The family Pyramidellidae Gray, 1840 (Mollusca, Gastropoda, Heterostropha) in West Africa. 5. Afroturbonilla hattenbergeriana n. gen. n. sp

5 Pages·1999·2.9 MB·English

by  Anselmo Peñas

SociedadEspañoladeMalacología /¿'^rwj, Suplemento 5: 201-205, 1999
The family Pyramidellidae Gray, 1840 (MoUusca, Gastro-
poda, Heterostropha) inWest África. 5. Ajroturbonilla hat-
tenbergeriana n. gen. n. sp.
La familia Pyramidellidae Gray, 1840 (MoUusca, Gastropoda,
Heterostropha) en África Occidental. 5. Afroturbonilla hattenberge-
rianagen. nov. spec. nov.
Anselmo PEÑAS*, Emilio ROLAN** and Christoffer SCHANDER***
Recibidoell-VI-1999.Aceptadoel15-IX-1999
ABSTRACT
A new genus, Afroturbonilla, and a new species, A. hattenbergeriana, belonging to the
family Pyramidellidae are described from the West África coast. The shell and the most
important morphological characters of the shell are represented. A comparison with rela-
ted genera and species is made.
RESUMEN
Se describe un nuevo género Afroturbonilla, y una nueva especie, A. hattenbergeriana,
de la familia Pyramidellidae de la costa occidental de África. Se representan la concha y
los más importantes caracteres morfológicos de la misma, estableciéndose una compara-
ción con los géneros próximosyespecies más similares.
KEY WORDS: Pyramidellidae, Afroturbonilla hattenbergeriana, new genus, new species, West África,
Paradoxella,Styloptygma,Syrnolina.
PALABRAS CLAVE: Pyramidellidae, Afroturbonilla hattenbergeriana, nuevo género, nueva especie, África
Occidental,Paradoxella,Styloptygma,Syrnolina.
INTRODUCTION
In a series ofpapers the authors are therefore erect a new genus, Afroturbo-
revisingthefamilyPyramidellidaefrom nula, to containthis species.
West África. Complete references to
these works canbe found in a previous
paper (Peñasand Rolan, L998). In the MATERIALANDMETHODS
present paper we describe a new
species that could not be assigned to SeePeñasandRolan(1998)andthe
any previously described genus. We firstworkinthepresentsupplement.
*CarrerOlérdola,39, 5°C,E-08800VilanovailaGeltrú, (Barcelona), SPAIN
**CánovasdelCastillo,22,E-36202Vigo, Pontevedra,SPAIN
***WoodsHoleOceanographicInstitution,RedfieldLaboratory1-44MS#34,WoodsHole,MA02543,USA
201
Iberus, Suplemento 5, 1999
RESULTS
Family Pyramidellidae Gray, 1840
GenusAfroturbonilla n. gen.
Typespecies:Afroturbonillahattenhergerianan.sp.
Diagnosis: Shell slender, fragile, midella {Styloptygma) typica Tryon, 1866
conoid in initial whorls and cylindrical owing tohomonymy This is incontrast
in later ones. A well-defined umbilicus to SCHANDER, AaRTSEN AND CORGAN
is surrounded by a distinct, prominent (1999) that considered Styloptygma and
spiral ridge. Sculpture ofweakaxial ribs Paradoxellasepárategenera.Afroturbonilla
alsocoveringthespiralridge. is also similarto the type species ofSyr-
Etymology: Afro-, which relates to nolina Dalí andBartsch, 1904, Odostomia
África, and Turbonilla, a genus of Pyra- rubraPease, 1868,byoriginaldesignation.
midellidae. Thetype species ofStyloptygmahas a
Remarks: ThegenusAfroturbonillahas shell with a deeper suture and more
a superficial resemblance to the type convexwhorls. Thetype species orPara-
species ofthe genusParadoxella Laseron, doxella is more uniformelly elongate,
1959, Paradoxella ambigua Laseron, 1959, with asmallerlastwhorl. Thethreetype
by original designation. We here agree species of the genera Styloptygma, Para-
withShigeoHori (personal communica- doxella and Syrnolina are smaller in size
tion)thatParadoxellaisasynonymofSty- and they are all lacking an umbilicus
loptygmaA. Adams, 1860, with the type and the distinct ridge surrounding it,
species, Monoptygma stylinaA. Adams, and have a different profile thatAfrotur-
1853, by original designation. The type bonilla. All known species of these three
speciesofStyloptygmawasrenamedPyra- generaarefromthePaciñcOcean.
Afroturbonilla hattenhergeriana n. sp. (Figs. 1-12)
Typematerial:Holotype (Fig. 1), specimenwithdriedsoftpartsinside; and4paratypes(2juve-
nile and 2 fragments); from 20 m, Cacuaco, Bengo, Luanda, Angola, deposited in the Museo
Nacional de Ciencias Naturales, Madrid (Accessionnumber 15.05/33303). Additionalparatypes
are placed in the following institutions: 1 shell and 2 fragments from25 m, Dakar, Senegal, in
MuséumNationald'HistoireNaturelle, Paris;2juveniles, onefrom2m. ClubNautique, Congo,
andanotherfrom2m, PointeIndienne, Congo,incollectionofP. H. Hattenberger; 1 shelland 1
juvenile,from20m, Palmeirinhas, Luanda,Angola,incollectionofA. Peñas; 1 shell,2juveniles,
5 fragments, intertidal, Banc d'Arguin, Mauritania, and4juveniles (Fig. 2), from30 m, Miamia,
Ghana,incollectionofE.Rolan;3juveniles,Dakar,Senegal,incollectionofJ.Pelorce.
Typelocality:Cacuaco,Luandaárea,Bengoprovince,Angola.
