New and little-known Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar

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1 New and little-known Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar Herbert Christian Klinger Natural History Collections Department, Iziko South African Museum, P.O. Box 61, Cape Town, 8000 South Africa . William James Kennedy Geological Collections, Oxford University Museum of Natural History, Parks Road, Oxford, OX1 3PW, U.K. . & Wolfgang Erich Grulke P.O. Box , Benmore, 2010 South Africa . (with 18 figures) Submitted 27 June Accepted 22 August 2007 Examination of the Madagascan material in the collection of the late General M. Collignon, currently housed in the Centre des Sciences de la Terre, Université de Bourgogne, Dijon, and specimens in the private collection of W.E. Grulke, allow us to comment on, or add to, the descriptions of little-known species from that region, as well as to describe several new taxa belonging to the heteromorph ammonite families Nostoceratidae Hyatt, 1894 and Diplomoceratidae Spath, For comparison, some specimens from KwaZulu-Natal, South Africa are included. The following are described: Nostoceras malagasyense (Collignon, 1971), Nostoceras collignoni sp. nov., Anaklinoceras sp. aff. budayi Foldyna & Vasícek, 1977, Jouaniceras? sp., Madagascarites andimakensis Collignon, 1966, Eubostrychoceras indopacificum Matsumoto, 1967, Amapondella amapondense (van Hoepen, 1921), Ankinatsytes yabei Collignon, 1965, Eodidymoceras enigma sp. nov., Pseudoxybeloceras? stoliczkai sp. nov., Pseudoxybeloceras sp., Schlueterella compressum Klinger, 1976, Schlueterella sp. aff. S. pseudoarmatum (Schlüter, 1872), Schlueterella sp. aff. S. tenuiannulatum Collignon, In addition, dimorphism is demonstrated in Amapondella amapondense. Key words: Ammonites, Nostoceratidae, Diplomoceratidae, Madagascar. Abstract 89 Location of specimens 89 Field localities and stratigraphic terminology 89 Dimensions and terminology 90 Systematic palaeontology 90 Nostoceras malagasyense 90 Nostoceras collignoni 91 CONTENTS Anaklinoceras sp. aff. A. budayi 94 Jouaniceras? sp. 94 Madagascarites andimakensis 97 Eubostrychoceras indopacificum 97 Amapondella amapondense 101 Ankinatsytes yabei 102 Eodidymoceras enigma 102 Pseudoxybeloceras? stoliczkai 109 Pseudoxybeloceras sp 109 Schlueterella compressum 109 Schlueterella sp. aff. S. pseudoarmatum 111 Schlueterella sp. aff. S. tenuiannulatum 113 Acknowledgements 113 References 113 LOCATION OF SPECIMENS The following abbreviations are used to indicate the depositories of specimens mentioned in the text: UBGD UFR des Sciences de la Terre, Université de Bourgogne, Dijon. SAM Natural History Collections Department, Iziko, South African Museum, Cape Town. SAS Council for Geosciences (formerly Geological Survey of South Africa), Pretoria. WGC Wolfgang Erich Grulke Collection, Morningside. FIELD LOCALITIES AND STRATIGRAPHIC TERMINOLOGY Details of Collignon s Madagascan field localities are taken from his series Atlas des fossiles caractéristiques de Madagascar (Ammonites), volumes XIII XVII (Collignon 1965, 1966, 1969, 1970, 1971). We retain his term of Gisement for these localities. Details of South African localities are given by Kennedy & Klinger (1975). The biostratigraphic terminology used here is that compiled by Collignon ( ) and Besairie &

2 90 African Natural History, Volume 3, 2007 Collignon (1972) in full cognizance that it is applicable only to Madagascar and that it is, in part, incorrect and not synchronous with the standard Cretaceous stage boundaries (see e.g. Kennedy & Klinger 1975; Klinger & Kennedy 1984; Walaszczyk et al and Kennedy et al., in press). DIMENSIONS AND TERMINOLOGY Dimensions are given in millimetres. Wb = whorl breadth; Wh = whorl height; Wb:Wh = ratio of whorl breadth to whorl height. Rib index is ribs counted along the length of the specimen over a distance equal to the whorl height measured at the middle of that distance. The terms adapical and abapical refer to the upper and lower sides respectively of the whorls of the helix with the apex of the latter pointing dorsally. SYSTEMATIC PALAEONTOLOGY Pending a revision of the taxonomy of the families Nostoceratidae and Diplomoceratidae we use nomenclature that is based partially on that of Wright (1957b, 1997) (see also Klinger & Kennedy 2003). Until we have clarity on the interrelationship of the various taxa, we refrain from the use of subgeneric names in the current descriptions. Suborder ANCYLOCERATINA Wiedmann, 1966 Superfamily TURRILITOIDEA Gill, 1871 Family NOSTOCERATIDAE Hyatt, 1894 (= Jouaniceratidae Wright, 1952; Bostrychoceratinae Spath, 1953; Hyphantoceratinae Spath, 1953; Emperoceratinae Spath, 1953; Proavitoceratinae Spath, 1953 errore pro Pravitoceratinae) Genus Nostoceras Hyatt, 1894 Type species Nostoceras stantoni retrorsum Hyatt, 1894, by original designation of Hyatt (1894: 569). Nostoceras malagasyense (Collignon, 1971) Figs 1 2, 4C, 5D F 1971 Emperoceras malagasyense Collignon, p. 5, pl. 642 (figs ). Type Holotype is UBGD 12367, the specimen figured by Collignon (1971, pl. 642 (fig. 2367)); paratypes are UBGD (pl. 642 (figs )) all from the lower Maastrichtian Zone of Pachydiscus gollevillensis and Pachydiscus neubergicus at Gisement 496-B, Ianjona- Ouest-Mikoboka (Manera). Material WGC1333 from Belo sur Tsiribihina, and UBGD , both from the same locality as the holotype and paratype. Description A single concretion of greenish glauconitic matrix contains seven, all nearly complete nostoceratid specimens in aragonitic shelly preservation. None of the specimens has the very early ontogenetic stages preserved, but there are no indications of irregular Didymoceras-like coiling. The helix is low, with a wide apical angle of about 110 degrees. Coiling is both dextral and sinistral. The whorl section is initially depressed, wider than high, but eventually becomes distinctly compressed-ovoid, higher than wide on the last helical whorl. Ornament consists of thin, thread-like ribs bearing two rows of tubercles in irregular fashion. The adapical row of tubercles is situated slightly above the umbilical suture, whereas the abapical row is near the base of the flanks. The tubercles are small, and in cases hardly wider than the ribs. They are arranged in irregular fashion; some on single, some on looped ribs and others on alternate or bifurcating ribs. The presence and strength of tubercles is extremely variable. In the holotype they are absent, in the paratype poorly developed, and in the specimen in Fig. 1 at the top of the concretion, distinct. The body chamber is suspended obliquely below the base of the spire and ends in a simple collared aperture at a distance nearly equal to that of the height of the last helical whorl. Ribbing on the last part of the recurved crozier becomes regular, with ventrolateral tubercles on each rib. Discussion The matrix and the shelly preservation of the large concretion is quite unlike that of the Maastrichtian material described by Collignon (1971) and examined by Kennedy and Klinger respectively in the collections at Dijon and here illustrated in Fig. 5 D F. This species was originally described by Collignon (1971: 5, pl. 642 (figs )) as Emperoceras malagasyense. Emperoceras Hyatt, 1894 (type species: E. beecheri Hyatt, 1894) is generally regarded as a synonym of Didymoceras Hyatt, 1894; a genus characterized by an irregular early ontogentic stage and with later whorls loose or just touching (cf. Wright 1997: L247). Only one specimen (Fig. 1 bottom and Fig. 4C) shows a slight irregularity of the coiling of the early whorl, but we suspect that this may in part be due to fracture. Apart from this, the present material clearly shows that the general shell shape and ornamentation is typically that of the genus Nostoceras. Henderson et al. (1992: 136) considered Emperoceras malagasyense closely similar to, and probably conspecific with, N. (N.) attenuatum Brunnschweiler (1966: 40, pl. 8 (figs 8 10)), text-figs 25 26; see also Henderson et al. (1992: 134, figs 1, 2a c, 4d)). One specimen figured by Henderson et al. (fig. 1f g) is identical to the paratype UBGD 12368, but the holotype and another specimen figured by Henderson et al. (fig. 2a c) are much more finely ribbed than the Madagascan material. So, even though there seems to be some overlap in morphologies between the Australian and Madagascan specimens, it seems reasonable to retain N. attenuatum and N. malagasyense separate. The specimen described by Collignon (1971: 12, pl. 644 (fig. 2383)) as Nostoceras stantoni serratum may merely represent the early whorls of this species, but it is too poorly preserved for definite comment. Alternatively, it may represent the early whorls of Bostrychoceras sanctaeluciense (Klinger, 1976) as suggested by Klinger (1976: 67) and Klinger & Kennedy (2003: 259). Occurrence Lower Maastrichtian, Madagascar.

