The Cyclopteris of Laveineopteris (Late Carboniferous pteridosperm). Fancies and facts: methodological and taxonomical implications

Cyclopterid folioles commonly borne on the fronds of Late Carboniferous neuropterid plants were recently interpreted as entire shade leaves that were, among the taxa exhibiting a neuropteroid pinnate foliage, only present in the medullosalean genus Laveineopteris. Numerous speculations concerning the physiology, growth habit, ecology and the reconstruction of the Laveineopteris plant were derived from this assertion. It is shown in this paper that this assertion is inaccurate. Cyclopterids are not entire leaves. They are heteromorphic folioles confined to the fronds, and mainly located in the proximal parts of them. They are homologous to ultimate pinnae sometines being slightly bipinnatifid at the base. In addition to a photosynthetic role, cyclopterids were also playing a protective role for the circinately coiled pinnate foliage segments during the early differentiation of the fronds. It is also shown that cyclopterids are not restricted to the sole genus Laveineopteris among the neuropterids. The cuticular information on which several recent taxonomic treatments of the neuropterids were based is critically analyzed and found inadequate. The diagnoses of several neuropterid taxa are emended

Mise au point sur Palaeoweichselia defrancei (ptéridospermée du Carbonifère), à partir d'un bel échantillon récolté dans le bassin houiller du nord de la France / Up to date look at Palaeoweichselia defrancei (Carboniferous pteridosperm), generated by a nice specimen recorded from the Northern France coal field

For a long time, the species Palaeoweichselia defrancei (Brongniart) was considered endemic to the Saar-Lorraine coalfield, and mainly localized in the upper Westphalian C/lower Westphalian D interval. The record, in the Northern France coal Field, of a nice specimen belonging indisputably to that species confirms again the conclusions presented by Laveine, Coquel and Loboziak in 1977. The information furnished by that specimen, together with the discoveries made in the Saar-Lorraine coal field during the last twenty years, justify an updating of our knowledge related to that taxon. It concerns not only its principal morphological characteristics, but also its vertical extension and palaeogeographical distribution. Some hypotheses on its eventual relationships with other Carboniferous pteridosperms are discussed.Pendant longtemps l'espèce Palaeoweichselia defrancei (brongniart) a été considérée comme une espèce endémique au bassin houiller sarro-lorrain, et essentiellement localisée dans l'intervalle Westphalien С supérieur/Westphalien D inférieur. La découverte, dans le bassin houiller du Nord de la France, d'un bel échantillon appartenant incontestablement à cette espèce vient confirmer à nouveau les conclusions avancées par Laveine, Coquel et Loboziak en 1977. Les informations apportées par cet échantillon et les découvertes faites au cours des vingt dernières années dans le bassin sarro-lorrain permettent de présenter une mise à jour de nos connaissances sur ce taxon, non seulement pour ce qui concerne ses principales caractéristiques morphologiques, mais aussi sur sa répartition stratigraphique et sa distribution paléogéographique. Quelques hypothèses sur ses liens de parenté avec d'autres ptéridospermées du Carbonifère sont présentées.Laveine Jean-Pierre, Goubet Pierre. Mise au point sur Palaeoweichselia defrancei (ptéridospermée du Carbonifère), à partir d'un bel échantillon récolté dans le bassin houiller du nord de la France / Up to date look at Palaeoweichselia defrancei (Carboniferous pteridosperm), generated by a nice specimen recorded from the Northern France coal field. In: Sciences Géologiques. Bulletin, tome 48, n°1-3, 1995. Paléobotanique et palynologie du Permo-Carbonifère et du Trias / Palaeobotany and Palynology of the Permo-Carboniferous and the Triassic sous la direction de Raymond Rauscher . pp. 21-47

Jacques Chalard (1921 – 2010)

International audienceMonsieur Jacques Chalard, membre de la Société Géologique du Nord, et l’un des acteurs majeurs de la phalange des géologues houillers qui ont contribué, après la Seconde guerre mondiale, à gagner la ‘bataille du charbon’ dans le Bassin houiller du Nord-Pas-de-Calais, nous a quittés le 16 Novembre 2010. Le présent portrait va tenter de retracer brièvement la vie et le parcours professionnel et scientifique de cet éminent collègue, dont le talent n’avait d’égal que sa pudeur et sa discrétio

Frond architecture of the seed-fern Macroneuropteris scheuchzeri, based on Pennsylvanian specimens from the Northern France coal field

International audienceAn exceptional collection of remarkably informative specimens of Macroneuropteris scheuchzeri from the Bolsovian (ex Westphalian C) of the Northern France coal field shows a bifurcate semi-pinnate type of frond architecture. This collection allows the circumscription of the variability of the main characters of the frond. Reconstructions of the frond and of the whole plant are proposed. Morphological, taxonomical, and palaeogeographical implications are analyzed

Association of entire orbicular cyclopterids with Neuropteris ovata pinnate foliage from the late Pennsylvanian (Stephanian) of West Virginia, USA: taxonomical implications

A large shale covered with abundant pinnate remains of Neuropteris ovata foliage also exhibits three detached, entire orbicular cyclopterids. Although disconnected, the close association of these cyclopterids with the pinnate remains supports their probable taxonomic relationship. Consequently, it appears that entire orbicular cyclopterids can also occur on the fronds of the genus Neuropteris sensu stricto and not just on the fronds of Laveineopteris as suggested by some authors. Related taxonomical and palaeoecological implications are briefly discussed

André Dalinval (1920-2015)

International audienceMonsieur André Dalinval nous a quittés le 12 Avril 2015 (Fig. 1). Membre de la Société Géologique du Nord, il fut l’un des acteurs de l’équipe des géologues houillers qui, après la Seconde Guerre Mondiale, ont contribué à gagner la « bataille du charbon » dans le Bassin houiller du Nord - Pas-de-Calais.Le présent portrait va tenter de retracer brièvement la vie et le parcours professionnel et scientifique de cet éminent collègue

Frond architecture of two remarkable specimens of the pteridosperm Laveineopteris rarinervis from the Late Carboniferous (early Westphalian D) of Piesberg near Osnabrück (Germany): morphological implications

Two remarkable specimens of Laveineopteris rarinervis (later synonym: L. (Neuropteris) piesbergensis) exhibit clearly the characteristics of the bifurcate semi-pinnate type of frond architecture. One of the specimens supports the homology of the cyclopterids with ultimate rachial pinnae. Related morphological and taxonomical implications are briefly analyzed

La biostratigraphie du Paléozoïque et le temps

Babin Claude, Laveine Jean-Pierre, Lemoigne Yves, Zhang S. La biostratigraphie du Paléozoïque et le temps. In: Documents des Laboratoires de Géologie, Lyon. Hors-série n°9, 1990. Journée Louis David (16 novembre 1988) pp. 23-44