Taxonomic review of tropical western Atlantic shallow water Drilliidae (Mollusca: Gastropoda: Conoidea) including descriptions of 100 new species
Author
Fallon, Phillip J.
text
Zootaxa
2016
4090
1
1
363
journal article
10.11646/zootaxa.4090.1.1
e6b35f5a-435e-4473-b29e-1e4d842f84b0
1175-5326
263299
203BAC25-B542-48FE-B5AD-EBA8C0285833
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
.
PLATE 72.
Fenimorea contracta
,
new species
. Figs. 1–3: holotype, NE of Contoy Light, Quintana Roo, Mexico (UF 170316). Fig. 1: ventral, lateral & dorsal views; Fig. 2: enlarged view of protoconch (not to scale); Fig. 3: apical view, V = varix, L = edge of outer lip.
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.