Vol. 99 (2-3)
April 29, 1985
THE NAUTILUS 45
ARENE FLEXISPINA. A NEW SPECIES (GASTROPODA: LIOTIIDAE)
FROM OFF EASTERN BRAZIL
Jose Henrique N. Leal 1 and Arnaldo C. dos Santos Coelho
Setor de Malacologia 2 -Museu National
20.942 -Rio de Janeiro, RJ -Brasil
Seven species of the genus Arene H. & A.
Adams, 1854 are already known from the Brazil-
ian coast: Arene tricarinata (Stearns, 1872), A.
briareus (Dall, 1881), A. variabilis (Dall, 1889),
A. bairdii (Dall, 1889), A. brasiliana (Dall,
1927), A. riisei Rehder, 1943 (Abbott, 1974;
Rios, 1975) and A. notialis Marini, 1975 (Marini,
1975). The present description is based on speci-
mens obtained through bottom sampling (van
Veen and Petersen grabs) between 54 and 82
meter depth during the GEOMAR X cruise
undertaken by the Brazilian Navy research
vessel "N.Oc. Almirante Camara" along the
eastern coast of Brazil, in the period of 01-11
June 1978. Sampled substrate in the three sta-
tions where the species was found consisted of
fragments of calcareous algae and calcareous
gravel. Although soft parts are not preserved,
thus making difficult a more accurate taxonomic
characterization, shell features are markedly
distinct.
Arene flexispina new species
(Figs. 1-3)
Description: Shell small, solid, trochoid in
shape, reddish brown, with spiral rows and
spines of lighter color. Ratio height/width of the
shell higher in adults than in younger speci-
mens. Whorls 5V2, the first IV2 comprising the
protoconch, white and smooth, lower than the
subsequent whorl. Teleoconch whorls with 2
larger peripheral spiral rows of 10 or 11 large,
fluted spines spirally raised and imbricated.
Narrower row 1-2 subsutural, one intermediate
(between the 2 larger) and one immediately
above the subsequent whorl, with numerous im-
bricated scale-like spines, smaller than those in
the 2 larger rows. Finely incised axial lines on
entire shell microscopic and crowded. Suture
'Present address: B.L.R., Rosenstiel School of Marine and
Atmospheric Science, 4600 Rickenbacker Causeway, Miami,
FL 33149
Contribution no. 46
channeled, clearly defined. Body whorl rounded,
with wider spiral cords; spines in the 2 larger
cords triangular, bent outwards and sharply
pointed in apical view; spines number the same
as in the spire. Base with 4 or 5 well-separated
beaded spiral cords; beads almost imperceptible
in worn specimens. Cord bordering the umbili-
cus the same size or only slightly larger than the
other basal cords (younger specimens). Um-
bilicus wide, deep and twisted, with fine axial
lines internally. One or two cords entering the
umbilicus in younger shells, absent in mature
specimens. Aperture whitish, oblique. Outer lip
thin, with crenulations corresponding to the ex-
ternal spiral ornamentation. Operculum round,
multispiral, with small radial lines giving beaded
aspect to its calcareous external surface.
Attachment side horny and convex.
Material examined: GEOMAR X station 048,
40 km off Ponta de Corumbau, Bahia, Brazil
(16°56'30"S, 38°39'30"W), 80 m depth, "N.Oc.
Almirante Camara" col. 09 June 1978, Holotype,
Museu National, Rio de Janeiro, Brazil (Col.Mol.
MN 5352), height 6.4 mm, width 6.7 mm; Para-
type 1, United States National Museum, Wash-
ington, D.C. (USNM 820786), height 5.4 mm,
width 6.2 mm; Paratype 2 (Col.Mol.MN 5353),
height 4.7 mm, width 5.4 mm; Paratype 3,
Museu Oceanografico, Fundacao Universidade
do Rio Grande, Rio Grande, Brazil (MORG
22807), height 3.5 mm, width 4.5 mm; Paratype
4 (USNM 820786A), height 3.4 mm, width 4.3
mm; Paratype 5 (MORG 22808), height 3.2 mm,
width 4.3 mm; GEOMAR X station 038, 170 km
off Conceicao da Barra, Espirito Santo, Brazil
(18°49'00"S, 37°52'00"W), 54 m depth, "N.Oc.
Almirante Camara" col. 07 June 1978, Paratype
6 (MORG 22619), height 2.0 mm, width 3.0 mm;
GEOMAR X station 047, 120 km off Abrolhos
Reef, Bahia, Brazil (17°44'00"S, 37°21'00"W), 54
m depth, "N.Oc. Almirante Camara" col. 08
June 1978, Paratype 7 (Col.Mol.MN 5354),
height 1.4 mm, width 2.4 mm.
BioStor
