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
Neodrillia crassa
,
new species
(
Plate 135
)
Drillia pagodula
auct. non Dall, 1889: 90: is a misidentification by Dall of specimens from R/V
Blake
Sta. 177, off
Dominica
, and R/V
Blake
Stas. 282, 223 (in part), and 280, off
Barbados
.
Drillia albicoma
auct. non Dall, 1889: 83–84: is a misidentification, in part, by Dall of fragments from off
Barbados
, R/V
Hassler
Exped. off
Barbados
, and R/V
Blake
Sta. 45, off
Barbados
.
Cymatosyrinx pagodula
(Dall, 1889)
: is a misidentification by Sander & Lalli (1982: 317 [
Barbados
]).
Type
material.
Holotype
20.6 x
6.8 mm
(USNM 87472), also a
syntype
of
Drillia pagodula
, Dall, 1889
; lip missing to varix; 7
paratypes
: 2
paralectotypes
of
Drillia albicoma
Dall, 1889
: 19.3 x
6.5 mm
, (USNM 87462) and 10.6 x
4.2 mm
(MCZ 7059), both from
183 m
, R/V
Hassler
expedition; 1 spec., 17.8 x
5.8 mm
, in
200 m
, off Holetown, St. James Parish,
Barbados
,
13°10'52''N
,
059°38'30''W
, F. Sander!
Nov 1978
(ANSP 353515); 4 spec., 26.8 x 10.0, 21.3 x 8.6, 18.6 x 7.2 & 17.2 x
6.5 mm
, in
244–274 m
, in old bottle off Sea Aquarium, Bapor Kibra, Willemstad,
Curaçao
,
Netherlands Antilles
,
12°04'59.51"N
,
68°53'56.61"W
, C. Baldwin! aboard submersible
Curasub
,
8 Feb 2013
(USNM 1231400).
Type
locality.
Off
Dominica
, 15°32′18″N, 061°30′10″W, in 118 fms [
216 m
] (R/V
Blake
Sta. 177).
Other material examined.
An additional nine specimens were examined: 2 spec., 11.3 x 4.2 & 11.2 x
4.1 mm
, in 118 fms [
216 m
] R/V
Blake
Sta. 117 off
Dominica
, 15°32′18″N, 061°30′10″W (USNM 1291373), 4
paralectotypes
of
Drillia pagodula
Dall, 1889
: 9.8 x 3.7, 8.5 x 3.7, 8.0 x 3.4 & 6.9 x 3.0 mm, in 103 fms [
188 m
], R/V
Blake
Station 273, 1878, off
Barbados
(MCZ 7069); 1
paralectotype
of
D. pagodula
Dall, 1889
: 14.0 x
5.2 mm
, in 154 fms [
282 m
], R/V
Blake
Station 282, 1878, off
Barbados
, (MCZ 7068); 1
paralectotype
of
D. pagodula
Dall, 1889
: 9.6 x
3.8 mm
, in 73 fms [
134 m
], R/V
Blake
Station 290, 1878, off
Barbados
, (MCZ 7070); 1 spec., 15.7 x 5.3, in
200 m
, off Holetown, St. James Parish,
Barbados
,
13°10'52''N
,
059°38'30''W
, F. Sander!
Nov 1978
(ANSP 353514).
PLATE 135.
Neodrillia crassa
,
new species
.
Upper panel.
Figs. 1, 3: holotype, off Dominica (USNM 87472). Fig. 1: ventral, lateral & dorsal views; Fig. 3: apical view, V = varix; Fig. 2: enlarged view of protoconch (not to scale) of specimen in Fig. 7.
Lower panel
. Figs. 4–8, 10–11: paratypes. Figs. 4, 5, 7 & 10: off Sea Aquarium, Curaçao, Netherlands Antilles (USNM 1231400); Fig. 6: off Barbados (USNM 87462); Figs. 8, 9: off Holetown, Barbados (ANSP 353515 and ANSP 353514, respectively); Fig. 11: off Barbados (MCZ 7059); Fig. 12: off Barbados (MCZ 7068); Fig. 13: off Barbados (MCZ 7070); Figs. 14–17: off Barbados (MCZ 7069); Figs 18–19: off Dominica (USNM 1291373).
Range and habitat.
Dominica
(offshore);
Barbados
(offshore);
Netherlands Antilles
(off SW
Curaçao
). Reported from
134–
282 m
.
Description.
Shell
medium (to
26.8 mm
in total length), fusiform, truncated anteriorly with a tall spire and a short, narrow anterior canal; shell surface dull, granular-looking. Whorls nearly straight-sided, up to about 11½ total, the last 55% of total length. Sculpture of low, narrow ribs.
Protoconch
eroded on
holotype
, of 2¼ whorls on juvenile
paratype
. Lost or eroded on all the other
paratypes
.
Axial sculpture
of low, narrow, opisthocline ribs that run from suture-to-suture on the spire whorls and to anterior fasciole on last; slightly recurved on whorl shoulders reflecting past positions of anal sinus. Ribs number 15 on penultimate, and 10 on last whorl to varix; intercostal space greater than rib width.
Varix
large, convex, wider and much higher than adjacent ribs, but not hump-like.
Spiral sculpture
of closely-packed heavy raised threads roughened by growth striae. Threads override ribs.
Sulcus
slightly concave, ribs recurved, just a little lower than on whorl proper.
Outer lip
“peeled” back to varix by predator on
holotype
and the larger
paratypes
Anal sinus
mostly missing on
holotype
; a deep laterally-directed notch on some
paratypes
.
Inner lip
moderately wide, recumbent, margined, pinched erect anteriorly, and formed into a weak callus posteriorly where it joins the outer lip.
Anterior canal
moderately long, open, unnotched; anterior fasciole not swollen. Fasciole sculpture is the same as shell base but spiral threads heavier and wider apart.
Color
white with a broad, light golden-brown band from the sulcus to the suture of the succeeding spire whorls, to the lower part of the shell base of last whorl; varix with a darker yellow-brown patch; aperture porcellaneous white.
Remarks.
Taxonomy.
Neodrillia crassa
has the characteristic shell surface microsculpture of
Neodrillia
: closely-packed raised spiral threads roughened by growth striae, a tall spire, and low, slightly opisthocline ribs.
Variability
. The 17 complete specimens have an average total length of
14.54 mm
(
6.9–26.8 mm
), their W/
L ratio
is 0.379. Most shells have some degree of predator damage, the largest specimens with lips chipped back to the varix such that no complete description of a fully developed outer lip is possible.
Identification.
Among its congeners,
N. crassa
is most like
N. albicoma
(Dall, 1889)
but differs in being stouter and a light golden brown in base color, not white. It is also similar to
Fenimorea pagodula
(Dall, 1889)
but differs in detail of the microsculpture, has a broader shell (W/
L ratio
= 0.381 versus 0.330), and more axials (13–15 versus 9–11 on the penultimate whorl). Both can have a faded yellow to orange mid-whorl spiral band, although it is usually more subdued in
N. crassa
.
Etymology.
The Coarse
Neodrillia
, named for the rough shell surface and appearance of examined specimens. From the Latin adjective
crassus
, feminine
crassa
, meaning coarse.