Terebratulida, Brachiopoda) from Belgium and the Netherlands
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BULLETIN DE L’INSTITUT ROYAL DES SCIENCES NATURELLES DE BELGIQUE SCIENCES DE LA TERRE, 74: 105-118, 2004 BULLETIN VAN HET KONINKLIJK BELGISCH INSTITUUT VOOR NATUURWETENSCHAPPEN AARDWETENSCHAPPEN, 74: 105-118, 2004 A new Late Maastrichtian species of Cyranoia (Terebratulida, Brachiopoda) from Belgium and The Netherlands by Eric SIMON Sim on, E., 2004. - A new Late Maastrichtian species of Cyranoia list by the same author of all taxa (flora and fauna) known (Terebratulida, Brachiopoda) from Belgium and The Netherlands. then from the Maastrichtian chalk. Although very rich Bulletin de l ’Institut royal des Sciences naturelles de Belgique, Sciences de la Terre, 74: 105-118, 2 pis, 3 figs., Bruxelles-Brussel, brachiopod collections from the Maastrichtian type area March 31, 2004. - ISSN 0374-6291. are housed in the Natuurhistorisch Museum Maastricht (NHMM) and in the Institut royal des Sciences naturelles de Belgique in Brussels (IRScNB), only a handful of Abstract studies on this subject have appeared during recent years. This material is in urgent need of revision and would Representatives of a new Late Maastrichtian species of the terebratulid greatly add to our current knowledge of temperate Cre brachiopod Cyranoia C o o p er, 1983 are described from the Meerssen taceous brachiopod faunas. Member (Maastricht Formation) of the Maastricht area (southern Lim burg, The Netherlands) and from Vroenhoven (province of Limburg, Within this framework, several specimens of a tereb Belgium). This new taxon is amongst the largest brachiopods ever ratulid brachiopod are singled out here, collected (Fig. 1) recorded from Upper Cretaceous strata. The structure of its loop is from the Meerssen Member (Maastricht Formation) in the illustrated by transverse serial sections and by preparation of one specimen. The assignment of this species to the genus Cyranoia Maastricht area (southern Limburg, The Netherlands) and C o o p er, 1983 is discussed in detail. from Vroenhoven (province of Limburg, Belgium). The biozonation of the Meerssen Member has recently been Key words:Brachiopods, Rectithyridinae, Cretaceous, Upper Maas J a g t trichtian, Maastricht, new species. described by ( 1999) who noted the co-occurrence of coleoids of the Belemnitella junior group and Belemnella (Neobelemnella) kazimiroviensis sensu J e l e t z k y , 1951. This association assigns a Late Maastrichtian age to this Résumé unit. The terebratulid brachiopod species described was not Cet article présente une nouvelle espèce de brachiopode térébratulide appartenant au genre Cyranoia C o o p er, 1983. Elle est datée du Maas- listed by B o s q u e t , although in the Maastricht area it is trichtien Supérieur et elle fut collectée dans la Craie de Meerssen not exceptionally rare, and mostly well preserved (articu (Formation de Maastricht) de la région de Maastricht (Pays-Bas) et lated). Three specimens, studied for internal structures, de Vroenhoven (province du Limbourg, Belgique). Ce nouveau taxon compte parmi les plus grands brachiopodes découverts dans les terrains reveal an intact brachidium. du Crétacé Supérieur. La structure du brachidium est établie par la In his 1860 list, B o s q u e t referred to just four species of réalisation de sections transversales sériées. L’appartenance de cette large terebratulide brachiopods, namely Terebratula car espèce nouvelle au genre Cyranoia est discutée en détail. nea J. Sowerby, 1812 (= Carneithyris carnea in current Mots-clefs: Brachiopodes, Rectithyridinae, Crétacé, Maastrichtien nomenclature), Terebratula fittoni von Hagenow, 1842 Supérieur, Maastricht, espèce nouvelle. (= Neoliothyrina fittoni), Terebratula sowerbyi VON H a g e n o w , 1842 (= Neoliothyrina obesa S a h n i, 1925) and Terebratula scaphula von Schlotheim, 1813. The last- Introduction named species is a member of the Rectithyridinae, repre sented by a ventral valve illustrated by Faujas de Saint- Faujas de Saint-Fond (1803?)was the first author to F o n d (1803, pi. 26, fig. 8). It may be that B o s q u e t ( 1860, briefly describe and illustrate Late Maastrichtian bra item number 582) attributed the species described in the chiopods from the Maastricht area. Subsequently, von present paper to T. scaphula, based on the poor illustra Schlotheim (1813)discussed and named these, referring tion given by Faujas de Saint-Fond. It should be to F au jas’s illustrations. The most important contribu noted, however, that features visible in this illustration tions to our knowledge of Maastrichtian brachiopods preclude assignment of the new terebratulid to T. sca from the type area, however, are B o sq u e t’s papers, pub phula as interpreted here (see below). lished in 1854and 1859.In 1860appeared an exhaustive Recently, the new species was briefly discussed and 106 Eric SIMON BELGIUM THE NETHERLANDS