Late Pliocene; Extinct.
Original Description (from Mansfield, 1930, p. 42-43):
"Shell small, somewhat turrited, with subangulated whorls constricted at the suture, and consisting of 1.5 nuclear and 5.5 postnuclear whorls. Nuclear whorls small and smooth. Following whorl inflated and ornamented with fine, granulose spiral threads, giving it under magnification a faint reticulate appearance. Following whorls subangulated - the periphery being a little nearer the upper suture. Axially sculptured with vertical riblets on the earlier whorls and ribs on the later spire whorls and body whorls. Ribs cross the spire whorls and on the body whorl extend to the canal. Spiral sculpture on spire whorls of 4 primary threads and from 2 or 3 microscopic threadlets between the primaries and several in front of the suture. The first primary is weaker and lies in front of the periphery, the second occupies the periphery, the third lies on the anterior slope, and the fourth lies behind the suture. The finely granulose spirals and minute connecting bars give the shell under magnification a frosty appearance. Canal short. Margin of outer lip broken. Inner surface of columella provided with a thin wash of callus.
Type (U.S.N.M. Cat. No. 369979) measures: Altitude, 5.5 mm.; diameter, 2.1 mm.
The species is described from two specimens, the larger specimen, with missing nucleus, constituting the type and the smaller specimen, with a well preserved nucleus, the paratype.
The nearest related Recent species appears to be Mangilia atrostyla Dall.
The new species is named in honor of Dr. Julia A. Gardner, of the U.S. Geological Survey.
Occurrence: Upper Miocene: Station 1/670, upper bed at Alum Bluff, Liberty County, Fla., type locality; station 1/955, Gully Pond, Washington County, paratype locality; 1/964, Harveys Creek, at abandoned mill, highest bed; station 3423, Jackson Bluff, Leon County, lower upper Miocene bed. Rare at all localities."
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