Description of a new species of the genus Haustellum Schumacher, 1817 (Gastropoda: Muricidae) from the Western Indian Ocean

4 Pages·1993·1.4 MB·English

L. BOZZETTI Haustellunfranchii APEX 8(3),juillet 1993
Description of a new species of the genus Haustellum Schumacher,1817
(Gastropoda: Muricidae) from the Western Indian Océan.
BOZZETTI
L.
V. Devoto, 3 - 20133 Milano - ITALY
KEYWORDS:
Gastropoda, Muricidae, Haustellum franchii n.sp., Somalia.
,
ABSTRACT: An undescribed species belonging to the genus Haustellum has been
found in deep water off the most northeastern point of Africa; a comparison is made
withtheclosestspecies includedinthe "group" ofHaustellum s.s.
INTRODUCTION. appropriate, ifconfirmed by further studies, to
give them anofficiai taxonomic status.
The genus Haustellum shows a close
relationship with Murex s.s. Linné,. 1758, and
in the PONDER & VOKES (1988) revision of Haustellumfranchii n. sp.
the Indo-West Pacific species of the two
gênera, the authors ascribed to Haustellum Description
certain species previously included by other Shell moderate in size for the genus, club-
taxonomists ( e.g. Radwin & D' ATTHiO, shaped, low-spired, protoconch paucispiral of
1976; FAIR, 1976) in the genusMurex s.s. one and one half to two smooth, bulbous
The main différence between the two taxa whorls, terminating in a straight, marked varix
has been foundinthe reproductive System the and followed by six convex, rounded
:
species of Haustellum show a non-muscular postnuclear whorls. Suture impressed and
ejaculatory duct, whereas the species ofMurex weakly undulate, three rather strong, rounded
hâve a muscular one (PONDER & varices per whorl, noticeable from third
VOKES,1988:10, 17). teleoconch whorl onwards, excavated behind,
As well the shell body présents some spineless on body whorl, with a small spine-
différences, the lack of labral tooth and the Uke tubercle on shoulder of spire whorls. Four
spineless (or almost spineless) varices are or five axial costae in each intervarical space,
typical for the genus Haustellum (PONDER & weak axial ribs discontinuously distributed
VOKES, 1988 : 7, 14, 17). Nevertheless, between them; four spiral cords per whorl on
Haustellum sensu Ponder & Vokes can be first two teleoconch whorls, afterwards minor
easily divided, according to several shell cordlets appearing, alternating with principal
characters, in two distinctive groups: a first ones, for atotal of26/30on body whorl; spiral
one including low spired species with globose continuing on higher half of siphonal canal.
and spineless body whorl, very developed Primary cords, crossing axial costae, generate
inductura, long and smooth, or nearly so, prominent and rounded tubercles, stronger on
siphonal canal, and a second group including shoulder edge. Aperture obliquely ovate, anal
the species moved by PONDER & VOKES notch broadly open and shallow, labrum
(1988) from Murex s.s. to Haustellum. protruding, sharply edged and weakly
HOUART (1990 331), making tfiis division, crenulate, with a small hollow prickle at
:
dénommâtes the first group Haustellum s.s. posterior end just following apertural varix.
and the second Haustellum s.l.; it would be Inner side of outer lip with 13-15 lirations,
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APHX
8(3),juillet 1993 Hausiellunfrancfm L. Bozzetti
columcllar lip adhèrent posteriorly and siphonal canal, someUme présent also in H.
detatched anteriorly, forming an highly haustellum, is much more developed and in
developed induetura, outside sculptured willi more anterior posihon than H. franchii one.
swollen ribs, sniooth inside. Siphonal canal Twoother taxa included in the Haustellum s.s.
straighi, moderately long, just less than hall'of group H. kurodai (Shikama, 1964) and H.
:
total shell length, narrowly open and viedani Kosuge, 1980, from Japan and the
conimunicating with stomatic aperture trough PhiUppines, hâve been synonymized by
a sinuous slit, one small spine présent near PONDER& VOKES (1988) with H. haustellum.
base ofbody whorl, surface nodose. A rare species from south west Australia, H.