3 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 91 Fig. 1. Nostoceras malagasyense (Collignon, 1971). WGC 1333 from the Maastrichtian of Belo sur Tsiribihina, Madagascar. 1. Nostoceras collignoni sp. nov. Figs 3 4A, 5G I, 12A 1971 Nostoceras hyatti Steph.; Collignon, p. 5, pl. 642 (fig. 2366); p. 8, pl. 643 (fig. 2371) Nostoceras cf. hyatti Steph.; Collignon, p. 8, pl. 643 (fig. 2372). Type Holotype is UBGD 12366, the specimen figured by Collignon (1971: 5, pl. 643 (fig. 2366)) from the lower Maastrichtian, Zone of Pachydiscus gollevillensis and Pachydiscus neubergicus at Gisement 496-B, Ianjona Ouest-Mikoboka (Manera).

4 92 African Natural History, Volume 3, 2007 Fig. 2. Nostoceras malagasyense (Collignon, 1971). WGC 1333 the same specimen as in Fig. 1, from the Maastrichtian of Belo sur Tsiribihina, Madagascar. 0.9 Material WGC1319. One nearly complete specimen plus part of another consisting of a section of the helix and recurved crozier from Belo sur Tsiribihina; UBGD both from the same locality as the holotype. Description Only two whorls of the helix are preserved in the more complete specimen in WGC1319. The apical angle is approximately 80 degrees. Ornament consists of low, widely-spaced ribs. Two rows of tubercles, ca. 16 per whorl, are situated on pairs of ribs; one above mid-flank and the other at the abapical edge. A single rib normally separates the looped tuberculate ones. The upper, adapical row of tubercles may be slightly stronger than the lower. Ornament becomes conspicuously coarse on the recurved body chamber, con-

5 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 93 Fig. 3. Nostoceras collignoni sp. nov. WGC 1319 from the Maastrichtian of Belo sur Tsiribihina, Madagascar. 1.

