Revision of the deep-sea Eulimidae (Gastropoda, Caenogastropoda) from off Northeast Brazil
Author
Souza, Leonardo Santos De
Setor de Malacologia, Departamento de Invertebrados, Museu Nacional-Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Author
Pimenta, Alexandre Dias
Setor de Malacologia, Departamento de Invertebrados, Museu Nacional-Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. & alexpim @ mn. ufrj. br; http: // orcid. org / 0000 - 0001 - 7001 - 5820
alexpim@mn.ufrj.br
Author
Barros, José Carlos Nascimento De
Laboratorio de Malacologia, Departamento de Pesca e Aqüicultura, Universidade Federal Rural de Pernambuco, Recife, PE, Brazil. mundovan 6 @ yahoo. de; http: // orcid. org / 0000 - 0002 - 8476 - 6171
mundovan6@yahoo.de
text
Zootaxa
2021
2021-02-16
4927
4
451
504
journal article
8069
10.11646/zootaxa.4927.4.1
065cd936-3e5f-45f8-ac7f-2d530aab8b4e
1175-5326
4542923
AED51D9E-1751-4010-A8E1-B72AE428821A
Melanella
sp. 2
(
Figure 18
A–F)
Material examined.
Brazil
:
Ceará
: (
03°30′51″S
37°59′28″W
,
384 m
),
RV
Natureza
,
07/xi/2001
:
MNRJ 35267
† [1 dd]
;
Alagoas
: (
10°06′35″S
35°46′41″W
,
720 m
),
RV
Natureza
,
16/xii/2001
:
MNRJ 35206
† [1 dd]
;
Rio Grande do Sul
:
Off Solidão
(
30°46′S
49°07′W
,
176 m
), coll.
RV
Prof. Wladimir Besnard
,
27/i/1972
:
MORG 17624
† [1 dd]
.
FIGURE 17.
A–G.
Melanella
sp. 1: MNRJ 35251. H–J.
Melanella jeffreysi
: lectotype of
Eulima jeffreysi
Tryon, 1886
, USNM 133126. K.
Melanella orphanensis
Clarke, 1974
: holotype, CMNML 66345. D, J. Detail of the teleoconch surface. G. Detail of protoconch, apical view. Scale bars: A–C, H, I, K= 1.0 mm. D= 50 µm. E, F, J= 200 µm; G= 100 µm. Credits: J, courtesy of USNM; K, courtesy of J-M Gagnon (CMNML).
Description.
Shell conical, slightly curved, reaching about
8.5 mm
long,
3.3 mm
wide. Larval shell broken. Teleoconch with about 8.0 whorls, slightly convex outline, convexity accentuated in the lower region of each whorl; suture well demarcated, almost straight; subsutural zone indistinct; surface smooth, incremental scars well demarcated, appearing in intervals of about 1.1 whorl at the last two whorls. Last whorl about 50% of the shell length; base slightly truncated. Aperture high, pear shaped, acute posteriorly and rounded anteriorly; outer lip thin, opisthocline, sinuous, straight near the suture and strongly projecting, reaching the maximum projection at the mid of its height; inner lip thick, sinuous, sloping, reflected and well demarcated. Not umbilicate. Shell vitreous, colorless.
Measurements.
MNRJ 35206†, 8 whorls (apex broken), SL=
8.5 mm
; BWL=
4.5 mm
; AL=
2.8 mm
; SW=
3.3 mm
; AW= 2.0 mm.
Remarks.
The protoconch is broken in the three shells examined, but the relatively wide and solid shell, with a wide aperture and thick inner lip are characteristic enough to be worth noting (
Figure 18
A–F).
Melanella
sp. 2 resembles
M. doederleini
(
Figure 11
A–I) in shape, but has bigger dimensions and a much more elongated aperture. Even with the apex broken, specimens of
Melanella
sp. 2 reaches 8 whorls and
8.5 mm
long, while
M. doederleini
reaches 10 whorls and
3.6 mm
long.
Melanella
sp. 2 can also be distinguished from
M. anapetes
sp. nov.
(
Figure 16
A–G) by the wider aperture, bigger dimensions, thicker inner lip and the curved spire.
FIGURE 18.
A–F.
Melanella
sp. 2: MNRJ 35206. D. Detail of the apex. Scale bars: A–C, E, F= 1.0 mm; D= 500 µm.
Geographical distribution.
Brazil
:
Ceará
,
Alagoas
,
Rio Grande do Sul
(present study)
.
Bathymetric distribution.
From
176 m
to
720 m
.