Ground colour creani with dark brown and wilsoni D'AttiUo & Old, 1971 has a certain
reddish-brown spiral Unes, from fourth Ukeness in shape with the new species, but
teleoconch whorl onwards, and topping differs in its pustulose sculpture, morerounded
primary cords; first Une on shoulder edge, a shoulder, deep channelled suture and ground
second one, noticeable on penultimate whorl, colours.
just over suture; on body whorl : one on HOUART (1990 : 333, fïgs. 14-16, 32)
shoulder edge, two adjacent just under mentions a probably undescribed species of
midbody Une and one on basai zone; pattern Haustellum found in Tanzania and
conUnuing on spiral sculpture of siphonal Madagascar waters, but it has very différent
canal. Aperture withish, inner Up edge inside features (in shape, colour and sculpture) from
reddish coloured; brownish bands on siphonal H. franchii. H. hirasei (Hirase, 1915) has an
canal regularly distributed. almost identical colouration and pattern, but
this taxon belongs toHaustellum s.l. group.
Comparison
H. franchii falls under the Haustellum s.s. Type Locality
group; few species and subspecies belonging Trawled by shrimp boats at 200-250m depth
to this group are présent in the western side of offRas Hafun, northeastern SomaUa.
the Indian océan, namely H. haustellum
:
haustellum (Linné,, 1758) with a wide Indo-
Pacific distribution, H. haustellum Type Material
longicaudum (Baker, 1891) probably Umited Three spécimens studied holotype,
:
to the Horn of Africa area, including southern 59.80mm, IRSBN, Bruxelles, no. 27962/459;
part of the Red Sea, H. fallax (Smith, 1901) paratype 1, 66.85mm, F.Franchi Col.,
from Natal to Mozambique. Piacenza; paratype 2, 30.30mm,R. Houart
The new species differs from the first two Col., Ezemaal.
above mentioned because of its lower spire,
more rounded whorls profile, Ughter
colouration lacking blotches; H. fallax has a Etymology
similar low spired shells, but with a more I dedicate this species to Dr. Fabrizio
angled shoulder, heavier and broader varices Franchi from Piacenza, a keen conchologist
and axial ribs, darker ground colour and and agreat friend.
différent pattern, moreover the spine on the
Figures 1-8 (opposite)
1. H. franchii, holotype, 59.8mm. 2. H. franchii, paratype 1, 66.85mm. 3. H. haustellum
haustellum, 120mm, Mactan Isl., Philippines; 4. H. viedani, 130mm, Bohol Isl., Philippines; 5. H.
kurodai, 120mm, Siasi Isl., Sulu Sea, Philippines; 6. H. hirasei, 63mm, Tosa Bay, Japan; 7. H.
wilsoni, 72.5mm, Freemantle, W. Australia; 8. H. fallax, 79.5mm, off Durban, S. Africa.
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L. BOZZETTI Haustellunfranchii APEX 8(3),juillet 1993
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APtiX 8(3).juillet 1993 Hausiellunfranchii L. BozzErn
ACKNOWLEDGEMENTS. HOUART, R., 1990. New taxa and new re-
cords of Indo-Pacific species of Murex and
I would like 10 thank the Società Italiana di Huustellum (Gastropoda, Muricidae, Murici-
Malacologia, Milan department for making nae). Bull. Mus. natn. Hist. nat., Paris, 4 s,r.,
their library and instruments available, Mr. 12, sect. A, no. 2 329-347.
:
Aldo Bianchi l'rom Milan l'or taking the
pictures of the Holotype, and Mr. Hassan PONDER, W. F., & E. H. VOKES, 1988. A
Mohamed Jumale (Testa), from Mogadishu, revision of the Indo-West Pacific Fossil and
an envaluable collaborator. Récent species of Murex s.s. and Haustellum
(Mollusca Gastropoda Muricidae). Rec
: :
REFERENCES. Aust. Mus., Suppl. 8 1-160.
:
FAIR, R. H., 1976. The Murex Book, an RADWIN, G. E., & A. D" ATTILIO 1976.
illustrated catalogue of Récent Muricidae. Murex shells ofthe world. An illustrated guide
(Muricinae, Muricopsinae, Ocenebrinae) to the Muricidae. Stanford, 1-284.
Honolulu: 1-138.
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