Fenimorea contracta Fallon, 2016, new species
Creators: name: Fallon, Phillip J.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Neogastropoda
Drilliidae
Fenimorea
Fenimorea contracta

description: Fenimorea contracta, new species
(Plate 72)
Type material. Holotype 15.3 x 5.4 mm, R. Black! aboard R/V Ike, 20 Apr 1967 (UF 170316). Type locality. NE of Contoy Light, Quintana Roo, Mexico, in 100 fms [183 m]. Range and habitat. Known only from the holotype.
Description. Shell small (to 15.3 mm total length), narrowly fusiform, surface glossy smooth; whorls convex, number 8½, last whorl 57% of total shell length; ribs the predominant sculpture; aperture narrow. Protoconch of 2 smooth round whorls. Axial sculpture of bold straight ribs that run from suture-to-suture on spire, evanesce on base, aligned on all but last 2 whorls; ribs number 5 on penultimate, 4 on last whorl to varix, intercostal space wider than ribs. Varix narrow, approximately ⅓-turn from edge of outer lip. Spiral sculpture of very fine threads or grooves, intersected and made jagged by microscopic growth striae; threads spaced more closely in sulcus. Sulcus not distinct, demarcated where ribs are slightly narrowed, recurved, and slightly reduced in height. Outer lip thin, somewhat flattened from varix to lip’s edge; with 5 irregular post-varical folds; edge of lip from anal sinus to anterior canal relatively straight, not curved, smooth not toothed; stromboid notch absent. Anal sinus a deep Ushaped notch next to the suture; with a lobe on the parietal side, and a callus thickening around the apex of the sinus. Inner lip anteriorly pinched up along canal, widest on columella, narrow on parietal wall, and thickened into a lobe near the suture posteriorly. Anterior canal of moderate length for the genus, open, notched at its end; fasciole not swollen. Color light saffron overall with golden brown patches confined to intercostal spaces.
Remarks. Taxonomy. Fenimorea contracta has the characteristic shell surface microsculpture of Fenimorea, ribs suture-to-suture, and a deep U-shaped anal sinus. Its narrow varix, narrow sulcus, and anterior canal, which is of moderate length are typical of offshore species (as exemplified by F. j a ne t a e Bartsch, 1934). Near shore species, such as F. fucata (Reeve, 1845), generally have broad varices, wide sulci, and short anterior canals. Identification. Fenimorea contracta is most similar to F. crocea, new species in color, size, but differs in having fewer ribs and narrower profile (W/L of holotypes = 0.353 versus 0.386). The narrow profile and presence of only five ribs on the single specimen is unique enough to distinguish this taxon from its congeners and merit its description as a new species.
Etymology. The Narrow Fenimorea. Named for its narrow form. From the Latin adjective contractus, feminine contracta, meaning narrow/restricted/pinched.
description: Published as part of Fallon, Phillip J., 2016, Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species, pp. 1-363 in Zootaxa 4090 (1) on pages 156-157, DOI: 10.11646/zootaxa.4090.1.1, http://zenodo.org/record/263299