Cuticulas fosiles de nilsonia

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[Palaeontology, Vol. 50, Part 5, 2007, pp. 1299–1318]

FIRST RECORD OF NILSSONIOPTERIS (GYMNOSPERMOPHYTA, BENNETTITALES) FROM THE CARNIAN (UPPER TRIASSIC) OF LUNZ, LOWER AUSTRIA
by CHRISTIAN POTT*, MICHAEL KRINGS  and HANS KERP*
¨ ¨ ¨ ¨ ¨ ¨ ¨ *Forschungsstelle fur Palaobotanik am Geologisch-Palaontologischen Institut, Westfalische Wilhelms-Universitat Munster, Hindenburgplatz 57, D-48143Munster, Germany; e-mails: christian.pott@uni-muenster.de, kerp@uni-muenster.de ¨ ¨  Bayerische Staatssammlung fur Palaontologie und Geologie und GeoBio-CenterLMU, Richard-Wagner-Straße 10, D-80333 Munich, Germany; e-mail: m.krings@lrz.uni-muenchen.de Typescript received 26 July 2006; accepted in revised form 6 November 2006

Abstract: The Carnian (Late Triassic) flora of Lunz in Lower Austria isfamous for an abundance of well-preserved bennettitalean and cycadalean foliage and reproductive structures. However, only the fertile remains have been studied in detail to date. Recently completed systematic macromorphological and cuticular analyses of leaf fossils from Lunz revealed that several forms previously accommodated in the genus Macrotaeniopteris do not represent ferns but ratherBennettitales assignable to the genus Nilssoniopteris. We describe three species of Nilssoniopteris, which represent the first records for this genus from Lunz, and one of the earliest

accounts of Nilssoniopteris in the Northern Hemisphere. The following new combinations are introduced: Nilssoniopteris haidingeri (Stur ex Krasser, 1909a) comb. nov., N. angustior (Stur ex Krasser, 1909a) comb. nov. andN. lunzensis (Stur ex Krasser, 1909a) comb. nov. The discovery of Nilssoniopteris further substantiates the significance of the Lunz flora as one of the richest and most diverse early Late Triassic floras from the Northern Hemisphere.
Key words: cuticle, Macrotaeniopteris, Taeniopteris, fossil plants, Carnian, Triassic, Lunz.

The well-known Carnian (early Late Triassic) flora from
Lunz in LowerAustria contains several morphotypes of elongate, entire-margined to coarsely pinnate leaves, most of which have historically been interpreted as belonging to marrattialean ferns (Krasser 1909a). The earliest record in the literature of these leaf types is in a species list (Stur 1885); however, no diagnoses, descriptions or illustrations were given. In this list, Stur (1885) referred six foliagemorphotypes to the genus Taeniopteris Brongniart, 1828. The names given by Stur, however, remained nomina nuda until Krasser (1909a), based on Stur’s handwritten notes, provided diagnoses for the taxa and a short discussion, but without illustrating the material. He also transferred the six species to the morphogenus Macrotaeniopteris Schimper, 1869. Macrotaeniopteris was introduced by Schimper(1869) for entire-margined fronds previously accommodated in Taeniopteris auct. nec Brongniart. Schimper assigned Macrotaeniopteris to the Marattiales, but subsequent studies (e.g. Florin 1933a) revealed that some forms, e.g. several specimens described as M. gigantea Schimper, 1869, in fact represent cycadalean foliage.

Although cuticular analysis is known to provide a wealth of information usefulin determining the systematic affinities of many late Palaeozoic and Mesozoic compression foliage fossils (e.g. Harris 1932; Florin 1933a, b; Kerp 1990; Watson and Sincock 1992; Krings and Kerp 2000; Krings et al. 2005; Watson and Cusack 2005), it has largely been neglected in studies of the Lunz flora. Data on the epidermal anatomy of the proposed Macrotaeniopteris leaves were absent, with theexception ¨ of a few fragmentary cuticles described by Krausel (1920). ¨ However, Krausel’s descriptions are incomplete and, hence, not very useful as a tool for accurately identifying further specimens that may be similar in overall appearance. As a result, the circumscription of the six foliage types from Lunz assigned to Macrotaeniopteris by Krasser (1909a) continued to be vague, and thus the...
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