Contr. Tert. Quatern. Geol. 34(1-2) 47-49 1 fig. Leiden, March 1997 Austriumphis, a new genus of buccinid gastropods from the Pliocene of South Africa Geerat J. Vermeij University of California Davis, U.S.A. Geerat from Pliocene of South Africa. — Contr. Tert. Quatern. Vermeij, J. Austriumphis, a new genus of buccinid gastropods the Geol., 34(1-2): 47-49,1 fig. Leiden, March 1997. of Africa. The is for dilemma Kilburn & Tankard, 1975, from the Pliocene South This genus Austriumphis proposed Triumphis early the Photinae differs in shell characters from species, which may belong to buccinid gastropod subfamily Gray, 1857, many Triumphis is a member of the Gray, 1857, whose only species, the tropical eastern Pacific Buccinum distortum Wood, 1828, Recent Pseudolividae Cossmann, 1901. Key words — Pliocene, South Africa, Buccinidae, new genus. Prof. Dr G.J. Vermeij, Department of Geology and Center for Population Biology, University of California, Davis, CA 95616, U.S.A. Contents SYSTEMATICPART 47 Introduction p. Order Neogastropoda Systematic part p. 47 Family Buccinidae Latreille, 1825 49 Acknowledgements p. Genus Austriumphis nov. gen. 49 References p. Type species — Triumphis dilemma Kilburn & Tankard, 1975. Introduction Etymology — Combination of the Greek prefix austro- (southern) and the genus name Triumphis; by happy The early Pliocene molluscan fauna of South Africa coincidence, the German preposition 'aus' means 'out contains a number of enigmatic species that have been of', implying that the new genus was taken out of to One of these is the to which its had questionably assigned living genera. Triumphis, genus type species Triumphis dilemma Kilburn & Tankard, 1975. In previously been assigned. reviewing all living and fossil genera of the Diagnosis — Shell of medium size, maximum height have examined of neogastropod family Pseudolividae, I 30.6 mm, ovate. Spire of teleoconch consisting at Buccinum distortum Wood, 1828 (the Recent tropical least five whorls, which are separated by a shallow, last whorl eastern Pacific type species of Triumphis Gray, 1857) as appressed suture. Spire relatively high, well as the South African T. dilemma. The two species comprising two-thirds of total shell height. Whorls in lateral last whorl not clearly do not belong to the same genus or even the same evenly convex profile; family. Whereas T. distorta is a member of the constricted above siphonal canal. Siphonal canal very Pseudolividae(Vermeij, in prep.), T. dilemmabelongs to short, with deep anterior notch. Spiral ornament 11 here is to the new of fine, spaced cords, 9 to on the Buccinidae. My purpose propose consisting evenly whorl, 24 to 27 on last axial genus Austriumphis for T. dilemma, and to discuss the penultimate whorl, with possible relationships of the South African fossil to other sculpture absent. Outer lip smooth, polished edge, buccinids. lower one-third of outer lip forms very shallow, broad 48 horizon and maintained its sinus. Medial sector of outer lip convex when viewed at Hondeklip Bay, original ventrally; weak posterior notch present where adapical placement in Triumphis. The deposits at Langebaanweg end ofouter lip joins penultimate whorl at low angle. and Hondeklip Bay from which this species comes are Pether, now thought to be of early Pliocene age (J. pers. comm., 1995). Characters of external ornament, the columella, and and the outer lip set this species apart from Triumphis from all other members of the family Pseudolividae. Spiral ornament in Austriumphis is evenly distributed over the last whorl from the suture to the base, and shows no indication of coarsening towards the base as it does in Triumphis and all other pseudolivids. The columella of Triumphis is smooth, and bears a weak fold at the entrance to the siphonal canal. In Austriumphis, the columella is excavated and lacks the basal fold. Instead, it bears three small basal folds. The outer lip of has and Triumphis and other Pseudolividae a sharp edge indicates indeterminate growth, whereas that of Austriumphis is smooth and polished and implies sector of the outer of determinate growth. The upper lip Austriumphis flares slightly, i.e. it is abaxially slightly expanded and ascends the spire slightly relative to earlier stages of growth. These characters conform to Vermeij & Signor's (1992) criteria for a unique adult lip, which indicates determinate growth in Austriumphis. The ventral profile of the outer lip also differs in the two Fig. 1. Austriumphis dilemma (Kilburn & Tankard, 1975), is genera. In Triumphis and other Pseudolividae, the lip early Pliocene, Hondeklip Bay, South Africa (South when viewed whereas in Austriumphis African Museum PQAV 945), apertural (a) and dorsal planar ventrally, sinus its lower (b) views, x 2. the lip bears a