Taxonomical study on the mollusks collected in Marion-Dufresne (MD 55) and other expeditions to SE Brazil: the Fissurellidae (Mollusca, Vetigastropoda)
Author
Simone, Luiz Ricardo L.
Author
Cunha, Carlo M.
text
Zootaxa
2014
3835
4
437
468
journal article
10.11646/zootaxa.3835.4.2
01da15e5-14ca-4506-89fd-2055b906f4ff
1175-5326
249622
F492B5ED-0CA7-436B-94AF-EE4C99D630AF
Emarginula suspira
new species
Figures 90–102
Emarginula tuberculosa
:
Leal, 1991
: 41
(pl. 2, fig. F);
Rios, 2009
: 27
(fig. 49) (part) (non
Libassi, 1859
).
Emarginula
sp 1:
Leal, 1991
: 42
(fig. 2G).
Types
.
Holotype
MNHN 25310.
Paratypes
: MNHN 25311, 16 shells, MZSP
102932
, 5 shells, MZSP
102939
, 2 shells, MNRJ 25959, 3 shells, all from
type
locality.
Brazil
. Espírito Santo (MD55; Bouchet, Leal & Métivier col); off Itaúnas, continental slope of Abrolhos,
18°59’S
37°48’W
,
607–620 m
, MNHN 25312, 5 shells (sta. DC73;
27/ v/1987
); off Regência,
19°40’S
37°48’W
,
790–940 m
, MNHN 25313, 2 shells, MZSP
102921
, 1 shell (sta. CB77;
27/v/1987
); off Conceição da Barra,
18°58’S
37°49’W
,
637 m
, MNHN 25314, 1 shell (sta. CB76;
27/v/1987
); Jaseur Seamount,
20°27’S
35°54’W
,
54 m
, MNHN 25315, 1 shell (sta. DC34;
15/v/1987
); Montague Seamount,
20°26’S
36°41’W
,
310–350 m
, MNHN 25316, 1 shell (sta. CB79;
14/v/1987
).
FIGURES 100–102:
Emarginula suspira
n. sp.
paratype MZSP 102932 in SEM (L 4.0 mm). Fig. 100: right view. Fig. 101: dorsal-slightly right view. Fig. 102: ventral view.
FIGURES 103–108:
Manganesepta atiaia
,
n. sp
. Fig. 103: paratype MZSP 102946 (L 5.4 mm), dorsal view. Fig. 104: holotype MNHN 25317 (L 3.5 mm), right view. Fig. 105: same, dorsal view. Fig. 106: same, ventral view. Fig. 107: same, ventral-slightly left view. Fig. 108: same, right view, detail of apex (left side = 0.6 mm).
FIGURES 109–115:
Profundisepta denudata
,
n. sp.
,
holotype MZSP 105507 (L 3.0 mm). Fig. 109: dorsal view. Fig. 110: left view. Fig. 111: detail of apex and foramen, dorsal view (upper side= 0.8 mm). Fig. 112: ventral view. Fig. 113: ventralslightly left view. Fig. 114: right view. Fig. 115: detail of apex, right view (L 1.2 mm).
Type
locality.
Brazil
. Espírito Santo; off Itaúnas, continental slope of Abrolhos,
18°59’S
37°50’W
,
295 m
(MD55 sta. DC75; Bouchet, Leal & Métivier col.,
27/v/1987
).
Diagnosis.
Apex greatly curved inwards, located posteriorly, close to posterior apertural lip. Height ca. 40% of length. Sculpted by ca. 40 radial cords, regularly interrupted by concentric, less developed cords, forming nodes at intersections; mostly alternating wide and narrow cords. Slit ca. 30% of shell length.
Description.
Shell size up to
7 mm
; low, limpet-like; height ca. 40% of length. Pure white (Figs 93–95), ca.
10% of specimens with some pale beige pigmentation. Protoconch of 1.5 rounded whorls (Figs 91, 92); situated on right (Figs 94, 97); smooth, glossy; size 230 µm. Slit anterior, rectangular, width ca. 20% of length; opened anteriorly; ca. 8% of shell width and ca. 30% of shell length; edges rather irregular (Figs 93, 95, 96, 98, 99). Profile highly curved ventrally, sagittal profile as arc (imaginary center of ark located below middle point of dorsal surface, ca. 20% away from aperture) (Figs 94, 97); beak located close to posterior margin of aperture. Sculpture of ca. 40 narrow radial cords (Figs 90, 93, 97, 99–101); gradually more distinct towards aperture, wide and narrow cords disposed intercalating, narrow cords ca. 1/2–1/4 of wider cords (Figs 90, 93, 96, 99); concentric cords regularly distributed from apex to aperture (
Figs 100–101
), ca. 1/2 to 1/3 width of primary radial cords; nodes at intersection of radial and concentric cords low in some specimens (Fig. 99), but frequently forming spine-like projections about as thick as cords (Figs 90, 93, 96); interspaces twice as wide as primary cords, covered by concentric sculpture; interval between concentric sculpture approximately twice as wide as threads; median threads with ca. 40 concentric cords; well preserved specimens with periostracum forming additional transverse, wide pits in concavity formed by radial and concentric cords (Fig. 99). Selenizone well-marked, edges sharp, as tall as adjacent radial cords; lunules regularly distributed (Figs 90, 93, 96, 99. 100). Aperture planar (Fig. 94) to slightly concave (Fig. 97), outline elliptical, width ca. 70% of length; edges undulating due to radial cords; posterior lip flattened, planar, ca. 20% of shell length; mostly convex (Fig. 95), rarely concave (Fig. 98). Inner surface smooth, glossy; apex cavity moderately deep, ca. 20% of shell length (Figs 95, 98, 102).
Measurements (in mm).
Holotype
: 6.8 by 2.9;
paratypes
MNHN 25311 (Fig. 96): 3.9 by 1.6; MNHN 25315 (sta. 34, Fig. 99): 2.7 by 1.4; MZSP
102932
: #1, 5.0 by 2.7 (Fig. 90), #2, 4.0 by 1.7 (
Figs 100–102
).
Distribution.
Continental slope off Espírito Santo,
Brazil
.
Habitat.
Sandy-mud bottoms,
54–940 m
(dead shells).
Material examined.
Types
.
Etymology.
The specific epithet is derived from the Portuguese word
suspiro
, a special dessert, a candy done with egg albumin and sugar; an allusion to general appearance of the shell somewhat resembling this delicate candy. The noun is in apposition.