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“Aforia magnifica (Strebel, 1908) (Figs 411, 412, 436)
Surcula magnifica Strebel, 1908: 19, pl. 2, figs 23a-d.
Aforia magnifica Powell, 1951: 167, fig. M, 91, p. 195 (radula); Carcelles, 1953: 198, pl. 4, fig. 75; Powell, 1958: 201; Powell, 1960: 158; Powell, 1966: 44.
MATERIAL EXAMINED: Eltanin Stns 138, 410, 428, 432, 435 439, 1003, 1079, 1084. 2079, 2116, 2117, 2119, 2121.
DISTRIBUTION: Records are now known for A. magnifica from the Antarctic Peninsula, South Shetlands, South Orkneys and the South Sandwich Islands (92-1455 m), from the antarctic continent between 62°E and 74°E (177-437 m) and from the Ross Sea (567-1890 m).
REMARKS: Specimens here taken as typical of A. magnifica have a spire angle between 43-46°, a single strong, gently rounded carina on the spire whorls and a second carina of subequal strength developed on the last whorl. Each carina is ornamented with up to four fine spiral threads. The subsutural ramp is largely smooth, with a few fine spiral threads developing closer to the carina. Sculpture between the carina and suture on the spire whorls, and between the two carinae and across the base on the last whorl consists of numerous, fine subequally developed spiral threads.
Two specimens from two separate stations (Eltanin Stns 435 and 1003), from the same general area as specimens conforming to the above diagnosis, differ in having a considerably wider spire angle (50°) with stronger spiral sculpture. The specimen from Stn 1003 is much larger (88.5 mm in length with the canal broken off), the carinae on the later whorls and the last whorl rounded and much less prominent and with the spiral threads on the carinae equal in strength with the rest of the spiral sculpture. There are no intermediates between this latter form and what is taken to be A. magnifica. There does not appear to be much difference in depth range for these two forms, 92-238 m for the variants as against 128-500 m for "typical" magnifica in the Scotia Arc. It cannot therefore be considered that these two specimens represent depth variants. More material may show that these specimens represent a further species of Aforia.
A range of specimens from a series of stations in the Ross Sea have spire angles ranging from 43-47° and agree very well with specimens from the South Shetlands. They appear much less variable in most characters than specimens from the Scotia Arc especially as regards the development of the carinae.
As mentioned and figured by Powell (1966: 44, text figure B22) the radula consists of a broad-based unicuspid central tooth with a wish-bone type marginal, the two limbs of the marginals contiguous.”
(Dell, 1990: 231)