6 94 African Natural History, Volume 3, 2007 sisting of sharp, widely spaced ribs each bearing a pair of ventrolateral tubercles. Discussion The Madagascan material is similar to N. hyatti, but ornament both on the helix and on the body chamber is much coarser than on any known specimens of the latter species. The specimen recorded by Sornay (1951: 274, pl. 4 (figs 1 3)) as N. angolense has comparable ornament on the crozier, but is based on insufficient material for further comparisons. Occurrence Lower Maastrichtian, Madagascar. Genus Anaklinoceras Stephenson, 1941 Type species Anaklinoceras reflexum Stephenson, 1941 by original designation (Stephenson 1941: 414). Anaklinoceras sp. aff. A. budayi Foldyna & Vasícek, 1977 Fig. 4B Compare: 1977 Anaklinoceras budayi Foldyna & Vasícek 1977, p. 122, pl. 4 (figs 1 2) Anaklinoceras kersianum Foldyna & Vasícek 1977, p. 124, pl. 3 (fig. 2) Anaklinoceras cf. budayi n. sp. Foldyna & Vasícek 1977, pl. 4 (fig. 3) Nostoceras (Nostoceras)? budanyi (sic) (Foldyna & Vasícek); Kennedy p. 467, figs 4.4, , 4.11; , , Material WGC 1408 said to be from Toliara, Betioky, southern Madagascar. Description The single, complete, minute specimen consists of a helix, an upward curving shaft and recurved crozier. The helix consists of four whorls, with an acute apical angle of about 60 degrees. Ornament consists of fine, single ribs, each bearing two rows of tubercles. At the base of the helix the shell curves upwards, at an angle with the axis of the former, forming a straight shaft that extends nearly twice the height of the spire, before forming a recurved crozier, with the aperture situated a small distance away from the apex of the helix. Ribbing on the shaft and crozier is coarser than on the helix, but is bituberculate throughout. Discussion Even though the present record is based on a single specimen lacking precise stratigraphic data, the atypical coiling and the first occurrence of the genus from Madagascar merit description. Anaklinoceras differs from Nostoceras in that the body chamber coils upwards, and around the apex of the helix instead of being suspended below the helix. In typical Anaklinoceras, A. reflexum Stephenson, 1941 (see restoration in Cobban et al. 1992, fig. 5), the body chamber curves upwards, along the side of the helix, and recurves over the apex of the helix. There is, however, much variation in the mode of the uncoiled section. In some, A. incertum Kennedy et al. (2000: 233, pl. 12 (figs 1 13); pl. 13 (figs 7 9); textfigs 8 9), the uncoiled section is C-shaped, and not in contact with the sides of the helix and the aperture does not extend over the helix. In A. gordiale Cobban et al. (1992: A6, pl. 1 (figs 18 22); text-fig. 6), the body chamber coils around the helix in a planispiral manner, mimicking the Barremian genus Colchidites Djanélidzé, 1926 or the Santonian Jouaniceras Basse, The only nostoceratid taxa with which the present specimen may be compared were described by Foldyna & Vasícek as Anaklinoceras budayi (1977: 122, pl. 4 (figs 1 2)), Anaklinoceras kersianum (1977: 124, pl. 3 (fig. 2)) and Anaklinoceras cf. budayi (pl. 4 (fig. 3)) from the uppermost Campanian of NW Iraq. These were all treated as synonyms of N.? budanyi (sic) by Kennedy (2000: 467, figs 4.4, , 4.11; , , 5.11). While we agree with Kennedy that budayi and kersianum are probably synonyms, we follow Foldyna & Vasícek in referring them to Anaklinoceras rather than to Nostoceras. Our specimen is closest to the holotype of A. kersianum figured by Foldyna & Vasícek (1977, pl. 3 (fig. 2)). All the other specimens referred to A. budayi by Foldyna & Vasícek (1977) and Kennedy (2000) seem to have a longer shaft and crozier and sparser ribbing. For the present we refer to the specimen as Anaklinoceras sp. aff. A. budayi. Occurrence Upper Campanian?, Madagascar. Genus Jouaniceras Basse, 1939 Type species Lytoceras Sicardi De Grossouvre,1894 by original designation (Basse 1939: 43). Jouaniceras? sp. Fig. 5J L Compare: 1894 Lytoceras Sicardi De Grossouvre, p. 223, pl. 37 (figs 6, 11) Lytoceras (Jouaniceras) Sicardi De Grossouvre; Basse p. 43, pl. 3 (figs 3 7), p. 42, text-fig Jouaniceras sicardi (De Grossouvre); Kennedy, p. 429, pl. 28 (figs 1 8, 10 19); text-fig. 35. Material UBGD from the upper Santonian, Zone of Pseudoschloenbachia umbulazi, at Gisement 283, Coupe Ampolipoly-Antsira-Behamotra (Belo sur Tsiribihina). Description A body chamber fragment consisting of less than a third of a whorl with prominent flared ribs, separated by one to three thinner, wiry ribs is tentatively referred to this genus. On the inside of the whorl distinct impressions of the flared ribs of the previous whorl are clearly visible. Discussion Despite the fact that we have less than a third of a body chamber whorl available, the distinctive ornament of flared and subsidiary ribs, associated with the clear impressions on

7 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 95 Fig. 4. A, Nostoceras collignoni sp. nov. WGC 1319 from the Maastrichtian of Belo sur Tsiribihina, Madagascar. 1. B, Anaklinoceras sp. aff. A. budayi Foldyna & Vasícek, WGC 1408 from the Campanian? of Madagascar C, Nostoceras malagasyense (Collignon, 1971). Specimen with slightly irregular early whorl (due to fracture?) (see Fig. 1 lower specimen). 2.25

8 96 African Natural History, Volume 3, 2007 Fig. 5. UBGD A C, Amapondella amapondense? (van Hoepen, 1921) from the lower Campanian at Gisement 202. D F, Nostoceras malagasyense (Collignon, 1971). D, UBGD , E F, UBGD , both from the lower Maastrichtian, Zone of Pachydiscus gollevillensis and Pachydiscus neubergicus at Gisement 496-B, Ianjona-Ouest-Mikoboka (Manera). G I, Nostoceras collignoni sp. nov. G, UBGD , H I, UBGD , both from the same locality as A C. J L, Jouaniceras? sp. UBGD from the upper Santonian Zone of Pseudoschloenbachia umbulazi at Gisement 283, Coupe Ampolipoly-Antsira-Behamotra (Belo sur Tsiribihina). All 1.

