''Mesosingeria'' is a genus of fossil foliage attributable to the

Cycadales Cycads are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or ...

. This genus is found in Early Cretaceous rocks from Argentina.

Taxonomy

The genus was erected by Sergio Archangelsky based on material from the Anfiteratro de Ticó Formation in

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

to include two species, namely ''M.coriacea'' and ''M. herbstii''. The name of the genus is dedicated to the

mycologist Mycology is the branch of biology concerned with the study of fungus, fungi, including their genetics, genetic and biochemistry, biochemical properties, their Taxonomy (biology), taxonomy and ethnomycology, their use to humans, including as a so ...

Rolf Singer Rolf Singer (June 23, 1906 – January 18, 1994) was a Germany, German-born mycologist and one of the most important Taxonomy (biology), taxonomists of gilled mushrooms (agarics) in the 20th century. After receiving his Ph.D. at the University ...

. Other five species were later added to the genus from the same localities.

Description

The genus includes foliage fossils of bipinnate leaves with a flat rachis. The pinnules are oblong to lanceolate, alternate, with one or more veins entering each pinnule, then dichotomizing and continuing straight to the apex. The cuticle presents monocyclic stomata which are usually sunken in a stomatal pit constricted by a ring of cuticle on the outside.

References

Cycads Prehistoric gymnosperm genera {{cretaceous-plant-stub