Taxonomic study on the molluscs collected in Marion-Dufresne expedition (MD 55) to SE Brazil: Xenophoridae, Cypraeoidea, mitriforms and Terebridae (Caenogastropoda)
Author
Simone, Luiz Ricardo L.
Author
Cunha, Carlo M.
Museu de Zoologia da Universidade de São Paulo, caixa postal 42494, 04218 - 970 São Paulo, SP (Brazil) lrsimone @ usp. br lrlsimone @ gmail. com
lrsimone@usp.br
text
Zoosystema
2012
2012-12-31
34
4
745
781
http://dx.doi.org/10.5252/z2012n4a6
journal article
10.5252/z2012n4a6
1638-9387
5166650
857CAD31-66E1-4CEE-AB4D-CCD64541D0EF
Terebra leptapsis
Simone, 1999
(
Fig. 11
I-K)
Terebra leptapsis
Simone, 1999: 229-233
, figs 7F, 12B, C, 13F, 14C, G, 21, 22; 2000: 138, 144-149. —
Faber 2007: 50
(in synonymy), figs 10, 11. —
Lima
et al
. 2007: 65
. —
Rosenberg 2009
(in synonymy). —
Terryn 2011: 66
.
Terebra leptaxis
–
Faber 2007: 50
(error).
TYPE MATERIAL
(
EXAMINED
). —
Holotype
:
Brazil
,
Rio de Janeiro
,
Campos Bay
,
c.
21°7’S
,
40°53’W
,
MZSP 28704
(
Fig. 11
I-K) (
R
/
V
Austrogagoupa
).
Paratypes
: same data as
holotype
,
MZSP
28705,
1 specimen
,
MZSP
28706, 13 shells.
MATERIAL EXAMINED
. — The same as
Simone (1999: 229)
.
TYPE LOCALITY
. —
Brazil
,
Rio de Janeiro
, Campos Bay,
c.
21°7’S
,
40°53’W
(
R
/
V
Austrogagoupa
).
DISTRIBUTION. —
Rio de Janeiro
to
São Paulo
.
DESCRIPTION
See
Simone (1999: 229-233)
.
MEASUREMENTS (in mm). —
Holotype
: 16.0 × 4.5.
HABITAT. — Sandy bottoms,
32-64 m
depth.
Terebra doellojuradoi
Carcelles, 1953
(
Fig. 11
E-H)
Terebra doello-juradoi
Carcelles, 1953: 14
, 15, pl. 3, fig. 21.
Terebra doellojuradoi
–
Scarabino 2004: 323
, 234. —
Faber 2007: 50
(in part). —
Lima
et al
. 2007: 63
. —
Rosenberg 2009
. —
Terryn 2011: 66
.
N.B.: all remaining citations for samples north from
Uruguay
almost certainly represent misidentifications and belong to other species of the complex, and, therefore, were excluded from this synonymic list.
TYPE MATERIAL
(
EXAMINED
). —
Holotype
:
Uruguay
,
35°53’S
,
53°54’W
,
61.88 m
depth
,
MACN 23439
(
Fig. 11
E-G)
.
Paratypes
:
Uruguay
,
Mar del Plata
,
Banco de Mejillones
,
MACN 10319
,
1
shell
;
35°53’S
,
53°54’W
,
61 m
,
MACN 24278
,
1
shell
;
36°25’S
,
54°38’W
,
54 m
,
MACN 23439
,
1
shell (
Fig. 11H
)
.
TYPE LOCALITY
. —
Uruguay
,
35°53’S
,
53°54’W
,
61.88 m
depth.
DISTRIBUTION. —
Uruguay
to north
Argentina
.
DESCRIPTION
See
Carcelles (1953: 14)
. Complement:
Shell: up to
20 mm
, width
c.
¼ of length, spire angle
c.
20°. Colour uniform beige to pale brown (
Fig. 11E, G
). Protoconch pointed, smooth, of three whorls (
Fig. 11F
); width
c.
14% of maximum teleoconch width; length
c.
5% of shell length. Limit between protoconch and teleoconch distinct, orthocline (
Fig. 11F
). Teleoconch up to 10 whorls; profile weakly convex, suture clear but shallow. Sculpture of all teleoconch whorls with about same arrangement of threads. Except for increment of axial and spiral threads;
c.
24 axial threads and
c.
10 threads in penultimate whorl, axial threads slightly broader and spiral threads; spiral threads not uniform in size and distance from each other, but lying in a somewhat equidistant arrangement from each other, space between neighbouring axial threads about twice each thread width; interval between axial threads equivalent to their width. Sculpture of peri-umbilical area composed of 8-9 spiral liration along entire surface (
Fig. 11E
). Aperture somewhat prosocline, elliptic, about 1.5 longer than wide. Outer lip thick, simple. Inner lip with weak callus; parietal region in upper third, marked by abrupt curve in
c.