Etymology:ThespeciesisnamedinhonorofPaulHenriHattenbergerwhohascollectedsomeof
thematerialofA.hattenbergeriwhokindlyputhiscollectionofWestAfricanshellsatourdisposal.
(Right page) Figures 1-7. Afroturbonilla hattenhergeriana n. sp. 1: Holotype (MNCN), Cacuaco,
Angola;2:juvenileshell,Miamia, Ghana;3:detalloftheapertureofajuvenileshell;4: detailofthe
internal part ofthe columella, Congo; 5: protoconch, Senegal; 6: protoconch, Ghana; 7: proto-
conch andfirstwhorls,Angola.
(Página derecha) Figuras 1-7. Afroturbonilla hattenhergeriana spec. nov. I: Holotipo (MNCN),
Cacuaco, Angola;2: conchajuvenil, Miamia, Ghana;3: detalledelaabertura de una conchajuvenil;
4:detalledelaparteinternadelacolumela, Congo;5:protoconcha, Senegal; 6:protoconcha, Ghana; 7:
protoconchayprimeras vueltas,Angola.
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PeñasETAL.-. PyramidelliclaeofWestÁfrica.Áfroturbonillahattenbergerianan. gen. n. sp.
203
Iberus, Suplemento 5, 1999
Figures8-12.Afroturbonillahattenbergerianan.sp. 8: protoconch, Ghana; 9: microsculptureonthe
sixthwhorl (holotype); 10: microsculptureonlastwhorl (holotype); 11: apertureofajuvenileshell,
Dakar, Senegal; 12: apertureoftheholotype.
Figuras8-12.Afroturbonillahattenbergerianaspec. nov. 8:protoconcha, Ghana;9:microsculturadela
sexta vuelta (holotipo); 10: microscultura de la última vuelta (holotipo); 11: abertura de una concha
juvenil, Dakar, Senegal; 12:aberturadelholotipo.
Description: Shell (Fig. 1) cylindric- towards A (in the classification of
conoid elongate with a sharp apex, Aartsen, 1987), planispiral and 250 ¡¿m
fragile, slightly translucent and whitish. in diameter, showing one whorl with
Protoconch (Figs. 5-8) small in relation visible nucleus partially sunk into teleo-
to the size ofthe shell, oftype B tending conch. Teleoconchbeginning with 5 or6
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PeñasETAL.-. PyramidellidaeofWestÁfrica.Afroturbonillahauenbergerianan. gen. n. sp.
smooth whorls (Figs. 1, 2, 6), increasing folds. The curvature is slightlyirregular,
quickly in diameter giving the shell a extending both to the base and to the
cortical shape. Thereafter numerous external part of preceding whorl. The
axial riblets appear, weakly marked and micro-sculpture is not readily visible in
slightly irregular. The subsequent\l-2 the initial teleoconch whorls, but a
whorls increase regularly in diameter rough surface is visible inhigh magnifi-
but the foUowing keep the same diame- cation in the following whorls (Fig. 9).
ter giving the shell a cylindrical profile. This surface is formed by many micros-
The last whorl represents one-third of copie depressions. In the subsequent
the total shell length and has a strong whorls there are axial undulations
cordsurroundingtheumbilicusnearthe betweenandontheaxialribs (Fig. 10).
base. Umbilicus isnarrowbutdeep. The Dimensions:Theholotypeis 14.3x3.8
cord is present also in juvenile shells mm.Anothershell, destroyedduringthe
mm
(Figs. 2, 3), being then less marked, and study,reached 15 inheight.
becoming stronger with growth (Figs. Distribution: This is a rare species.
11, 12). Aperture is semicircular and Shells and shell fragments have been
slightly pyriform. The visible partofthe foundfromMauritaniatoAngola.
columella is slightly undulating and Discussion: There is no African
without any fold. Columellar fold is species with a profile similar to Afrotur-
visible in juvenile specimens, and a bonilla hattenbergeriana. Juvenile shells
well-demarcated prominent fold is can resemble species of shells belonging
present on the internal part of the colu- to the genus Syrnola A. Adams, 1860,
mella inbroken shells (Fig. 4). Outer lip butthepresenceofanumbilicusandthe
is smooth, narrow and without any surroundingcord differentiatethem.
ACKNOWLEDGEMENTS
We are in debt to the following ítaloNofroni andtwo anonymousrevie-
persons whohave collected the material wersfortheirsuggestions.
used in this study: J. Templado, F. This is contribution number 10010
Rubio, M. Calvo, C. Álvarez, Pelorce, from the Woods Hole Oceanographic
J.
F. Fernándes, M. Pin and P. H. Hatten- Institution.
berger. We thank Jesús Méndez of the This research has been partially
CACTI, Vigo University, for taking the suported by the project XUGA
SEM photographs and Shigeo Hori, 30114A96.
BIBLIOGRAPHY
Aartsen, van,1987.EuropeanPyramide- SCHANDER,C,VANAaRTSEN, ANDCORGAN,
J.J. J.J.
llidae: III Odostomia and Ondina. Bollettino J.X, 1999.FamiliesandGeneraofthePyra-
Malacologico,23: 1-34. midelloidea(Mollusca:Gastropoda). Bollet-
Peñas,A.andRolan,E.,1998.LafamiliaPy- tinoMalacologico(inpress).
ramidellidaeGray, 1840 (Mollusca, Gastro-
poda,Heterostropha)enÁfricaOccidental.
3.ElgéneroChrysallidas.LIberus,suplement
4:1-73.
205