, with straight
sides and strongly convex distal edge. Two short, conical arm spines, the lowermost the
longer, not half the length of the arm joint. One large, oval tentacle scale. Colour of
the preserved specimens whitish.
This species is viviparous, but not hermaphrodite. There is only one gonad at each
bursa, placed interradially. Some of the larger specimens, 6-8 mm. diameter of disk, were found to have the gonads purely female; one specimen of 5 mm. has the gonads of
purely male character, in another specimen of the same size the gonads contain only
young eggs. There is thus no sign that the species is a protandric hermaphrodite.
I have found two to three young ones in a bursa. They are rather robust, with only
three short, thick arm joints, when ready to leave the mother. The ventral interradii are
occupied almost wholly by the adoral shields, the buccal shield still lying on the dorsal
side, which is otherwise covered only by the large primary plates. It is an interesting
fact that the second mouth tentacle is here still lying wholly outside the mouth slits; the
mouth papillae have not yet been formed (Fig. 31).
Ophiozonella alba (Lütken and Mortensen) ('Albatross' Ophiuroids, pl. vi, figs. 7-9)
would seem to be the nearest relation of the present species, differing from it mainly in
its longer arm spines, and in the arm joints being more constricted. Also the first
ventral plate is characteristically different — much narrower than in O. falklandica.”
(Mortensen, 1936; 301-303)