9 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 97 the dorsum of the flared ribs of the previous planispiral whorl suggest that this may be a representative of the genus Jouaniceras. However, all known specimens of Jouaniceras are significantly smaller, and for the present we prefer to refer the specimen to that genus with a question mark.the only other species of similar age with which the specimen could possibly be confused is Amapondella amapondense (van Hoepen, 1921). That species, however, lacks the impressions of the preceding, helical stage. Even if it were a more tightly coiled body chamber of A. amapondense, the impressions of the ribs of the helix would be parallel to the length of the specimen, rather than at right angles. Occurrence Jouaniceras sicardi is known only from the middle and upper Santonian gallicus and paraplanum subzones in the Corbières, France, and the middle Santonian of northern Spain. If our tentative identification proves to be correct, this would be the first first record of the genus Jouaniceras from Madagascar. Genus Madagascarites Collignon, 1966 Type species Madagascarites andimakensis Collignon, 1966 by original designation (Collignon 1966: 26) Madagascarites andimakensis Collignon, 1966 Figs 6 8, 9A B 1966 Madagascarites andimakensis Collignon, p. 26, pl. 465 (figs ) Hyphantoceras ingens Collignon, p. 24, pl. 464 (fig. 1896) Madagascarites andimakensis Collignon; Klinger & Kennedy, p. 78, fig. 5f Madagascarites andimakensis Collignon; Klinger & Kennedy, figs 1 6a. Type Holotype is the specimen figured by Collignon (1966, pl. 465 (fig. 1897)), UBGD11897 refigured by Klinger & Kennedy (1997, figs 1 4) and here, Fig. 6A, from the middle Santonian, Zone of Texanites hourcqi at Gisement 734, Sud Ambiky (Belo sur Tsiribihina), Madagascar. The holotype was photographed by Klinger in 1973 when the collection was still at General Collignon s house in Moirans, but it could not be located in the Collignon type and figured collection in Dijon in 1999, and must be presumed lost. Material A photograph of the holotype, the holotype of Hyphantoceras ingens Collignon, UBGD a synonym of M. andimakensis, UBGD , SAM-GMC 733, ex Collignon Collection both from the middle Santonian, Zone of Texanites hourcqi at Gisement 733, Coupe d Ambikity, Andimaka (Belo sur Tsiribihina), UBGD276278, the specimen figured by Klinger & Kennedy (1997, figs 5a b, 6a) from the same substage and zone at Gisement 757, km 8500 Coupe S. Beantaly, Souromaraino (Belo sur Tsiribihina), UBGD from the same substage and zone at Gisement 754, Coupe Andimaka-Souromaraino (Belo sur Tsiribihina), UBGD from the upper Santonian, Zone of Pseudoschloenbachia umbulazi at Gisement 530, Ambararata-Mikoboka (Manera) and UBGD from the same substage and zone at Gisement 688, Coupe Ampamba-Antsirasira (Belo sur Tsiribihina). Description and discussion The species was discussed extensively by Klinger & Kennedy (1997), and the present material further confirms our conclusions. The first concerns the alleged irregular Nipponites-like coiling of the early whorls of the holotype. This is incorrect as shown by Figs 6B and 7E. The early whorls are coiled in an open helix, followed by a body chamber that curves upwards, and partially over the top of the helix. The ornament of M. andimakensis consists of looped ribs, bearing four rows of tubercles, separated by a variable number of single, non-tuberculate ribs. On the body chamber the tuberculate ribs may lose their looped form and become either thickened or single, but this is quite variable. Hyphantoceras ingens has the same general ornament of M. andimakensis, and is regarded as a synonym, albeit a much larger form of the latter. The total variation in size is illustrated by UBGD (Fig. 6B C), the smallest, through the holotype, (Fig. 6A) to H. ingens (Fig. 8). Klinger & Kennedy (1997: 233) initially ascribed the variation in size to dimorphism, but we suspect that the differences in size may in part also possibly reflect intraspecific variation or merely different rates of reaching maturity. Occurrence Middle and upper Santonian of Madagascar, and subsurface Santonian of Richards Bay, KwaZulu, South Africa. Genus Eubostrychoceras Matsumoto, 1967 Type species Eubostrychoceras indopacificum Matsumoto, 1967 by original designation (Matsumoto 1967: 332). Eubostrychoceras indopacificum Matsumoto, 1967 Fig. 10A H 1967 Eubostrychoceras indopacificum Matsumoto, p. 333, pl. 18 (fig. 1) Eubostrychoceras (Eubostrychoceras) indopacificum Matsumoto; Klinger & Kennedy, p. 225, fig. 1d g. (with synonymy) Type Holotype is GPIS (Tohoku University Collection), the specimen figured by Matsumoto (1967, pl. 18 (fig. 1)) from the Coniacian of Sakurazawa, Fukushima Prefecture, NW Japan. Discussion Eubostrychoceras indopacificum is a relatively welldefined species, known from the Coniacian of Hokkaido, Madagascar, KwaZulu, offshore Alphard Group of South Africa and possibly from the Coniacian of the Sergipe Basin in Brazil. It is here included, because the species, and specifically specimens from the Coniacian of Madagascar, help to clarify the alleged Coniacian and early Campanian

10 98 African Natural History, Volume 3, 2007 Fig. 6. Madagascarites andimakensis Collignon, A, The holotype, figured by Collignon (1966, pl. 465 (fig. 1897)), now presumed lost, from the middle Santonian Zone of Texanites hourcqi at Gisement 734, Sud Ambiky (Belo sur Tsiribihina, Madagascar). B C, UBGD , from Gisement 754. D E, UBGD from Gisement 688. All 1.

11 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 99 Fig. 7. Madagascarites andimakensis Collignon, A C, UBGD , from the upper Santonian, Zone of Pseudoschloenbachia umbulazi at Gisement 530. D, UBGD from the middle Santonian Zone of Texanites hourcqi at Gisement 733, Sud Ambiky (Belo sur Tsiribihina). E, UBGD from the middle Santonian, Zone of Texanites hourcqi at Gisement 757, km 8500 Coupe Sud Beantaly, Souromaraina (Belo sur Tsiribihina). F G, SAM-GMC 733, from the same horizon and zone at Gisement 733. All 1. records of Hyphantoceras reussianum (d Orbigny, 1850) from Madagascar, as well as its probable relationship with the Santonian/Campanian genus Amapondella Klinger & Kennedy, Collignon illustrated several specimens of Eubostrychoceras indopacificum (as Bostrychoceras indicum Stoliczka or B. aff. indicum) from the lower and middle Coniacian of Madagascar (Collignon 1965: 10, pl. 417 (fig. 1726); p. 12, pl. 419 (figs ) (see Figs 10A C, F here)). What is striking about these specimens is the presence of frequent constrictions, accompanied by a conspicuous flared rib. In some specimens, the flared ribs are very well developed, and restricted to the final portion of body chamber. Such were separated by Collignon as Bostrychoceras auriculatum

12 100 African Natural History, Volume 3, 2007 Fig. 8. Madagascarites andimakensis Collignon, UBGD 11896, The holotype of Hyphantoceras ingens Collignon (1966: 24, pl. 464 (fig. 1896)) from the middle Santonian, Zone of Texanites hourcqi at Gisement 230, Antsoha (Antsalova) Collignon (1965: 10, pl. 418 (fig. 1725)). Collignon also described Hyphantoceras reussi and Hyphantoceras cf. reussi from the lower and middle Coniacian, respectively (Collignon 1965: 14, pl. 419 (figs )) (here Fig. 10D E, G H)); the latter from the same locality (Gisement 344) as B. indicum (figs ). These alleged Coniacian records of H. reussianum are, in fact, merely specimens of E. indopacificum with more strongly developed flared ribs on the body chamber as in E. auriculatum. True H. reussianum is restricted to the Turonian, and best known from Europe, although recently (Walaszczyk et al. 2004: 551, fig. 10Ca Cc) it has also been recorded from Madagascar. Wright (1957a: 806, pl. 54 (fig. 2a b)) tentatively recorded H. reussianum from New Zealand. We believe that the Amapondella, type species Heteroceras amapondense van Hoepen, 1921 has its origins in these specimens of Eubostrychoceras with flared ribbing on the body chamber. We are aware, however, that transitional forms in the stratigraphic interval between the last occurrence of these flared Eubostrychoceras and the first Amapondella in the middle Santonian have not yet been found. Amapondella has simple ribbing on the early part of the helical phragmocone; flared, non-tuberculate ribs start appearing at variable stages on the helix, separated by a variable number of normal ribs. On the last part of the helix, and on the upwardly curved body chamber, these flared ribs may become extremely enlarged, and in some, with no intermediary ribs. Genus Amapondella Klinger & Kennedy, 1997 Type species Heteroceras amapondense van Hoepen, 1921 by original designation (Klinger & Kennedy 1997: 246).

