The genus Xestoleberis (Ostracoda: Xestoleberididae) in the Northern, Northeastern and Eastern regions of the Brazilian continental shelf
Author
Luz, Nathália Carvalho Da
Author
Coimbra, João Carlos
text
Zootaxa
2015
3974
2
177
195
journal article
10.11646/zootaxa.3974.2.3
9de82f14-8d5d-4849-ad25-3bfff43294c0
1175-5326
239624
9BAAB1CC-B92E-482C-9D73-B6415222FED3
Xestoleberis
sp.
Fig. 6
: 12–14
2008
Xestoleberis
sp. 2 Machado, p. 128, pl. 5, figs. 20–21, pl. 6, fig. 1, tab. 6.
Figured specimen.
MP-O-1898.
Locality.
REMAC/Leg 7—Sample 3791 (
12º14’S
/
37º35’W
); depth:
37 m
; sediment: biodetritical sand.
Material.
5 adult
females and
2 juveniles
.
Dimensions.
See table 6.
TABLE 6.
Dimensions of
Xestoleberis
sp.
Material Length (mm) Height (mm) Width (mm) MP-O-1698 (carapace) RV: 0.46 RV: 0.21 0.28 LV: 0.47 LV: 0.24
Description.
A medium-sized and moderately thick-shelled species of
Xestoleberis
. In lateral view, RV subrectangular and elongate; LV sub-ovate and elongate. In dorsal view, sub-ovate and quite inflated. Ventral surface strongly flattened. LV overlapping RV along dorsal, anterior and posterior margins. Maximum length very close to ventral margin. Maximum height at mid-length. Maximum width in posterior third. In RV, anterior margin obliquely pronounced and narrowly rounded ventrally; posterior margin obliquely sloping, somewhat pointed ventrally. Dorsal margin somewhat straight and sloping backward; ventral margin almost straight. In LV, anterior margin obliquely pronounced and narrowly rounded; posterior asymmetrically rounded. Dorsal margin convex; ventral margin convex and somewhat sinuous. Surface typically smooth, with lip-type normal pore canals (
sensu
Sato & Kamiya 2007
). Eye-spot inconspicuous.
Xestoleberis
-spot conspicuous and long. Hinge hemimerodont, with crenulate terminal teeth in RV and median element smooth. Adductor muscle scars a row of four sub-elliptical spots. Frontal scar not well-defined.
Remarks.
Xestoleberis
sp. is a very rare species. In the present paper only seven specimens, consisting of five female adults and two juveniles, were found, hindering a more detailed morphological and taxonomic study. The specimens figured by
Machado (2008)
represent males of this species.
Occurrence and distribution.
Xestoleberis
sp. occurs along the Northeastern and Eastern regions of the Brazilian continental shelf (
Fig. 2
; Tab. 1), between 20 and
79 m
of depth.