Ettingshausenia louravetlanica (Herman et Shczepetov) Herman et Moiseeva  

 

 

Locality

Grebenka, Yelisseev Locality, Site 3PL

Locality Map

Geological Map

Sedimentary Log

 

Description

The following is taken from Moiseeva (2010).

The leaves are simple, entire margined, with small lateral lobes or without lobes, medium and large in size. The leaf blade is often asymmetrical, of variable outlines: oval, oval–ovate, broadly rhomboidal, or obovate. The petiole is long, more than 7 cm in length. The leaf base is broadly or narrowly cuneate and decurrent. The apices of the central and lateral lobes are acute or obtuse. The lateral lobes are lacking or small, triangular, often are situated at different height, and differ in size. The leaf margin is dentate-emarginate, with small glands terminating the teeth. The venation is palmate-pinnate and craspedodromous. The basal veins often come from the midrib asymmetrically; they are alternating or, more rarely, opposite, situated at a distance of 5–25 mm from the leaf base. The basal veins are nearly as thick as other secondary veins and have one or two acroscopic and five to seven basiscopic deviations. There are up to four infrabasal veins, developed in various degree. The tertiary venation varies from orthogonal-reticulate to branchy scalariform.

The species resembles the type species E. cuneifolia (Bronn) Stiehle from the Cenomanian of Czech Republic (Peruc-Korycany Formation) by the rhomboidal leaf blade, small lateral lobes, and finely dentate leaf margin (Kvacek and Váchová, 2006). E. louravetlanica differs from this species, as well as from the majority of other species of the genus, by the asymmetrical leaf base and leaf blade: arrangement and size of lateral lobes and asymmetrical (alternating) deviation of basal veins. Moreover, the above described leaves of E. louravetlanica are distinctive by their tertiary venation, which is a combination of orthogonal-reticulate and branchy-scalariform types, contrasting to the majority of other species characterized by branchy-scalariform tertiary venation.

Remarks

A detailed description of this species, analysis of its variability, and comparison with similar leaves of the genus Platanus was made by Herman (1994). These leaves were found associating with Anadyricarpa altingiosimila, pistillate heads of the hamamelidaceous morphology (Maslova and Herman, 2004). The necessity to correct the generic name was shown by Maslova and Herman (2004).

This photograph was made in the field. The specimen is in the collection of the Geological Institute, Russian Academy of Sciences, Moscow, Russia. For further details of the context of the collection see Spicer et al. (2002).