13 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 101 Fig. 9. A B, Madagascarites andimakensis Collignon, UBGD from the middle Santonian, Zone of Texanites hourcqi at Gisement 757, km 8500 Coupe S. Beantaly, Souromaraina (Belo sur Tsiribihina). C, Schlueterella compressum Klinger, WGC 1289 from the Coniacian of Toliara, Betioky. All 1. Amapondella amapondense (van Hoepen, 1921) Figs 5A C, 10I J, 11, 12B I, 13A E, M 1921 Heteroceras amapondense van Hoepen, p. 17, pl. 4 (figs 1 2) Hyphantoceras reussianum d Orb.; Collignon, p. 29, pl. 523 (fig. 2064), p. 38, pl. 527 (figs ); p. 48, pl. 531 (fig. 2095) Anaklinoceras (?) stephensoni Collignon, p. 50, pl. 532 (fig. 2096) Eubostrychoceras (Amapondella) amapondense (van Hoepen); Klinger & Kennedy p. 235, figs 5 6, 7a, 8a d, 9a c (with synonymy) Type Holotype, by original designation, is the specimen figured by van Hoepen (1921, pl. 4 (figs 1 2)) from the upper Santonian or lower Campanian of the Mzamba Formation at the type section at locality 1, Eastern Cape Province. Material UBGD , from the lower Campanian, Zone of Karapadites karapadensis, Subzone of Maorites aemilii at Gisement 708, km 8,400 de la Coupe Ampamba-Antsirasira (Belo sur Tsiribihina), UBGD from the same zone and subzone at Gisement 166, de la Coupe de Berere I (Belo sur Tsiribihina), UBGD from the lower

14 102 African Natural History, Volume 3, 2007 Campanian, Zone of Karapadites karapadensis, Subzone of Scaphites reesidei at Gisement 190 de la Coupe de Berere II (Belo sur Tsiribihina) and lower Campanian, level of the base of the Neogauthiericeras zafimahovai Zone, at Gisement 202, Coupe de Berere II (Belo sur Tsiribihina). Description and discussion All of the specimens from the lower Campanian of Madagascar described by Collignon (see synonymy above) as Hyphantoceras reussianum are clearly portions of Amapondella amapondense with flared ribbing. The specimen figured by Collignon (1969, pl. 531 (fig. 2095)) is virtually identical to the body chamber of the specimen illustrated by Klinger & Kennedy (1997, fig. 13) and here Fig. 11. The specimen (UBGD ) here figured as Fig. 13A B is one with extremely strong, flared ribs without any intermediaries. The small specimen figured by Collignon (1969: 29, pl. 523 (fig. 2064)) is much smaller than any of the material of A. amapondense thus far known. In addition, it has loose, helical coils. Matsumoto (1977: 308) suggested that it may be a representative of the genus Ainoceras Matsumoto & Kanie, Comparison with UBGD (Fig. 12B H), both from Gisement 708, clearly shows that, apart from the loose helical coiling and smaller size, it has ornament identical to that of known specimens of A. amapondense, and is here interpreted as a microconch. This difference in size of micro- and macroconchs is comparable to that demonstrated by Kaplan & Schmid (1988, text-fig. 3) in H. reussianum, and is the first definite record of dimorphism in Amapondella. Some specimens of Scalarites, Scalarites venustum (Yabe, 1904)) (see Zonova & Yazykova 1998, pl. 8 (fig. 1)) resemble microconchs of A. amapondense in coiling and ornament, but the former is an older (Turonian) species. It does, however, indicate that the upward coiling of the body chamber towards or over the apex of the helix, is a common feature in several nostoceratid genera. Occurrence The species has a known range of middle Santonian to lower Campanian. In Pondoland (Eastern Cape Province) and in KwaZulu it occurs at or above the Santonian/ Campanian boundary. It is also found in offshore deposits of the Alphard Group which are probably derived from the Mzamba Formation (Klinger 1985); in Madagascar it occurs in the lower Campanian, from the base of the substage at the level of Neogauthiericeras zafimahovai to the Subzone of Maorites aemilii of the Zone of Karapadites karapadensis (see Table in Collignon 1969, p. 5); in Israel, Austria and Mississippi it occurs in the upper Santonian and in France, (Corbières) as low as the middle and lower upper Santonian, gallicus and paraplanum subzones. Genus Ankinatsytes Collignon, 1965 Type species Ankinatsytes yabei Collignon, 1965 by original designation (Collignon 1965: 16). Ankinatsytes yabei Collignon, 1965 Fig. 13 F L 1965 Ankinatsytes yabei Collignon, p. 16, pl. 420 (fig. 1738). Type Holotype, by monotypy, is UBGD 11738, the specimen figured by Collignon (1965, pl. 420 (fig. 1738)) from the lower Coniacian, Zone of Peroniceras dravidicum at Gisement 745-I, Coupe Ankinatsy-Souromaraino (Belo sur Tsiribihina). Material UBGD from the lower Coniacian at Gisement 167, Belo sur Tsiribihina, UBGD , from the middle Coniacian Zone of Kossmaticeras theobaldi and Barroisiceras onilahyense (lower level) at Gisement 334, Beantaly (Belo sur Tsiribihina). Description and discussion The present material does not add significantly to the description of the poorly preserved holotype of the species. The specimens confirm that coiling is in a low helix, and may possibly become straight on the body chamber. Ornament consists of flared ribs, bearing thee rows of pointed tubercles situated on the abapical part of the flanks, separated by non-tuberculate intermediaries. The affinities of Ankinatsytes yabei are obscure. It may be an atypical form of Hyphantoceras as implied by Wright (1997: L247), who included it in the synonymy of the latter genus, or even related to Allocrioceras as suggested by Collignon (1965: 16). Ankinatsytes venezolanus Renz (1982: 106, pl. 35 (fig. 1); text-fig. 81) is probably a representative of Allocrioceras. Occurrence Coniacian of Madagascar. Genus Eodidymoceras Klinger & Kennedy, 2003 Type species Nostoceras hyatti Stephenson var. mitraikyensis Collignon, 1970, by original designation (Klinger & Kennedy 2003: 291). Eodidymoceras enigma sp. nov. Figs Didymoceras subtuberculatum Howarth; Collignon, p. 42, pl. 529 (fig. 2086) Hyphantoceras (Madagascarites?) amapondense (van Hoepen); Klinger, p. 71 (pars), pl. 33 (fig. 2 only) Allocrioceras Cooper, p. 365, fig. 1f g Eubostrychoceras (Amapondella) amapondense (Van Hoepen); Klinger & Kennedy p. 245, fig. 15e only Allocrioceras sp.; Klinger & Kennedy, p. 246, fig Didymoceras (Eodidymoceras?) sp.; Klinger & Kennedy p. 300, fig. 8e, 52a d. Material UBGD , all from the lower Campanian, Zone of Anapachydiscus wittekindi and Eulophoceras jacobi, Subzone of Besairiella besairiei at Gisement 251 Coupe de Bevaho (Belo sur Tsiribihina), Madagascar and SAM-PCZ from locality 105, KwaZulu, St Lucia Formation, uppermost Santonian or basal Campanian.

