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Chondrichthyes, Elasmobranchii) Fossil Record 10(2) (2007), 190–194 / DOI 10.1002/mmng.200700005 Bransonelliformes — a new order of the Xenacanthimorpha (Chondrichthyes, Elasmobranchii) Oliver Hampe*,1 and Alexander Ivanov**,2 1 Museum fu¨ r Naturkunde der Humboldt-Universita¨t zu Berlin, Invalidenstraße 43, D-10115 Berlin, Germany 2 Department of Palaeontology, St. Petersburg University, 16 Linija 29, St. Petersburg 199178, Russia Received 18 December 2006, accepted 21 February 2007 Published 1 August 2007 With 2 figures, 1 table Key words: Xenacanthimorpha, Bransonella, Barbclabornia, phylogeny. Abstract The order Bransonelliformes is erected for the genera Bransonella Harlton, 1933 and Barbclabornia Johnson, 2003 based on the distinct characters of an inverted “V”-nested pattern of ornamentation preliminary on the labial aspect at the tooth cusps, the presence of labial foramina, and the occasional occurrence of a centrally positioned lingual opening of a main nutrient canal at the bases of the teeth. The Bransonelliformes comprises the primitive sister group to the Xenacanthiformes within the Xenacanthimorpha. Schlu¨ sselwo¨ rter: Xenacanthimorpha, Bransonella, Barbclabornia, Phylogenie. Zusammenfassung Fu¨ r die Gattungen Bransonella Harlton, 1933 und Barbclabornia Johnson, 2003 wird die neue Ordnung Bransonelliformes eingefu¨ hrt basierend auf den Merkmalen von bevorzugt auf der labialen Seite der Zahnspitzen auftretenden, dachziegelartig ineinander geschachtelten Skulpturleisten, dem Vorhandensein labialer Foramina sowie dem ha¨ufigen Auftreten einer gro¨ ßeren lingualen ffnung an der Zahnbasis, dem Durchtritt eines zentralen Na¨hrkanals. Die Bransonelliformes stellen die urspru¨ ng- lichere Schwestergruppe zu den Xenacanthiformes innerhalb der Xenacanthimorpha dar. # 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Updated knowledge (Tway & Zidek 1983, as “Subtype 173” in an ich- thyolith catalogue) and from early Permian strata Bransonella is an elasmobranch genus known only of Kansas (Schultze 1985, as Xenacanthus lueder- from teeth. It has a tricuspid crown and a lingually sensis), and B. lingulata from Vise´an deposits of the extended base with a coronal button on the upper Kuznetsk Basin (Rodina & Ivanov 2002) and Ser- side and a basal tubercle situated on the bottom pukhovian rocks of the Moscow syneclise (Ivanov side as is typical for xenacanthiform teeth. Three & Ginter 1996). B. nebraskensis was identified also species are recognized to date: the early Pennsylva- from Vise´an sediments of the Nearpolar and South nian B. tridentata from Oklahoma (Harlton 1933, Urals (Ivanov & Ginter 1996), the Kuznetsk Basin first identified as a conodont), B. nebraskensis from (Rodina & Ivanov 2002) in Russia, the Holy Cross late Pennsylvanian deposits of Nebraska (Johnson Mountains in Poland (Ivanov & Ginter 1996), and 1984, as Xenacanthus? nebraskensis) and Kansas from the Dinant synclinorium in Belgium (Derycke * Corresponding author: e-mail: [email protected] ** E-mail: [email protected] # 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Fossil Record 10(2) (2007) 191 inverted “V”-nested pattern of ornamentation A B E F labial foramina C D G H 200 µm lingual notch central opening of main nutrient canal Fig. 1. Typical teeth of Bransonella (A––D) and Barbclabornia (E––H) and their characteristic features. A –– Bransonella lingu- lata, LP 16-3, from Kalinovskie Vyselki Quarry, Moscow Syneclise, Russia (Serpukhovian, late Mississippian), in labial view; B –– Bransonella nebraskensis, TMM 41648-139, in labial view; C –– Bransonella nebraskensis, TMM 41647-20, in lingual view, both from Nemaha County, Nebraska, USA (Virgilian ¼ Gzhelian, late Pennsylvanian); D –– Bransonella nebraskensis, LP 16- 2, from Kozhim River, Polar Urals, Russia (Visean, Mississippian), in lingual view; E –– Barbclabornia luedersensis, SMU 64112, from Wolf Creek, Texas, USA (Artinskian, Cisuralian), in labial view; F –– Barbclabornia luedersensis, SMNS 52067.1, from Jefferson County, Oklahoma, USA (Wolfcampian, Cisuralian), in labial view; G –– Barbclabornia luedersensis, SMU 64101, from Spring Creek, Texas, USA (Artinskian, Cisuralian), in lingual view; H –– Barbclabornia luedersensis, SMU 64056, from West Franklin Bend, Texas, USA (Artinskian, Cisuralian), in lingual view. Drawings based on figures from Ivanov & Ginter (1996: A, D), Johnson (1984; B, C; 2003: E, G, H) or are from the first author (F). Abbreviations: LP (Laboratory of Palaeontology, St. Petersburg University, Russia); SMNS (Staatliches Museum fu¨ r Naturkunde, Stuttgart, Germany); SMU (Southern Methodist University, Dallas, Texas); TMM (Texas Memorial Museum, University of Texas, Austin). et al. 2005), as well as from Moscovian deposits of North China (middle Famennian), Ivanov (1999) the Moscow syneclise, Russia (Lebedev 2001). Ad- from Timan-Pechora Province, Russia (early Tour- ditional teeth and tooth fragments certainly belong- naisian), Ginter (2001) from Utah, USA (late Famen- ing to Bransonella are reported from Mississippian nian), and Ginter et al. (2002) from Dalmeh, Iran sediments of North Qilian Mountain in China (late Famennian). Some of these may belong to the (Wang et al. 2004), from Pennsylvanian deposits of Jalodontidae (phoebodontiform sharks, known by the Amazon Basin in Brazil (Duffin et al. 1996, as teeth having an ornament of the cusps similar to ?Triodus sp.) and of the Bu¨ kk Mountains in Hun- that of Bransonella, but with a different morphol- gary (Kozur 1984, as Xenacanthus sp.). ogy of the base; Ginter et al. 2002), while others The resemblance to Bransonella, due to poor or might be an early form of Bransonella. corroded preservation, is questionable in remains Species of Bransonella share some peculiar char- described by Ji & Ziegler (1992) from Guilin, South acters that never occur in sharks of the order Xena- China (late Famennian), Xia (1997) from Xinjiang, canthiformes. These are the inverted “V”-nested # 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1museum-fossilrecord.wiley-vch.de 192 Hampe, O. & A. Ivanov: Bransonelliformes cusp ornamentation reaching the base, the presence of Bransonella. Subsequently, Hampe et al. (2004) of labially positioned foramina on the base, and the demonstrated a sister group relationship with the lingual position of a large central opening of a Xenacanthidae. Bransonella is defined in their ana- main nutrient canal forming often a distinct notch lysis by the presence of an inverted “V”-nested at the lingual margin of the base. pattern of the cusps and a large central opening of The general tricuspid tooth morphology is the a main nutrient canal at the lingual margin of the reason why Bransonella was often identified as a base. Characters shared with representatives of the xenacanthid in the past. Chronologially, Zidek xenacanthids are regarded as parallel develop- (1973) identified B. tridentata as belonging to the ments. Hampe et al. (2004) assume that Bransonella genus Dittodus. Zangerl (1981) grouped Bransonella and xenacanthids probably shared the same ances- under Xenacanthidae incertae sedis. Johnson (1984) tor, perhaps a phoebodont. Also Ginter (2004) dis- assigned the Nebraskan teeth to the genus Xena- cussed the possibility of a transition from a phoe- canthus, but pointed out similarities to B. tridentata. bodont (ancestor) to the xenacanth dentition, Zidek (1993) then characterised Bransonella as a probably via Bransonella and/or Jalodus, a wide- true xenacanthiform. Schneider (1996) groups the spread tooth genus from the Late Devonian (mid- ‘crushing-type’ teeth in the family Xenacanthidae. dle Fammenian) to Tournaisian, which has a tricus- Ginter & Ivanov (1996) see in Bransonella a repre- pid crown of very strong cusps and the same sentative of the Xenacanthida. Ivanov & Ginter ornamentation as Bransonella. (1996) also followed this position and classify Bran- Another problematic taxon is the newly erected sonella as to be a xenacanthid belonging to the genus Barbclabornia (Johnson 2003), based on a order Xenacanthida and Family indet. However, they species described first by Berman (1970: Xena- mentioned that the characteristic ornamentation of canthus luedersensis). The usually bicuspid teeth of Bransonella does not occur in any other represen- Barbclabornia luedersensis are known from Late tative of the Xenacanthida/Xenacanthiformes [Berg Carboniferous(?) and Early Permian sediments of (1940) established the subclass Xenacanthi and Texas and Oklahoma also show, like teeth of Bran- order Xenacanthiformes. Glikman (1964) was the sonella, an inverted “V”-nested pattern of orna- first author who suggested superordinal rank for mentation, here covering the upper half of the the “Xenacanthi” and used dental characters to cusps concentrated on the labial aspect. Also labial define the superorder and the order “Xenacanthida”. foramina can be present at the base. A centrally The definition of Berg, however, has priority, even positioned canal opening can be situated at the though he used no dental features in his diag- lingual margin of the base or on the surface of the noses.]. Ginter et al. (2002) attributed Bransonella to coronal button (first author, pers. observ.). The Xenacanthiformes and Family indet. as did Wang teeth belong to an elasmobranch of estimated 4.5 to et al. (2004: Xenacanthida and Family indet.). 5 m in total length based on the data of a preserved Hampe (2003) indicated that further information palatoquadrate (see Zidek et al. 2003). Combined and investigation is needed to resolve the position with
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