Cretaceous Faunas from Zululand and Natal, South Africa. The

Cretaceous faunas from Zululand and Natal, South Africa. The desmoceratoid ammonite genera Moretella Collignon, 1963, Beudanticeras Hitzel, 1902, and Aioloceras Whitehouse, 1926 William James Kennedy Oxford University Museum of Natural History, Parks Road, Oxford OX1 3PR, U.K., and Department of Earth Sciences, South Parks Road, Oxford OX1 3AN, U.K. E-mail:[email protected] & Herbert Christian Klinger Natural History Collections Department, Iziko South African Museum, P.O. Box 61, Cape Town, 8000 South Africa E-mail: [email protected] (with 14 figures) Received 19 June 2012. Accepted 10 August 2012 Three taxa of desmoceratoid ammonites are recognized in the Lower Albian of northern KwaZulu-Natal, all of them previously known only from Madagascar: Moretella sp., Beudanticeras komihevitraense Collignon, 1950, and Aioloceras besairiei (Collignon, 1949). Madagascan type and figured material, much of it difficult to interpret from the original figures is re-illustrated, and the intraspecific variation and dimorphism in Moretella and Aioloceras are documented. Key words: ammonites, Desmoceratoidea, Albian, Cretaceous, KwaZulu-Natal, Madagascar. CONTENTS Abstract · · · · · · · · · · · · · · · · · · 55 Family · · · · · · · 56 Genus Aioloceras · · · · · · · · · · 58 Introduction · · · · · · · · · · · · · · · 55 Genus Moretella · · · · · · · · · · · · · 56 Aioloceras besairiei · · · · · · · · 58 Repositories of specimens · · 55 Moretella sp. · · · · · · · · · · · · · · · · 56 Acknowledgements · · · · · · · · 61 Field localities · · · · · · · · · · · · · 55 References· · · · · · · · · · · · · · · · 61 Conventions · · · · · · · · · · · · · · 56 Genus Beudanticeras· · · · · · · · · 57 Figures 1–14 · · · · · · · · · · · · · · 62 Systematic palaeontology · · · 56 Beudanticeras komihevitraense · 57 INTRODUCTION Bourgogne, Dijon. Accordingly, we re-illustrate here key Desmoceratoid ammonites from the Lower Albian part of type and figured specimens relevant to the interpretation of the Mzinene Formation of northern KwaZulu-Natal were the KwaZulu material. recorded as species of ‘Beudanticeras’ and ‘Cleoniceras’ from division Albian II in our preliminary account of the REPOSITORIES OF SPECIMENS ammonite faunas of the region (Kennedy & Klinger, 1975, EMP: École National Supérieur des Mines, Paris, now p. 276)). We subsequently recognized Aioloceras as a key housed in the Université de Lyon-Villeurbanne. element of a Tegoceras mosense/Aioloceras fauna (Kennedy OUM: Geological Collections, Oxford University Museum & Klinger, 2008, p. 79). Study of the classic Lower Albian of Natural History, Oxford. faunas of Madagascar (Collignon, 1949, 1950, 1963) has SAM: Natural History Collections Department, Iziko enabled us to recognize three taxa in KwaZulu-Natal, South African Museum, Cape Town. Moretella sp., Beudanticeras komihevitraense Collignon, UB: Département des Sciences de la Terre, Université 1950, and Aioloceras besairiei (Collignon, 1949). The quality de Bourgogne, Dijon. of reproduction of the plates in the Albian volume (1963) of Collignon’s Atlas des fossiles caractéristiques de Madagascar FIELD LOCALITIES (Ammonites) did not do justice to the specimens, or the Details of field localities are given by Kennedy & Klinger original photographs, and many taxa are difficult if not (1975); further descriptions of these localities are deposited impossible to interpret without an examination of the actual in the Geological Collections, Oxford University Museum of specimens, housed in the collections of the Université de Natural History, The Natural History Museum, London, ZooBank: urn:lsid:zoobank.org:pub:A78B034A-B70D-455E-8CEE-806A3A08223E (http://www.zoobank.org) Published on the 12th of December 2012 at Sabinet, Pretoria (http://reference.sabinet.co.za/sa_epublication/afnathist) 56 African Natural History, Volume 8, December 2012 and the Natural History Collections Department, Iziko Moretella transiens (Collignon, 1949): Collignon, 1949, South African Museum, Cape Town. Specimens with pre- p. 74, pl. 13, fig. 10; 1963, p. 101, pl. 281, fig. 1212 fixes EM or LJE were presumably collected from the Albian (Fig. 1J–L). localities on the western side of the Pongola River, north of Moretella undata Collignon, 1963, p. 103, pl. 281, fig. 1220 the Mfongozi Spruit, described by Haughton (1936, pp. (Fig. 2E–G). 