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
Turricostellaria amphissa
n. sp.
(
Fig. 5
A-D)
TYPE MATERIAL
. —
Holotype
:
Brazil
,
Espírito Santo
, off Itaúnas, continental slope of Abrolhos,
18°59’S
,
37°50’W
,
295 m
depth,
MNHN
25230 (
Fig.5A
) (
MD
55, stn
DC
75, Bouchet, Leal & Métivier coll.,
27.
V
.1987
).
Paratypes
: same data as
holotype
,
MNHN
25231, 2 shells (
Fig. 5B, C
),
MZSP
102691, 2 shells (
Fig. 5D
).
TYPE
LOCALITY
. —
Brazil
,
Espírito Santo
, off Itaúnas, continental slope of Abrolhos,
18°59’S
,
37°50’W
,
295 m
depth (
MD
55, stn
DC
75).
DISTRIBUTION. — Known only from
type
locality.
ETYMOLOGY. — The specific epithet refers to the similarity of the species in fashion and size with columbellid genus
Amphissa
H. & A. Adams, 1853.
DIAGNOSIS. — Shell up to
5 mm
, wide (width
c.
half length). Sculpture axial, strong; shoulder narrow. Protoconch wide, paucispiral.
DESCRIPTION
Shell: size up to
5 mm
, outline oval; width
c.
48% of length. Colour pure white, translucent. Protoconch mammillate, comprising
c.
15% of shell length and
c.
35% of shell width;
c.
1.5 rounded, smooth, glossy whorls; suture plane (
Fig. 5B, C
); transition with teleoconch unclear. Spire
c.
50% of shell length, spire angle
c.
40°. Teleoconch up to three glossy whorls; each whorl with narrow shoulder, remaining weakly convex. Sculpture of strong axial threads, slightly arched, from suture (shoulder) to suture;
c.
12 in
penultimate whorl; interspaces of axial threads roundly concave, with
c.
double threads width. Ventral region of body whorl with inferior ⅓ lacking spiral threads (
Fig. 5A, D
), with axial threads disappearing gradually. Aperture elliptic, weakly oblique; comprising
c.
50% of shell length and
c.
40% of shell width. Outer lip simple, rounded, lacking folds. Inner lip slightly concave, lacking callus; four oblique folds uniformly distributed in middle region, comprising
c.
60% of inner lip area; upper and inferior folds smaller than second and third folds (
Fig. 5A, D
). Canal narrow, somewhat pointed, slightly projected forwards. No umbilicus.
MEASUREMENTS (in mm). —
Holotype
: 4.6 × 2.1;
paratype
MNHN 25231
: 4.4 × 2.2;
paratype
MZSP 102691
: 3.6 × 1.6.
HABITAT. — Sandy-mud bottoms,
295 m
depth.