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
Splendrillia vinki
(Jong & Coomans, 1988)
,
new combination
(
Plate 161
)
Inodrillia vinki
Jong & Coomans, 1988: 112
–113, pl. 43, fig. 597: Williams (2005; 2006; 2009: species 3255, three left-most photos only).
Not this species or unconfirmed extralimital reports.
|
Inodrillia vinki
auct non Jong & Coomans, 1988: Williams
|
(2009: |
species |
3255, |
right-most |
photo |
=
Bellaspira
|
rosea
,
|
new |
species). |
Type
material.
Holotype
12 x
4.0 mm (ZMA 3.87.099) according to Jong & Coomans (1988: 112–113). The
holotype
is missing (M. Faber, research notes); a photograph of the
holotype
, taken by these authors and provided by Faber, was used as a representation of the
type
(Pl. 161,
Fig. 1
).
Type
locality.
Malmok,
Aruba
,
Netherlands Antilles
.
Material examined.
An additional
18 specimens
were examined: 2 spec., 8.9 x 3.5 & 8.5 x
3.1 mm
, on coralline sand at
1.8 m
,
Aruba
(USNM 1291365); 1 spec., 9.6 x
3.5 mm
, on coralline sand at
1.8 m
,
Aruba
(ANSP 464959); 1 spec., 8.7 x
3.5 mm
,
Aruba
, T. McCleery!,
Dec 1998
(ANSP 464960); 2 spec., 12.1 x 4.3 & 10.7 x
3.9 mm
, Malmok, M. Beerman!,
24 Aug 1967
(UF 496647); 9 spec., 12.3 x
4.3 mm
(UF 470345), 13.1 x 4.5, 14.6 x 4.8, 12.2 x 4.8, 9.9 x 3.6, 11.1 x 4.2, 10.2 x 4.4, 11.4 x 4.4 & 10.5 x
3.7 mm
(author’s coll.), all beach collected, Malmok and Punta Braboe, A.N. de
Mann
!
Mar–Jun 1964
and
Aug 1966
; 2 spec., 8.2 x 3.0 & 8.9 x
3.2 mm
, in
10– 15 m
, Malmok,
Aruba
, T. McCleery,
Jan 2008
(BMSM 14998); 1 spec., 10.3 x
3.7 mm
, in
100–120 m
, off Cape Arraial, Rio de Janeiro,
Brazil
, P. Gonçalves! Apr, 2011 (MZSP
122076
).
Range and habitat.
Aruba
;
Brazil
(off Cape Arraial, Rio de Janeiro). Reported from
2–15 m
from
Aruba
;
100–120 m
from off Rio de Janeiro,
Brazil
.
Description.
The original is based on a single specimen with an immature lip so mature specimens, non-types, were examined to more fully characterize the species.
Shell
small (to
14.6 mm
), narrowly fusiform with a truncated anterior, glossy, with up to 9 slightly convex whorls, the last whorl 58% of the total shell length.
Protoconch
of 2 smooth whorls.
Axial sculpture
of slightly oblique ribs confined mostly to the periphery of the whorls, almost knob-like, terminating at the sulcus, the first teleoconch whorl has weak riblets at first and altogether more ribs than the second, 9–12 are on the penultimate whorl and 5–8 on the last whorl to the varix. Space between the axials greater than their width. Growth striae present; most pronounced on the body whorl from the varix to the edge of the outer lip.
Varix
weak, hump-like about ¼-turn from edge of outer lip.
Spiral sculpture
mostly absent; approximately 2 faint spiral ridges visible on the lower portion of the shell base, and 4 ridges on the anterior fasciole.
Sulcus
flat, without spiral or axial sculpture.
Outer lip
thin, outer edge runs in a low arc from the anal sinus to the anterior canal without any inflection and projecting out from the circumference of the shell; flattened behind from the varix to its edge; lip edge slightly inflected. Stromboid notch present but very shallow, close to the tip of the canal.
Anal sinus
moderately deep, adjoins suture at its apex behind parietal callus.
Inner lip
margined anteriorly, thin or absent on the parietal wall, ending in a callus at the suture.
Anterior canal
short; open, barely demarcated from the anterior portion of the aperture; sulcus not swollen; tip of canal slightly notched.
Color
light to dark caramel; leading edge of varix and broad indistinctly margined central band between ribs darker, shell apex, anterior fasciole, aperture and outer lip lighter to white, as are rib crests. All very light-colored specimens are beach-collected and probably faded.
Remarks.
Taxonomy.
Splendrillia vinki
has all the characteristics of
Splendrillia
. The genus
Inodrillia
Bartsch, 1934
(
Crassispirinae
, Tippett, 1995: 135), its original placement, is characterized by the presence of riblets on the second protoconch whorl. The growth striae that appear at the end of the smooth whorls of the protoconch of
S. vinki
or the numerous ribs of the first teleoconch whorl may have been interpreted as being protoconch riblets, but
Inodrillia
also has strong axial ribs and spiral threads on the teleoconch, and a strong varix a little behind the outer lip.
As
with crassispirines in general,
Inodrillia
has a thick parietal callus that extends up to the suture forming a shelf that partially occludes the opening of the anal sinus in mature specimens. These features are not found in
S. vinki
.
Variability
. The average total length of
17 specimens
is
10.95 mm
(
8.5–14.6 mm
) and their average W/
L ratio
is 0.368. Color varies from very light to dark caramel, with a white apex, anterior, and rib crests. The specimen from off Cape Arraial, Rio de Janeiro represents a significant geographic jump from all other known occurrences (Pl. 161, Fig. 10). It also varies from the
type
in possessing somewhat stronger ribs, a larger protoconch, and darker caramel color. These differences are not believed to rise to the level of species, however.
Identification
.
Splendrillia vinki
resembles
S. interpunctata
(E.A. Smith, 1882)
, but is smaller and differs in color. It differs from
S. coccinata
(Reeve, 1845)
principally in the number and form of the axials, which are more angular, longer and more numerous in
S. coccinata
, and also in shell color.
Splendrillia vinki
also resembles
Lissodrillia cabofrioensis
,
new species
, which was compared under that species, and
Cerodrillia brasiliensis
,
new species
, but that species has axial ribs extending to the suture, and an entirely different anal sinus and varix structure.