90°; siphonal region marked by bright curve to left (
Fig. 11E
). Canal short, narrow, slightly curved to left.
MEASUREMENTS (in mm). —
Holotype
: 10.2 × 2.4;
paratype
MACN 24278: 8.5 × 2.2.
HABITAT. — “Rocky bottoms” (
sic
Carcelles 1953:14
),
54-100 m
depth.
FIG. 11. — Terebrids:
A
,
Terebra alagoensis
Lima,Tenório & Barros, 2007
,holotype MZSP 84238 (L 10.5 mm), frontal view;
B
,
C
, details of apical region in two opposite views;
D
, detail of last whorl, frontal-slightly profile view;
E
,
Terebra doellojuradoi
, holotype MACN 23439, frontal view (L 10.2 mm);
F
, same, detail of protoconch and first whorls;
G
, same, profile view;
H
, paratype MACN 24278, frontal-slightly profile view (L 8.5 mm);
I
,
T. leptapsis
, holotype MZSP 28704, frontal view (L 16.0 mm);
J
, detail of protoconch in SEM;
K
, dorsal view;
L
,
T. crassireticula
, holotype MZSP 27930 (L 22.0 mm).
DISCUSSION ON TEREBRIDS
Several aspects of the characters of the species belonging to the
Terebra doellojuradoi
complex can be found elsewhere (
Simone 1999
,
2000
;
Simone & Gracia 2006
). The present paper was more focused on the four studied species, mainly concerning the MD55 collected specimens, and to the taxonomic problem related to
T. leptapsis
.
Terebra leptapsis
has been considered a synonym of
T. doellojuradoi
, in such the differences pointed out in the original description of the former (
Simone 1999
) have been overlooked (
Faber 2007: 50
;
Rosenberg 2009
). However, a closer look of the type specimens of
T. doellojuradoi
deposited at MACN revealed additional characters which are incompatible with such interpretation.Two of
T. doellojuradoi
types are shown in
Figure 11
E-H (
Fig. 11
E-G:
holotype
;
Fig. 11H
:
paratype
) for a comparison with the
holotype
of
T. leptapsis
(
Fig. 11
I-K).
Terebra doellojuradoi
is smaller, with length around
18 mm
(the
holotype
is
20.5 mm
long), while
T. leptapsis
specimens commonly are over
25 mm
long. The sculpture of both species is quite variable, possessing some overlap of characters, but both
holotypes
are good specimens to show that
T. doellojuradoi
normally bears more spiral threads than
T. leptapsis
(compare penultimate whorl in
Figure 11E and I
). The inverse happens with axial sculpture, in which
T. leptapsis
tends to possess more axial threads (
c.
30 in
penultimate whorls) than
T. doellojuradoi
(
c.
20 in
the same region). Regarding to the sculpture, both species are clearly closely related when compared to other species of the
T. doellojuradoi
complex, e.g.,
T. crassireticula
(
Fig. 11L
) and others. The spire angle is also a quite different,
T. doellojuradoi
has about 20°, while
T. leptapsis
normally has 15-17°. The aperture is also informative, as
T. doellojuradoi
has a somewhat shorter and slightly broader one than
T. leptapsis
(
Fig. 11E, H, I
). However, the protoconch bears the solidest features for distinction of both species; that of
T. doellojuradoi
is multispiral (about three whorls) (
Fig. 11F
) and proportionally narrower and smaller than the protoconch of
T. leptapsis
, which is paucispiral (
c.
1.5 whorl) (
Fig 11J
).
Based on these differences, it looks improbable that
Terebra leptapsis
is a synonym of
T. doellojuradoi
, and represents a distinct species. The former occurs from
Uruguay
to north
Argentina
, the latter occurs in southeastern
Brazil
. Besides, based on this study and on the endemicity of the species of the
T. doellojuradoi
complex, the occurrence of
T. doellojuradoi
in other regions is indeed questionable, such as Gulf of Mexico (
Bratcher & Cernohorsky 1987
). Those reports have not been neither considered here.
The presence of a columellar callus or tooth in the inner lip has been regarded as appearing only in the maturity (
Faber 2007: 50
). This is not accurate, as the columellar fold has been found running along columella in broken specimens (e.g.,
Terryn 2011: 65
, fig. 5), which suggests its presence since immature phases. The columellar tooth is more common in northern species, and has been virtually absent in southern specimens, mainly those occurring in southeastern
Brazil
to north
Argentina
(
Figs 10C
;
11E, I
), including
T. doellojuradoi
. Conversely,
T. alagoensis
possesses a pair of teeth in the inner lip (
Fig. 11D
), which is a distinction of this species amongst the other species of the
T. doellojuradoi
complex.