Abstract
A new deep-sea species of Volutidae in the genus Tractolira is named from material collected by the United States Antarctic Program in and around the Ross Sea, eastern Antarctica, and from one locality in the Subantarctic region. Tractolira delli new species is most similar to T. sparta Dall, 1896, from which it differs in having a relatively wider shell, less prominent spiral sculpture, with narrower threads, and by the absence of strong axial ribs at least on the first three teleoconch whorls. The other Antarctic congener, Tractolira germonae, has a thicker, dark-brown periostracum (instead of a thin, light-yellow one), a proportionally smaller inductura, and lacks surface sculpture.References
Dall, W.H. (1896) Diagnoses of new species of mollusks from the west coast of America. Proceedings of the United States National Museum, 18 (1034), 7–20.
Dall, W.H. (1907) A review of the American Volutidae. Smithsonian Miscellaneous Collections, 48(3), 341–373.
Dell, R.K. (1990) Antarctic Mollusca with special reference to the Ross Sea. Bulletin of the Royal Society of New Zealand, 27, 1–311.
Harasewych, M.G. (1987) Tractolira germonae, a new abyssal Antarctic volute. The Nautilus, 101, 3–8.
Leal, J.H. & Bouchet, P. (1989) New deep-sea Volutidae from off southeastern Brazil. The Nautilus, 103, 1–12.
Sowerby, G.B. (1846) Descriptions of Tertiary fossil shells from South America. In: Darwin, C. (Ed.) Geological observations on South America, being the third part of the geology of the voyage of the Beagle, under the command of Capt. Fitzroy, R. N. during the years 1832 to 1836. Smith, Elder and Co., London. Appendix. pp. 249–264, pls. 2–5.