Malvaceae Info (Home)
Fossil Index
Fossil material of plants can be difficult to identify as to species, genus, or larger taxonomic units, as usually what is found is individual parts of plants, such as wood, leaves, flowers, fruits or pollen, and these are often insufficient for identification, particularly for older material why is less closely related to modern material, and may be less well preserved. Consequently, and as fossils of one plant part often cannot be unambigiously associated with those of another plant part, palaeobotanists use form genera to classify parts of plants of uncertain taxonomic position. The suffix -phyllum is often used in generic names, indicating a similarity with the leaves of the modern genus whose name is combined with that suffix. It cannot be assumed that the fossil leaves represent a species particularly close to the modern genus.
I suspect that the genera and species of fossil malvaceous leaves listed below are far from an exhaustive coverage. Furthermore fossil leaves may be ascribed to a living genus, and this will be even harder to track down.
Leaf fossils described as Bombacites jacksoniana are recorded from Texas.
Bombacophyllum is a form genus representing fossil leaves similar to those of the genus Bombax (or bombacoids in general). Bombacophyllum argillaceum is recorded from the Upper Cretaceous.
Leaf material ascribed to Brachychiton is reported from the Tertiary of Australia and New Zealand.
Byttneriophyllum is a form genus representing fossil leaves similar to those of the genus Byttneria.
Byttneriophyllum tiliaeofolium is recorded from the Neogene of Slovenia, the Miocene of Poland, and also from East Asia. It has been confused with Dombeyopsis lobata, from which it differs in possessing a strongly asymetrical leaf base. Whether this represents a malvaceous plant is not clear; on the one hand it is associated with malpighiaceous fruit morphospecies Banisteriaecarpum giganteum, on the other hand it has been associated with the pollen morphospecies Intratriporopollenites instructus, which is probably tilioid.
Leaf material ascribed to Cola is recorded from the Late Oligocene of northwestern Ethiopia.
Leaf material assigned to "Fremontia" coriacea and "Fremontia" lobata is found in the Miocene of California. Material referred to the former is also found in the Pliocene (Piru Gorge), and to the latter in the Miocene Kinnick and Pliocene Tasssajero Fms. Material referred to "Fremontia" is also found in Eocene deposits in Yellowstone.
Fossil leaves from the Tertiary of North America and Eurasia (including Greenland and Spitzbergen) have in the past been assigned to various species of Grewia, including Grewia auriculata, Grewia crenata, Grewia crenulata and Grewia obovata; these four species are now all assigned to Trochodendroides crenulata (Cercidiphyllaceae). These should not be confused with living Grewia species with the same names.
Grewia mallotophylla is recorded from the Miocene of Nepal [b]. (This is one of several species described in a paper based on leaf and seed macrofossils; the abstract doesn't indicate on which G. mallotophylla was raised, but the specific name is a strong hint that it is based on leaf material.) Grewia tiliaefolia and Grewia tistaensis are recorded from the Middle Miocene of West Bengal [a].
Other material assigned to Grewia includes
Luehea roxoii Dolianiti is described from a leaf fossil from the Pliocene of Minas Gerais in Brasil.
Material assigned to Luehea newberryana (Knowlton) is found in the Early and Middle Eocene of Wyoming. This is now considered to belong to Populus [d].
Malvaciphyllum is a form genus representing fossil leaves similar to those of living mallows.
Malvaciphyllum quenquiadensis is recorded from the Upper Miocene of Argentina, and fossils assigned to this genus, but to no specific species, from the Pliocene of Brasil.
Plafkeria includes leaf fossils from the Palaeogene of North America and North East Asia, and is considered to be tiliaceous.
Plafkeria obliquifolia is reported from the Late Oligocene of Oregon and the Eocene of California. Plafkeria, unspecified as to species, is recorded from the Lower Eocene of British Columbia.
Plafkeria basiobliqua (Oishi. et Huzioka) Tanai is reported from the Palaeogene of Hokkaido.
Sphaeralcea exhumata is recorded (as Malvastrum exhumatum Cockerell) from the Florissant Formation of Colorado. An image of a leaf is available at the Florissant Fossil Beds National Monument web site.
Leaf fossils assigned to Sterculia are found in Eocene to Oligocene of Europe. A palmate lobed form from Dalmatia and Slovenia is known as Sterculia labrusca.
Tiliaephyllum is a form genus representing fossil leaves similar to those of the genus Tilia. As this form genus is recorded from the Upper Cretaceous, and the fossil record of Tilia extends no earlier than the Palaeocene, it seems to me that these leaves do not belong to Tilia, and may not belong to Malvaceae. (Confusion between fossil TIlia and Populus (Salicaceae) leaves, for example, has occurred.) In particular Tillaephyllum dubium Newberry from the Turonian Raritan Fm is too early to be malvaceous.
Tiliaephyllum tsagajanicum is recorded from Manchuria, Kamchatka, the Amur river region, and northern Alaska. It may be referable to Davidia [c].
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© 2005, 2007 Stewart R. Hinsley