Bulletin Zoologisch Museum
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Vol. '4 No. 12 29-IV-1975
Marginella orstomi, a new species from deeper water off the coast of West Africa
H.E. Coomans
Abstract (Nicklès, 1950: 118-122; Knudsen, 1956: 81-93).
Clover (1972) described Marginella huber ti from Marginella (s. str.) orstomi nov. spec. was col- lected at of 200 to off Pointe A related a depth 250 m, LobitOj Angola. species was dredged re-
Noire, Congo. The species is related to M. huberti cently from a more northern locality off the coast Clover, 1972, from Angola. Both species have a
characteristic white tooth on the inside of the of Congo Brazzaville.
outer lip near the posterior end.
orstomi Marginella nov. spec. Figs. 1-3.
INTRODUCTION
Shell medium Description.- sized, elongate pear-
The marine malacofauna of West Africa is rich in shaped, whorls; ground colour dirty yellow
with Marginellidae. Although many authors recognize on- dark areas, and many dark grey transverse ly one genus, Marginella Lamarck, 1799, in my opin- irregular zigzag lines sometimes crossed by spi-
the of at least ion family consists fourty recent ral rows of small dots ; apex sharp, angle of spire genera and subgenera (Coan, 1965; Coomans, 1975). about 70°; aperture straight and rather narrow,
The of str. about of the of the the of distribution Marginella s. (type spe- J length shell, design
Voluta cies glabella Linnaeus, 1758) is confined the last whorl is visible on the inside of the ap- to West and South Africa. About twenty species of erture; outer lip thickened and deflected outward,
str. known from West transversal Marginella s. are Africa on the outside about 30 to 35 grey 100
almost within to M. huberti which stripes are present, smooth and with Clover, 1972, was collected
one tooth near the posterior end; four white more southward on the coast of Angola. Both spe-
white oblique folds on the anterior half of the colu- cies are characterized by the presence of a
mella. tooth on the inside of the outer lip near the pos-
terior end. Some differences in the shell of both Dimensions (in mm) length width
28.0 here: holotype (adult, fig. 1) 15.1 species are mentioned paratype (adult, fig. 2) 23.lt 12.5
paratype (juvenile, fig. 3) 12.3 M. huberti M. orstomi
length 17 - 19 nun 23 - 28 mm 80° 66° apical angle - 87° - 72° Type locality.- Atlantic Ocean, off the coast of outer lip dentate smooth from Pointe Noire, Congo, depth 200-250 m. Dredged stripes on outer lip about 20 about 30 "André December the ship Nizary" (0RST0M) on 5
1972.
The holotype and two paratypes are present in the
collection of the Zoologisch Museum, University of
Amsterdam. ACKNOWLEDGEMENTS
Etymology.- The species is named after the French The author wishes to thank Mr. W. Bergjnans of the
his organization 0RST0M (= Office de la Recherche Department of Manuals of our Institute for do-
Scientifique et Technique Outre-Mer) under whose nation of the type material of Marginella orstomi,
supervision the dredgings were performed. together with other mollusks from West Africa, to
the Zoologisch Museum, University of Amsterdam.
orstomi Remarks.- Marginella belongs to the genus The photographs were taken by Mr. L.A. van der
Marginella s. str. The species is closely related Laan.
REFERENCES
COAN, E., 19Ô5- A proposed reclassification of van het tienjarig bestaan van de Malacologische
the family Marginellidae. Veliger, 7 Contactgroep Amsterdam en Omstreken: 7-18, pis.
figs. 1-9- 1-2.
CLOVER, P.W., 1972. Two new species of Marginel- KNUDSEN, J., 1956. Marine prosobranchs of tropi-
lidae from West Africa. J. Conch., 27: 503—50U, cal West Africa (Stenoglossa). Atlantide Rep.,
pi. XIX. 7-110, pis. I-IV.
de COOMANS, H.E., 1975- Historie en systematiek van NICKLÈS, M., 1950. Mollusques testacés marins
de la côte occidentale Manuels Ouest-Afr. Marginellidae (Gastropoda). Malacologische Op- d'Afrique. , stellen In: Feestbundel uitgegeven ter gelegenheid 2: 1-269, figs. 1-U59.
Dr. H.E. Coomans
Instituât voor Taxonomische Zoologie
(Zoologisch Museum) Universiteit van Amsterdam
Plantage Middenlaan 53
Amsterdam, The Netherlands.
Received: March 6, 1975 101
stomi from off Pointe Marginella or nov. spec, Noire, Congo.
1. Holotype, length 28.0 mm.
2. Paratype, length 23-4 mm.
3. Paratype (juvenile), length 25 mm.