290–292, fig. 3), (see Kennedy & Klinger 2011, fig. 24) The co-occurrence of seven species of Moretella within the Zone of Lemuroceras spathi and Brancoceras besairiei in CONVENTIONS Madagascar is unlikely. Where Collignon saw differences, Dimensions are given in millimetres: D = diameter; Wb = we see dimorphism and intraspecific variation: the morpho- whorl breadth; Wh = whorl height; U = umbilicus; c = costal logical differences between his species are trivial. Already in dimension; ic = intercostal dimension. Figures in brackets 1949 Collignon regarded moreti (Figs 1Q–S, 2K–L) as a are dimensions as a percentage of the diameter. The suture passage form between ambigua (Figs1A’,B’, 2C,D) and terminology is that of Korn et al. (2003): E = external lobe; madagascariensis (Fig. 1A–F) and we regard them as A = adventive lobe (= lateral lobe, L, of Kullmann & synonyms. It is likely that further analysis of the assemblage Wiedmann 1970); U = umbilical lobe; I = internal lobe. will lead to the conclusion that most of his species are synonyms. SYSTEMATIC PALAEONTOLOGY We are unable to see any significant differences between several of the ‘Pseudosonneratia’ not included in Moretella Superfamily DESMOCERATOIDEA Zittel, 1895 by Collignon, in particular dondeyi Collignon, 1963, p. 105, Family CLEONICERATIDAE Whitehouse, 1926 pl. 282, fig. 1230, and ihopensis Collignon, 1963, p. 106, (= Vnigriceratinae Saveliev, 1973; Lemuroceratinae Owen, 1988) pl. 282, fig. 1231 (Fig. 2P,Q), which we include in Moretella here. Genus Moretella Collignon, 1963 Collignon suggested that the origin of Moretella lay in Lemuroceras Spath, 1942. The resemblance between a Type species specimen referred to Moretella dubia by Collignon (Fig. 1Y), Pseudosonneratia madagascariensis Collignon, 1949, and the much larger (47 mm diameter), but still septate p. 81, pl. 16, figs 13, 14, by the original designation of holotype of Lemuroceras saintoursi Collignon, 1963 Collignon, 1963, p. 101. (Fig. 1W,X) is striking; they may even be dimorphs. A full revision of the numerous co-occuring Lemuroceras, Moretella Diagnosis aud ‘Pseudosonneratia’ from the Lower Albian of Madagascar Small, mature adults, presumed to be microconchs, are as is required to resolve their actual relationships. little as 40 mm in diameter. Coiling moderately evolute, with around 50% of the previous whorl covered. Whorl section Occurrence rounded, oval or subquadrate. Coarse primary ribs, bullate Lower Albian of Madagascar and northern KwaZulu-Natal. or not, arise at the umbilical seam and strengthen across the umbilical wall and shoulder. On the flanks ribs arise in pairs Moretella sp. at the shoulder or on the innermost flank, and are prorsi- Fig. 2R–T radiate and feebly flexuous; additional short ribs intercalate. All ribs strengthen on the ventrolateral shoulders and Material venter, which they cross in a shallow convexity. Suture SAM-PCZ22239, from the Lower Albian Mzinene Forma- moderately incised, with bifid E/A and A/U2 tion in the environs of locality 153 of Kennedy & Klinger (1975) on the side of the road leading up to Mantuma Rest Discussion Camp in the Mkuze Game Reserve, northern KwaZulu-Natal. Collignon (1963) referred the following species to his new genus Moretella: Dimensions Moretella ambigua (Collignon, 1949): p. 79, pl. 16, figs 1–4; 1963, p. 102, pl. 281, fig. 1216 (Figs 1A’,B’, 2C,D). D Wb Wh Wb: U Moretella balmensiformis (Collignon, 1949): Collignon, Wh 1949, p. 80, pl. 16, figs 5–8; 1963, p. 102, pl. 281, fig. 1215 SAM-PCZ22239 48.0 (100) 20.0 (41.7) 20.9 (43.5) 0.96 14.9 (31.0) (Fig. 1G–I, P, Z). Moretella dubia (Collignon, 1949): Collignon, 1949, p. 74, Description pl. 15, fig. 2; 1963, p. 102, pl. 281, fig. 1213 (Fig. 1M–O). The specimen is wholly septate, and retains recrystallized Moretella madagascariensis (Collignon, 1949): Collignon, shell. Coiling is moderately evolute, with 50% of the previous 1949, p. 81, pl. 16, figs 13, 14; 1963, p. 102, pl. 281, fig. 1217 whorl covered. The umbilicus comprises 31% of the diameter, (Fig. 1A–F). and is of moderate depth, with a convex wall and broadly Moretella moreti (Collignon, 1949): Collignon, 1949, p. 75, rounded umbilical shoulder that merges imperceptibly with pl. 15, fig. 4; 1963, p. 102, pl. 281, fig. 1214 (Fig. 1Q–S). the feebly convex, subparallel flanks. The ventrolateral Moretella subquadrata Collignon, 1963, p. 103, pl. 281, shoulders are broadly rounded, the venter relatively broad, figs 1218, 1219 (Fig. 2H–J, M–O). and feebly convex. There are 25–26 ribs on the outer whorl. Kennedy & Klinger: The desmoceratoid ammonite genera Moretella, Beudanticeras and Aioloceras 57 Twelve primaries arise at the umbilical seam, and Natal. OUM KX 11070–11072, 11074–11076, are from the strengthen into strong bullae, perched on the umbilical Lower Albian Mzinene Formation at locality 36 of Kennedy shoulder. These give rise to pairs of strong, feebly flexuous & Klinger (1975), degraded cliffs on the eastern bank of the coarse ribs, feebly convex on the inner to middle flank and Mzinene close to the boundary between lots H 84 14107 and feebly concave on the outer flank, sweeping forwards, coars- H 85 14108, 27°57’14”S, 32°18’34”E, northern

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