15 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 103 Fig. 10. A C, F. Eubostrychoceras indopacificum Matsumoto, A, The original of Collignon (1966: 10, pl. 418 (fig. 1726)) Bostrychoceras indicum Stoliczka. B, The original of Collignon (1966: 12, pl. 419 (fig. 1727)) Bostrychoceras indicum Stol. C, The original of Collignon (1966: 12, pl. 419 (fig. 1728)) Bostrychoceras indicum Stol. F, The original of Collignon (1966: 12, pl. 419 (fig. 1729)) Bostrychoceras indicum Stol. D E, the original of Collignon (1966: 14, pl. 419 (fig. 1737)) Hyphantoceras cf. reussi d. Orb. G H, The original of Collignon (1966: 14, pl. 419 (fig. 1736)) Hyphantoceras reussi d Orb. I J, Amapondella amapondense (van Hoepen, 1921). UBGD , from the lower Campanian of Gisement 202, All 1. Type Holotype is UBGD (Fig. 14A C) from the lower Campanian of Gisement 251. Description The material consists mainly of fragments, and only two specimens, the holotype (Fig. 14A C) and paratype (Fig. 14F G) show more than one whorl. Coiling on the major part of the shell is in a low helix with a very wide apical angle. In the holotype (Fig. 14A C) the successive whorls are in contact with each other, and ornament of previous whorls is prominently impressed in the adapical parts of the succeeding whorls. In paratype UBGD (Fig. 14F G), an internal mould, the successive phragmocone whorls are apparently not in contact with each other. No complete post-helicoidal stage is known, but we suspect that the body chamber curves upwards and possibly partially over the helix (Figs 14D E, 15 I J). The earliest whorls are unknown, and may have simple ribbing, but on the greater part of the shell, ornament consists of prominent, flared ribs bearing two pointed rows of tubercles, separated by a variable number of non-tuberculate, simple ribs. On some internal moulds, e.g. paratype UBGD (Fig. 14F G) the flared ribs appear as low, rounded swellings. The position of the pointed tubercles on the flared ribs varies, from virtually ventrolateral and equidistant from midflank, to slightly asymmetrical with one row situated slightly above midflank and the other nearer to the abapical edge. Part of the

16 104 African Natural History, Volume 3, 2007 Fig. 11. Amapondella amapondense (Van Hoepen, 1921). A C, SAM-PCZ 7328, a macroconch from locality 105, KwaZulu, St Lucia Formation, upper Santonian/lower Campanian complex suture line and the midflank position of the siphuncle is shown in paratype UBGD (Fig. 14F G). Discussion Before examining the present material in the Collignon Collection, only fragments of the species were known to us, and we were unable to place the species in any genus with confidence. To complicate matters, the species is coeval with Amapondella amapondense. Both have flared ribs separated by thinner, non-flared ribs in later stages of growth. The only difference between the two species, especially when only fragments are available, is that the flared ribs in A. amapondense are entire, compared to bituberculate in E.enigma. On internal moulds, or worn fragments it is impossible to tell the species apart. This may explain why the species was initially included in A. amapondense (see Klinger 1976), referred to Allocrioceras by Cooper (1994) and only recently tentatively included in Eodidymoceras by Klinger & Kennedy (2003: 300, fig. 8e, 52a d). Initially, Klinger (1976: 71 72, pl. 33 (fig. 2)) included a latex cast of two specimens, one with distinct bituberculate flared ribs, and another with hamitid coiling and ornament in Hyphantoceras (Madagascarites?) amapondense. The former, as we now know, is clearly part of E. enigma; but the identity of the latter is still a mystery. We are not sure if it represents the early ontogeny of E. enigma or whether it is merely part of a co-occurring diplomoceratid genus; e.g. Glyptoxoceras. If it is part of E. enigma, the ontogenetic change in ornament of E. enigma and A. amapondense are identical, save for the bituberculate flared ribbing of the former species. Eodidymoceras enigma differs from all known species referred to the genus, e.g. E. mitraikyense (Collignon, 1970) (see Klinger & Kennedy 2003: 294, fig. 48) and E. howarthi Klinger & Kennedy (2003: 295, figs 49, 50a, 51) by the closer coiling and much wider apical angle. Didymoceras subtuberculatum Howarth (1965: 374, pl. 7 (figs 2 6); pl. 11 (fig. 4)) from the uppermost Campanian or basal Maastrichtian of Angola, to which species Collignon (1969: 42) had originally referred his only examined specimen, and which Klinger & Kennedy (2003: 298) tentatively referred to Eodidymoceras, has more prominent flared ribs separated by a greater number of intermediaries. The coiling also appears generally to be more loose in the form of a corkscrew, although this may be a variable feature. Occurrence In Madagascar the species is known only from the lower Campanian, but in the Eastern Cape and in KwaZulu it cannot be dated more precisely than uppermost Santonian/ basal Campanian where it co-occurs with A. amapondense.

17 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 105 Fig. 12. A, Nostoceras collignoni sp. nov. WGC 1319 from Belo sur Tsiribihina. B I, Amapondella amapondense (van Hoepen, 1921). B E, UBGD , F H, UBGD , from the lower Campanian, Zone of Karapadites karapadensis, subzone of Maorites aemilii at Gisement 708, Km 8400 de la Coupe Ampamba-Antsirasira (Belo sur Tsiribihina). I, UBGD from the lower Campanian, level of the base of Neogauthiericeras zafimahovai at Gisement 202, Coupe de Berere II (Belo sur Tsiribihina). All 1.

18 106 African Natural History, Volume 3, 2007 Fig. 13. A E, M, Amapondella amapondense (van Hoepen, 1921). A B, UBGD276282, C, UBGD , D E, UBGD , all from the lower Campanian, Zone of Karapadites karapadensis, Subzone of Scaphites reesidei at Gisement 190, Coupe de Berere II (Belo sur Tsiribihina). M, UBGD , from the lower Campanian, Zone of Karapadites karapadensis, Subzone of Maorites aemilii at Gisement 166, Coupe de Berere I (Belo sur Tsiribihina). F L, Ankinatsytes yabei Collignon, F H, UBGD from locality 167 (Belo sur Tsiribihina). I, UBGD , J, UBGD , both from Gisement 334, Beantaly, (Belo sur Tsiribihina). K L, The holotype, UBGD figured by Collignon (1965: 16, pl. 420 (fig. 1738)) from the lower Coniacian, Zone of Peroniceras dravidicum at Gisement 263, Masiaposa (Belo sur Tsiribihina). All 1.

