Intramarginal Veined Lauraceae Leaves From the Albian–cenomanian of Charente‐maritime (Western France)

Abstract

Eucalyptolaurus depreii gen. et sp. nov. is proposed for angiosperm leaves newly collected from uppermost Albian -lowermost Cenomanian of Charente-Maritime (western France). They consist of simple, narrow, elongate laminas with entire margins and intramarginal veins. The epidermal cells of adaxial cuticle shows small, rounded, blunt papillae outward that protrude inward and fuse together as rolls along and parallel to the margins, while the adaxial cuticle bears brachyparacytic stomatal apparatus that exhibit sunken guard cells and hair bases consisting of a thick-walled pore surrounded by radially arranged differentiated cells. Resin bodies occur inside the mesophyll. These characters closely resemble the lauroid taxa 'Myrtophyllum' and Pandemophyllum from the Cenomanian of the Czech Republic and Dakota (USA) respectively. The narrow angle of basilaminar secondaries and the whole suite of features in the guard cells (sunken guard cells embedded into subsidiary cells and stomatal ledges) strongly support close affinity with the Lauraceae. From the Cenomanian lauraceous reproductive organs and their related leaves already showed high disparity and diversity. In addition they displayed a broad ecological range from freshwater floodplains to brackish swamps. This combined to high diversity of reproductive organs suggest ecological radiation of Lauraceae by the Cenomanian.Key words: early salt-tolerant angiosperms, Lauraceae, Eucalyptolaurus, cuticles, mid Cretaceous, western France. Kvaček (1983Kvaček ( , 1992 and Nȇmejc and Z. Kvaček (1975) described both detailed venation and cuticle of Myrtophyllum angustum (Velenovský) Knobloch and M. geinitzii Heer from the Cenomanian and Senonian of Bohemian Cretaceous Basins (Czech Republic), but the diagnosis based on the venation only remained unchanged. M. geinitzii Heer was also reported from the Cenomanian of Alcanede in Portugal (Teixeira 1948(Teixeira , 1950 and the Cenomanian-Turonian of Atane in Greenland (Heer 1883; Boyd 1998). In southeastern France, De Saporta (1862) mentioned leaf impressions similar to M. angustum and M. geinitzii collected from the trench Derbèze at Bagnolssur-Cèze (Gard) in sandstones now considered being Early Coniacian in age (Ducreux et al. 1982). De Saporta (1862 and Fritel (1927) also recognized Eucalyptus-like leaves from the Campanian of Fuveau basin (Bouches-du-Rhô ne, southeastern France). In Northern America, only impressions of M. geinitzii Heer were collected from several localities: Albian-Cenomanian of Dakota group (Lesquereux [Palaeontology, Vol. 52, Part 2, 2009, pp. 323-336] Greuter et al. 2000). Velenovský (1883) described the narrow, elongated lauraceous leaves with intramarginal veins Grevillea constans from the Cenomanian of Bohemian Basin. Velenovský (1889) renamed it Grevilleophyllum, Grevillea being a modern genus without any systematic affinity with the fossil. No diagnosis or description was given, and thus Grevilleophyllum should have fallen into nomen nudum. However Z. Kvaček (1983Kvaček ( , 1992...

Plant-dominated assemblage and invertebrates from the Lower Cenomanian of Jaunay-Clan, western France

“…Intersecondary veins branch exmedially. They correspond to Eucalyptolaurus depreii, also described from the AlbianCenomanian of Charente-Maritime (Coiffard et al, 2009). Elliptic to obovate nanophylls show eccentric peltate attachment from which arises one medial primary vein and lateral veins that dichotomize several times before merging into an intramarginal vein (Fig.…”

Rise to dominance of angiosperm pioneers in European Cretaceous environments

“…In the back swamps, they replaced Cycadales and, to a lesser extent, matoniaceous and dicksoniaceous ferns. In the coastal swamps, they competed with matoniaceous ferns (e.g., Weichselia Stiehler) and constitute the earliest record of halophytic angiosperms (28,29). Angiosperms exhibited clear tree habit, especially trees of Lauraceae and Platanaceae, which inhabited disturbed channel margins (Fig.…”

Mecochiridae (Crustacea, Decapoda, Glypheidea) de l’Albien et du Cénomanien de France

“…Ces argiles gris-clair, attribuées à l'unité lithologique A2 sensu Néraudeau et al (1997), sont riches en végétaux (Gomez et al, 2004 ;Coiffard et al, 2009), présentent quelques empreintes d'insectes (Nel et al, 2008), de brachiopodes (Lingula sp. ), de restes de vertébrés (e.g.…”

“…Au sein des argiles feuilletées, deux niveaux à plantes, P1 et P2, de l'unité A2sm sensu Néraudeau et al (2005, fig. 2.2), sont particulièrement riches en empreintes foliaires d'angiospermes (Coiffard et al, 2009), de gymnospermes et de pté-ridophytes, bien que très pauvres en cuticules végétales. C'est le niveau P1 qui a livré les fossiles de crustacés décapodes décrits ici, en association avec les empreintes de plantes et de rares animaux (insectes, lingules, vertébrés).…”