very shallow, concave on The inner side of the third, and a medial convex sector. Upper sector of outer lip in adult abaxially slightly outer lip is marked by a deeply recessed ridge parallel to expanded and adapically extended; inner side of outer lip the outer edge in Austriumphis. No comparable ridge is with recessed which is marked 14 short other deeply ridge, by known in Triumphis or any pseudolivids. somewhat excavated; of lirae. Inner lip adherent, margin No named genus closely resembles Austriumphis. columella sinuous, ornamented on lower part by three The absence of axial ornament, the presence of lirae on end of inner very weak folds. Adapical lip bearing the inner side of the outer lip, the presence of three folds columellar callus absent. excavated of the and the prominent parietal denticle; on the lower, portion columella, low at Parietal callus in adult forms narrow, ridge poste- presence of a strong parietal ridge and a raised parietal rior end of aperture; aperture ovate, its height/width ratio callus at the posterior end of the aperture set fasciole low, rounded. Umbilicus 2:3; siphonal very Austriumphis apart from other genera. Fusus absent. from the (Angistoma) labratulus von Koenen, 1889, Stratigraphic and geographic distribution — Early latest Eocene (Latdorfian) of northern Germany, Pliocene, South Africa. superficially resembles Austriumphis by lacking axial — the Included species Only type species, Triumphis ornament, but the German species differs in lacking the dilemma Kilburn & Tankard, 1975. parietal ridge, in having five denticles instead of Material examined — South African Museum PQAV fourteen lirae on the inner side of the outer lip, by and 945 (9 specimens), Hondeklip. lacking a determinate outer lip, by having a higher Discussion — I the for Other latest Eocene propose new genus an enigmatic spire (see von Koenen, 1889). to Pliocene buccinid that Kilburn & Tankard (1975) named Oligocene European species assigned to Angistoma Triumphis dilemma. The original material came from Sandberger, 1861 (type species Fusus ringens Beyrich, Pliocene the of characterised the of axial deposits at Langebaanweg, on west coast 1856) are by presence South Africa. & Pether Cape Province, Kensley (1986) ornament and by a narrowly elongate aperture (see have since reported this species from a comparable Janssen, 1979; Schnetler & Beyer, 1987, 1990). 49 Kensley, & J. Pether, 1986. Late Tertiary and Early Quater- Austriumphis may belong to the subfamily Photinae, B., the with such other Cominella 1850, nary fossil Mollusca of Hondeklip area, Cape Province, along genera as Gray, South Africa. — Annals of the South African Museum, 97: and Afrocominella Iredale, 1918. It differs from most 141-225. Photinae by the complete absence of axial ornament. A Kilburn, R.N., & A.J. Tankard, 1975. Pleistocene molluscs more definitive assignment must await a thorough from the west and south coasts of the Cape Province, South review of the entire complex of genera now assigned to Africa. — Annals of the South African Museum, 67: 183- the Buccinidae. 226. As I understand the is group, Austriumphis an A. 1889. Das Norddeutsche und Koenen, von, Unter-Oligocan extinct, monotypic genus confined to the Pliocene of seine Mollusken-Fauna. Lieferung I: Strombidae- der South Africa. with other in the — Along many species Muricidae-Buccinidae. Abhandlungen zu geolo- Preussen und den deposits at Langebaanweg and Hondeklip Bay, A. gischen Spezialkarte von Thiiringischen 10: 280 Staaten, pp. dilemma probably lived in shallow water, and may have Schnetler, K.I., & C. Beyer, 1987. A Late Oligocene (Chattian been a common constituent of low intertidal or shallow B) mollusc fauna from the clay-pit of Galten Brickworks at sublittoral rocky-bottom communities. Nprre Vissing, Jylland, Denmark. — Mededelingen van de Tertiaire Kwartaire 193- Werkgroep voor en Geologie, 24: 224. ACKNOWLEDGEMENTS Schnetler, K.I., & C. Beyer, 1990. A Late Oligocene (Chattian B) molluscan fauna from the coastal cliff at Mogenstrup, I thank J. Pether for the loan of specimens, and the north of Skive, Jutland, Denmarks. — Contributions to National Science Foundation (NSF EAR-94-05547) for Tertiary and Quaternary Geology, 27: 39-81. Vermeij, G.J., & P.W. Signor, 1992. The geographic, financial support of the project of which this paper forms taxonomic and distribution of determinate growth small temporal a part. in marine gastropods. — Biological Journal of the Linnean Society (London), 47: 233-247. REFERENCES Janssen, R., 1979. Die Moilusken des Oberoligozans (Chattium) im Nordseebecken. 2. Neogastropoda, Euthyneura, Cephalopoda. — Archiv fur Molluskenkunde, 109: 277-376. Manuscript received and accepted 22 July 1996..
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