KUNRADE Geui Maastricht Valkenburi ¡VROENHOVEN Gulpen • A * m Eben-Emaal *) / £ BELGIUM 5 km Fig. 1 — Map of the Maastricht area, showing the location of Vroenhoven (province of Limburg, Belgium) and of the ENCI quarry near Maastricht (southern Limburg, The Netherlands). n = Collecting places of specimens of Cyranoia bosqueti n. sp. illustrated by Robert (1995, p. 60, fig. 78) under the Maastrichtian) at Ciply (Mons Basin, Province of Hainaut, name o f “Rectithyris” sp. However, a detailed analysis Belgium). of the loop shows that this brachiopod cannot be placed in Transverse serial sections were prepared (see A g e r , 1965, the genus Rectithyris Sahni, 1929. pp. 212-218 for procedure) and peels were taken on cellulose acetate following the method described by Sternberg & B el- The genus Cyranoia Cooper, 1983 on the other hand, ding (1942). Peels of the serial sections are in the NHMM shows several interesting features which can also be collections. One specimen was carefully prepared to expose found in the present form. Assignment to this genus is the brachidium. confirmed by the presence of inner hinge plates and the Suprafamilial classification follows W illiam s et al. (1996). general structure of sockets and cardinalia seen in this The synonymy list is presented following the recommendations new species of brachiopod. of M atthew s (1973). Material and methods Taxonomic description Sixteen articulated specimens have been studied, five of which Phylum Brachiopoda D u m e r il , 1806 are from the St-Pietersberg, south of Maastricht, three from Subphylum Rhynchonelliformea W i l l i a m s et al., 1996 the ENCI quarry near Maastricht, five from the Ankerpoort- Class Rhynchonellata W i l l i a m s et al., 1996 Marnebel quarry at Eben-Emael (province of Liège, Belgium) from dumped material originally excavated at Vroenhoven Order Terebratulida W a a g e n , 1883 (Albert Canal extension works, province of Limburg, Belgium), Suborder Terebratulidina W a a g e n , 1883 two relatively small specimens from Maastricht (lacking pre Superfamily Terebratuloidea G r a y , 1840 cise data) preserved in the collection of G. Willems (Berzée, Family Terebratulidae G r a y , 1840 Belgium) and one from the Tuffeau de Saint-Symphorien (Late Subfamily Rectithyridinae M u i r - W o o d in M o o r e , 1965 A Late Maastrichtian species of Cyranoia 107 Genus Cyranoia C o o p e r , 1983 cult to do correctly and precisely. They also demonstrated that some characters considered as very important by Type species: Terebratula depressa visae H a d d in g , 1919 C o o p e r (1983) are in fact very variable among indivi duals within the same species. This is the case for the loop Note: C o o p e r (1983) used different spellings, namely angle which may vary within a species to a much greater “ Terebratula depressa vissae H a d d in g , 1919” (pp. 185, extent than suggested by C o o p e r (1983). This indicates 214) and “ Cyranoia vissae (Hadding)” in the caption to that several measurements of the loop angle are required his plate 21. However in the caption to plate 54, the trivial to provide a valid basis for describing a new genus. As a name is spelt “ viassae” .Following H a d d i n g (1919, significant statistical analysis of the variation of the loop p. 20), the correct spelling would be “visae” . angle value and other characters within the material available for C. bosqueti n. sp. is not possible, the erection C o o p e r (1983, p. 185) established his new genus Cyra of a new genus should be avoided. noia on the basis of a few distinctive characters, describ In his detailed description of C. visae, C o o p e r (1983, ing it as a ‘‘Terebratulacea with exterior like that of p. 185) insisted that the outer hinge plates are narrow, a Rectithyris, with long beak, round, uncovered symphy- character not included in his diagnosis, writing “ ...outer tium” . Four characteristics are then listed, “ short outer hinge plates are narrow, a mere connective dorsally weld hinge plates, wide loop, strong development of inner ing the high crural bases and socket ridges, the combination hinge plates, socket ridges not extended laterally” . producing narrow V-shaped troughs” . Specimen USNM At first glance, the internal loop characters observed in 112312b ( C o o p e r , 1983, pi. 21, figs. 25-26) matches this C. bosqueti n. sp. are far removed from this meagre description perfectly because the outer hinge plates are description. The outer hinge plates are rather long, the extremely narrow. Such a structure is also visible on the loop is relatively narrow, and the inner hinge plates are drawing of a loop ( C o o p e r , 1983, pi. 66, fig. 2). In contrast, moderately developed. Moreover, in one specimen (ex specimen USNM 550948a ( C o o p e r , 1983, pi. 21, fig. 21) ceptional), the socket ridges are moderately extended exhibits much wider outer hinge plates, the outer hinge laterally as in the genus Rectithyris.