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 phasma
(Schwengel, 1940)
,
new combination
(
Plate 95
)
Crassispira phasma
Schwengel, 1940: 49
–50; pl. 3, fig. 8: Powell (1966: 76); Abbott (1974: 272; sp. 3037); Turgeon
et al.
(1998: 104).
Clathrodrillia phasma
(Schwengel, 1940)
: Williams (2005; 2006; 2009: species 1545).
Not this species or unconfirmed extralimital reports.
Clathrodrillia phasma
(Schwengel, 1940)
: García (2012a: 65–67) [=
Clathrodrillia garciai
,
n. sp.
and
Fenimorea tessellata
,
n. sp.
, white form]).
Clathrodrillia
cf.
phasma
(Schwengel, 1940)
: García (2012a: 65–67 [
=
Fenimorea alba
,
n. sp.
]).
Type
material.
Holotype
27.5 x 11.0 mm (ANSP 176453); 2
paratypes
in MCZ 207357 (not examined).
Type
locality.
off Palm Beach, Palm Beach Co., E Florida, in 12 fms [
22 m
].
Other material examined.
2 spec., 17.9 x 7.3 & 24.0 x 10.0 mm, in
46 m
, E of Government Cut, Miami, E Florida (UF 155667).
Range and habitat.
E Florida (off Palm Beach Co.; off Miami-Dade Co.). Reported from
22–
46 m
.
Description.
Shell
medium (to
27.5 mm
), solid, fusiform, truncated anteriorly, whorls flat around suture, convex below, number up to 9, last approximately 55% of total shell length. Predominant sculptural element is axial ribs. Aperture oval, tapering to a deep anal sinus posteriorly and a very short canal anteriorly.
Protoconch
worn away on the
holotype
.
Axial sculpture
of strong ribs, slightly opisthocline on spire whorls, gathered in to the anterior fasciole on last; ribs greatly reduced in and sharply demarcating the sulcus. Ribs about as wide as their interspaces, 14 on the penultimate and 10 on the last to the varix.
Varix
hump-like, approximately ⅓-turn from the edge of the outer lip.
Spiral sculpture
of microscopic spiral incised threads and subequal growth striae that create jagged spirals; pits appear between the striae. This pattern is overlain by widely spaced spiral grooves that terminate in short projections at the edge of the outer lip, about 10, some additional ones may be worn away.
Sulcus
flat to concave, about ¼ whorl height. Ribs low, slightly curved to reflect anal sinus outline; spiral threads closer than on whorl below.
Outer lip
thick, flattened from the varix with several strengthening folds; lip edged forms a flat arc from anal sinus to stromboid notch.
Anal sinus
a deep U-shaped notch on whorl shoulder, constricted somewhat by parietal lobe and outer lip; inner edge of sinus flared outward.
Inner lip
recumbent, thick anteriorly along canal, developed into a lobe posteriorly on parietal wall.
Anterior canal
short, open, notched; fasciole not swollen, with the same microsculpture as on shell base.
Color
white.
Remarks.
Taxonomy.
Fenimorea phasma
first appeared combined in
Fenimorea
in the USNM on-line database. The
holotype
has the distinguishing characteristics of
Fenimorea
: the typical shell surface microsculpture, including overlying spiral grooves that end in projections at lip’s edge, ribs that extend from suture-to-suture but change in the sulcus, a hump-like varix, and a short anterior canal. An all-white specimen is usually suspected of being just a white form of a species that is otherwise colored.
F. phasma
is not an all-white form of
F. j a ne t a e
; that species lacks marginal teeth on the outer lip (see
Plate 82
). It more closely matches the white form of
F. tessellata
, which has marginal teeth; however, that species has more angular shoulders and is known principally from the Gulf of
Mexico
. Two other specimens believed to be
F. phasma
, which are in UF 155667, are in better condition. Although possessing shorter spires they are otherwise very similar morphologically. These specimens support the likelihood that
F. phasma
is a genuine species, and perhaps naturally all-white. Future finds will be important to confirm its validity.
Variability.
Too few specimens have been examined to describe its natural range in size and form, sculpture and color. The
holotype
appears to be a gerontic specimen, when compared with the other specimens identified as this species.