Trigonia thoracica Mollusk Fossil

 

The fossil for today's posting is Tennessee's state fossil (I think, the genus name is slightly different). This bivalve mollusk is called Trigonia thoracica (Morton, 1834). It existed in the Cretaceous Period (144-65 million years ago). The fossil was found in the Tennessee USA.

The fossil was on display in the Evolving Planet section of The Field Museum of Natural History in Chicago Illinois, USA as of August 2020. Accession number is PE9161.

The genus named by Bruguière in 1789.

Source:

U.S. Geological Survey Professional Paper 137, The Fauna of the Ripley Formation on Coon Creek, Tennessee by Bruce Wade, 1926.

https://www.google.com/books/edition/Professional_Paper/G8NRAQAAMAAJ?hl=en&gbpv=1&dq=trigonia%20thoracica&pg=PP9&printsec=frontcover

Acer Maple Leaf Fossils

 

Oh, Canada. Today's post is Canada's national symbol showing pictures of  maple leaves plant fossils called Acer sp. (Linnaeus). These plant fossils date to the Oligocene Epoch (33.7-23.8 million years ago). They were found in the state of Oregon, USA. 

The fossils were on display in the Evolving Planet section of The Field Museum of Natural History in Chicago Illinois, USA as of August 2020. 

These fossils were only identified by their genus name. The name Acer is attributed to Carolus Linnaeus (1707-1778) the Swedish botanist and "father of taxonomy" who used the common Latin name for maple trees. The name was derived from Indo-European origins meaning "sharp". I believe he named it in Systema Naturae 1758 part 8.

References:

https://www.fnps.org/assets/pdf/palmetto/v13i4p8austin.pdf

https://ebrary.net/27999/environment/maple

https://earthlingnature.wordpress.com/2018/07/30/the-history-of-systematics-plants-in-systema-naturae-1758-part-8/

Quercus berryi Leaf Fossil

Above is a picture of an oak leaf plant fossil called Quercus berryi (Trelease, 1918). This plant fossil dates to the Oligocene Epoch (33.7-23.8 million years ago). It was found in the state of Oregon, USA. While not listed on the label, this might be from the John Day Basin.

The fossil was on display in the Evolving Planet section of The Field Museum of Natural History in Chicago Illinois, USA as of August 2020. Accession number is UP525. It is part of a plant leaf fossil collection on display.

Renamed by William Trelease (1857-1945) in 1918. The Ancient Oaks of America. Memoirs of the Brooklyn Botanical Garden 1: 492–501. It looks to me he changed the name of Q. breweri Lesquereux 1883 not Wats. to Q. berryi n. nom.