19 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 107 Fig. 14. A K, Eodidymoceras enigma sp. nov. A C, The holotype, UBGD (251/7). D E, UBGD (251/2). F G, UBGD (251/9). H I, UBGD (251/8). J K, UBGD (251/2). All from the lower Campanian Zone of Anapachydiscus wittekindi and Eulophoceras jacobi, Subzone of Besairiella besairiei at Gisement 251, Coupe de Bevaho (Belo sur Tsiribihina). All 1.

20 108 African Natural History, Volume 3, 2007 Fig. 15. A N, Eodidymoceras enigma sp. nov. A C, UBGD (251/6). D E, UBGD (251/5). F H, UBGD (251/1). I J, UBGD (251/11) all from the lower Campanian Zone of Anapachydiscus wittekindi and Eulophoceras jacobi, Subzone of Besairiella besairiei at Gisement 251, Coupe de Bevaho (Belo sur Tsiribihina). K N, SAM-PCZ18751 from locality 105, KwaZulu, St Lucia Formation, uppermost Santonian or basal Campanian. All 1.

21 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 109 Family DIPLOMOCERATIDAE Spath, 1926 (= Polyptychoceratinae Matsumoto, 1938; Neocrioceratidae Spath, 1953; Scalaritinae Ward, 1976; Solenoceratidae Cooper, 1994)) Genus Pseudoxybeloceras Wright & Matsumoto, 1954 Type species Hamites quadrinodosus Jimbo, 1894 by original designation (Wright & Matsumoto 1954: 119). Pseudoxybeloceras? stoliczkai (Collignon MS) sp. nov. Fig. 16 Type Holotype, by monotypy, is a giant specimen, UBGD from the middle Santonian, Zone of Texanites hourcqi at Gisement 684, Coupe Ampamba-Antsirasira (Belo sur Tsiribihina), Madagascar. Description This species is based on a giant body chamber fragment with maximum Wh = 87 mm and Wb = ca. 55 mm. The flanks are covered with fine, rectiradiate ribs, with a rib index of about 21. These bear irregularly spaced, radially elongated ventrolateral tubercles, and large, rounded, ventral tubercles numbering seven per whorl height. Discussion As far as large size and ribbing on the flanks are concerned, the specimen is similar to the giant example of Pseudoxybeloceras quadrinodosum (Jimbo, 1894) figured by Matsumoto (1977, pl. 57 (fig. 2)). That species differs in having tubercles on each rib on the venter and ventrolaterally, in comparison to the irregular ventrolateral tuberculation and large size of the ventral tubercles in P.? stoliczkai. The specimen bears a label in Collignon s handwriting describing it as Pseudoxybeloceras stoliczkai nov. sp. (cf. Stol. pl. 90, fig. 3, 3a). Stoliczka (1866, pl. 90 (fig. 3, 3a)) described and figured a large specimen from the calcareous sandstones near Odium: Ootatur Group as Hamites cf. Meyerati, Ooster. That specimen is quadrituberculate, and obviously a Pseudoxybeloceras, but is more coarsely ribbed. P.? stoliczkai, has atypical Pseudoxybeloceras s.s. ornamentation in not bearing tubercles on every rib, and in the difference in size between the ventrolateral and ventral tubercles, and may possibly be regarded as morphologically transitional to Neocrioceras. Occurrence Middle Santonian, Madagascar. Pseudoxybeloceras sp. Fig. 17A B Material A single, curved specimen, UBGD , labelled Hourcq Berere Description and discussion The locality suggests that the specimen is from the Campanian, and probably lower Campanian, of Berere. The presence on each rib of a pair of ventrolateral and ventral tubercles indicates that this is a representative of Pseudoxybeloceras. It differs from P. quadrinodosum in its stronger ornament. The ventral tubercles are situated very close to each other on either side of the ventral midline. One of these rows of ventral tubercles is slightly stronger than the other, and we suspect that this may be pathological. Occurrence Probably lower Campanian of Madagascar. Genus Schlueterella Wiedmann, 1962 Type species Ancyloceras pseudoarmatum Schüter, 1872 by original designation (Wiedmann (1962: 205). Schlueterella compressum Klinger, 1976 Fig. 9C, 18C D 1976 Neocrioceras (Schlueterella) compressum Klinger, p. 74, pl. 33 (fig. 5); text-figs 8j, 10g Neocrioceras (Schlueterella) compressum Klinger; Immel et al. p. 25, pl. 9 (fig. 3); pl. 10 (figs 1 4); pl. 11 (fig. 3) Neocrioceras (Schlueterella) compressum Klinger; Haggart, p. 263, pl. 30 (figs 1 5); text-fig Neocrioceras (Schlueterella) compressum Klinger; Kennedy & Cobban, p. 65, pl. 10 (figs 1 2); pl. 12 (figs 4 7); text-fig. 25c Neocrioceras (Schlueterella) compressum Klinger; Kennedy, p. 430, pl. 27 (figs 13 15); pl. 29 (figs 4 7) Neocrioceras (Schlueterella) compressum Klinger; Klinger & Kennedy, p. 315, figs 59, 60a c, 61, 63c e Neocrioceras (Schlueterella) compressum Klinger; Kaplan et al., p. 114, pl. 52 (fig. 4). Type Holotype is SAS H19/1, the specimen figured by Klinger (1976, pl. 33 (fig. 5) text-figs 8j,10g) from locality 94, KwaZulu, St Lucia Formation, Santonian I. Material UBGD , a giant specimen from the middle Santonian, Zone of Texanites hourcqi at Gisement 275, km de Coupe Ampolipoly-Antsirasira-Behamotra (Belo sur Tsiribihina); WGC1289 from the Coniacian of Toliara, Betioky. Description and discussion Since its first description from KwaZulu by Klinger (1976), the species has been recorded from various localities ranging from the middle Coniacian to uppermost Santonian or basal Campanian in Pondoland (Eastern Cape Province, South Africa), Madagascar, the Gosau Basin of Austria, Corbières, (France), northern Germany, Wyoming, California and Japan (Matsumoto & Miyauchi 1984: 63). These descriptions illustrate the consecutive ontogenetic stages, starting with a wide, low open helix, followed by curved to straight sections that may reach a very large diameter, and details of the ornament. A gigantic specimen from the middle Santonian of Gisement 275 in Madagascar was illustrated by Klinger &

