Borsonella diegensis

Borsonella diegensis
Original drawing of a shell of Borsonella diegensis
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Neogastropoda
Superfamily:	Conoidea
Family:	Borsoniidae
Genus:	Borsonella
Species:	B. diegensis
Binomial name
Borsonella diegensis (Dall, 1908)
Synonyms [1]
Borsonia diegensisDall, 1908 Borsonia (Borsonella) diegensisDall, 1908 Spirotropis (Borsonella) diegensis(Dall, 1908)

Borsonella diegensis is a species of sea snail, a marine gastropod mollusk in the family Borsoniidae. ^[1]

Description

Length of four whorls, 15.0 mm; of body whorl, 12.5 mm ; of aperture, 9.5 mm ; max. diam. 8.0 mm.

(Original description) The small shell is stout, solid, decollate, with a whitish substratum and strong olivaceous periostracum. The four remaining whorls are closely coiled and have the aperture longer than the remaining portion of the spire. The sculpture consists of a strong spiral keel, peripheral on the spire with more or less nodulation (in cue specimen with fifteen small nodules on the penultimate whorl, but none on the body whorl; another has them obsolete on the spire), stronger on the earlier whorls when present, an obscure ridge in front of the suture, stronger on the earlier whorls. There is a faint spiral striation on the anal fasciole between the ridge and the keel. The whole surface is covered with a microscopic, close, impressed, vermicular network of fine lines anastomosing in every direction. On the body whorl the keel is well above the periphery. The base of the shell is evenly rounded. The aperture is ample. The anal sulcus at the suture is wide and deep. The thin outer lip is arcuately produced. The columellar lip is smooth, with a glaze of callus. The plication on the proximal part of the columella lags behind the aperture. The siphonal canal is very wide and short and has an obsolete fasciole. ^[2]

Distribution

This species occurs in the Pacific Ocean off California.

References

1. Borsonella diegensis (Dall, 1908) . Retrieved through: World Register of Marine Species  on 13 August 2011.
2. W.H. Dall (1908): Reports on the Dredging Operations off the West Coast of Central America to the Galapagos, to the West Coast of Mexico, and in the Gulf of California, in charge of Alexander Agassiz, carried on by the U. S. Fish Commission Steamer "Albatross," during 1891, Lieut. Commander Z. L. Tanner, U. S. N., Commanding. XXX VII. Reports on the Scientific Results of the Expedition to the Eastern Tropical Pacific, in charge of Alexander Agassiz, by the U. S. Fish Commission Steamer "Albatross," from October, 1904, to March, 1905, Lieut. Commander L. M. Garrett, U. S. N., Commanding. XIV. The Mollusca and the Brachiopoda; Bulletin of the Museum of Comparative Zoology at Harvard v. 43 p. 275 (1904)