22 110 African Natural History, Volume 3, 2007 Fig. 16. Pseudoxybeloceras? stoliczkai (Collignon MS) sp. nov. The holotype, UBGD from the middle Santonian, Zone of Texanites hourcqi at Gisement 684, Coupe Ampamba-Antsirasira (Belo sur Tsiribihina). All 1. Kennedy (2003, fig. 61) (Fig. 18C D). The earliest ontogenetic stage was figured by Spath (1921, pl. 7 (fig. 6a c)) and Klinger & Kennedy (2003, fig. 63c e). Here ornament typically consists of looped ribs and spinose tubercles. The tubercles apparently have a septate base, and are seldom preserved in later stages of growth. In exceptional cases, these spines are preserved in later ontogenetic stages, as illustrated in a specimen from the middle Santonian of California by Haggart (1984, pl. 30 (fig. 4)). The specimen from the Coniacian of Betioky shows similar preservation (Fig. 9C). The spines are long and pointed, and orientated in a rather haphazard manner; already commented on by Matsumoto & Miyauchi (1984: 63), and connected over the venter by irregular and diagonally arranged bi- or trifurcating ribbing in a

23 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 111 Fig. 17. A B, Pseudoxybeloceras sp. UBGD , C D, Schlueterella sp. aff. S. tenuiannulatum Collignon, UBGD Both from the lower Campanian at Berere. Both 1. zig-zag manner. In addition, some spines seem to be distinctly curved. We are not sure if this curvature of the spines reflects the original ornament or whether it may in part be due to diagenetic deformation. Judging by the fragile nature of the spines we suspect the former. Occurrence Upper Coniacian and lower Santonian of KwaZulu, Santonian of Pondoland; Coniacian and middle Santonian of Madagascar, lower Santonian of Austria, middle Santonian of Corbières,(France), uppermost Santonian or basal Campanian, northern Germany; middle Coniacian of Wyoming; middle Santonian, California and Santonian of Japan (Matsumoto & Miyauchi 1984: 63). Schlueterella sp. aff. S. pseudoarmatum (Schüter, 1872) Fig. 18A B Compare: 1872 Ancyloceras (?) pseudoarmatum Schlüter, p. 99, pl. 31 (figs 1 3) Neocrioceras (Schlueterella) pseudoarmatum (Schlüter); Kaplan et al. p. 116, pl. 48 (fig. 1); pl. 49 (fig. 5); pl. 50 (figs 1 3); pl. 51 (figs 1, 4, 5) (with synonymy). Material A single fragment, UBGD from the lower Campanian of Gisement 166, Coupe de Berere I (Belo sur Tsiribihina), Madagascar.

24 112 African Natural History, Volume 3, 2007 Fig. 18. A B, Schlueterella sp. aff. S. pseudoarmatum (Schlüter, 1872). UBGD from the lower Campanian at Gisement 166, Coupe de Berere I (Belo sur Tsiribihina). C D, Schlueterella compressum Klinger, UBGD from the middle Santonian at Gisement 275. Both 1.

25 Klinger et al.: Nostoceratidae and Diplomoceratidae (Cephalopoda: Ammonoidea) from Madagascar 113 Description The fragment has part of a septum preserved, and appears to represent the beginning of the body chamber. It has a circular whorl section (Wb:Wh = 70:70), a rib index of 11 and four rows of rounded to slightly radially elongated tubercles situated on narrow, radial looped ribs, separated by two to three non- tuberculate ribs. The tubercles are poorly developed on the venter and strongest at midflank The tuberculate and non-tuberculate ribs are of equal strength. Discussion This specimen seems closest to Schlueterella pseudoarmatum, best known from the upper Campanian of Germany, as far as rib density and spacing of tubercles is concerned. That species, however, appears to have a depressed whorl section and stronger tuberculation. Unfortunately, all of the German type specimens have suffered from diagenetic deformation to some extent and are difficult to compare with the present specimen. A specimen of comparable size was illustrated by Kaplan et al. (2005, pl. 49 (fig. 5)). Another comparable species is Schlueterella kawada Matsumoto & Miyauchi (1984: 61, pl. 26 (fig. 1); pl. 27 (figs 3 4); pl. 28 (fig. 2); pl. 29 (fig. 1); pl. 30 (figs 1 2); pl. 31 (fig. 3); text-fig. 9) from the upper Campanian of northern Hokkaido. It has a similar circular whorl section, but has the tubercles arranged in zig-zag fashion. Because of its occurrence in the lower Campanian as compared to the upper Campanian occurrence of S. pseudoarmatum, it is best to refer to the specimen as Schlueterella sp. aff. S. pseudoarmatum. Occurrence Lower Campanian, Madagascar. Schlueterella sp. aff. S. tenuiannulatum Collignon, 1969 Fig. 17C D Compare 1969 Neocrioceras (Schlueterella) tenuiannulatum Collignon, p. 44, pl. 530 (fig. 2089). Material UBGD , from the lower Campanian of Berere, Madagascar. Description The material available consists of a single, curved septate specimen. The whorl section is oval, slightly higher than wide (Wb:Wh = 40:44), ornamented by thin, single, radial ribs, with a rib index of 13. Low, rounded tubercles are situated on pairs of looped ribs, separated by two to six non-tuberculate ribs. Discussion Because of differences in size and preservation, it is difficult to relate the present specimen to S. tenuiannulatum and to S. sp. aff. S. pseudoarmatum described above. Schlueterella tenuiannulatum is based on a holotype which is half the diameter of the present specimen. The ribbing appears to be finer and the tubercles less prominent in the holotype of S. tenuiannulatum, but the rib index and whorl section are comparable, and the present specimen is probably only a more adult form of that species. Schlueterella sp. aff. S. pseudoarmatum is much more coarsely ornamented, but again, this may be an artifact of different ontogenetic stages. Occurrence Lower Campanian, Madagascar. ACKNOWLEDGEMENTS Financial assistance to Klinger from the National Research Foundation, South Africa and the Service de Cooperation et d Action Culturelle, France for travelling and subsistence costs in Dijon in 1999 is gratefully acknowledged. A special word of thanks to Dr Jean-Henri Delance, and numerous colleagues at the Institut des Sciences de la Terre, Université de Bourgogne (Dijon) for their assistance during Klinger s stay there. And to Dr J. Thomas for assistance with the catalogue numbers. Kerwin van Willingh assisted with the photography. Kennedy thanks the staff of the Oxford University Museum of Natural History. REFERENCES BASSE, É Sur quelques Mollusques crétacées des Corbières méridionales. Bulletin de la Société Géologique de France, (5)9(1 3): 35 58, pl. 3. 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Smithsonian Miscellaneous Collections 227: i xvi, GROSSOUVRE, A. DE Recherches sur la craie supérieure: 2.