''Carya washingtonensis'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

hickory Hickory is a common name for trees composing the genus ''Carya'', which includes 19 species accepted by ''Plants of the World Online''. Seven species are native to southeast Asia in China, Indochina, and northeastern India (Assam), and twelve ...

nut in the

walnut A walnut is the edible seed of any tree of the genus '' Juglans'' (family Juglandaceae), particularly the Persian or English walnut, '' Juglans regia''. They are accessory fruit because the outer covering of the fruit is technically an i ...

family

Juglandaceae The Juglandaceae are a plant family known as the walnut family. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia. The nine or ten genera in the family have ...

. The species is solely known from the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

sediments exposed in Kittitas County near

Ellensburg, Washington Ellensburg is a city in and the county seat of Kittitas County, Washington, United States. It is located just east of the Cascade Range near the junction of Interstate 90 in Washington, Interstate 90 and Interstate 82. The population was 18,666 ...

Type locality

The species was described from the three nut specimens, all found at the no-longer-accessible Badger Pocket-Squaw Creek locality south of Ellensburg, which is now part of the Yakima Training Center. This locality is thought to be an extension of the Ginkgo Flow basalts, notable for the fossils found at Ginkgo Petrified Forest State Park. The Ginkgo Flow, part of the Wanapum basalts is the oldest segment of the Frenchman Springs Member, dating to around 15.6 million years old, or the Langhian stage of the

.Miocene Woods Of Eastern Washington
Accessed 23 May 2011 The nuts were originally discovered as a single silicified,

opal Opal is a hydrated amorphous form of silicon dioxide, silica (SiO2·''n''H2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous (chemical) physical structure, it is classified as a ...

ized mass of well over fifty nuts found in a petrified ''

Platanus ''Platanus'' ( ) is a genus consisting of a small number of tree species native to the Northern Hemisphere. They are the sole living members of the family Platanaceae. All mature members of ''Platanus'' are tall, reaching in height. The type ...

'' stump. The mass was discovered in the 1940s by Carl Clinesmith but as of 1987 the mass was lost and Steven Manchester presumed it was disaggregated with the individual nuts disseminated to various collections. However it is reported in a 1995 '' Washington Geology'' article by

Wesley Wehr Wesley Conrad Wehr (April 17, 1929 – April 12, 2004) was an American paleontology, paleontologist and artist best known for his studies of Cenozoic paleobotany, fossil floras in western North America, the Stonerose Interpretive Center, and as ...

the specimen was, at that time, on display at the Burke Museum of Natural History and Culture, part of the

University of Washington The University of Washington (UW and informally U-Dub or U Dub) is a public research university in Seattle, Washington, United States. Founded in 1861, the University of Washington is one of the oldest universities on the West Coast of the Uni ...

Seattle, Washington Seattle ( ) is the List of municipalities in Washington, most populous city in the U.S. state of Washington (state), Washington and in the Pacific Northwest region of North America. With a population of 780,995 in 2024, it is the List of Unit ...

, USA. At least a portion of the mass is still preserved in the collections at the Burke Museum as specimen number "UWBM38700".

History and classification

''Carya washingtonensis'' was described from three

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

s, the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

, number "HU60073A", and two

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype (biology), isotype ...

s, numbers "HU60073B" and "IU5343". Both the holotype and one paratype are preserved in the paleobotanical collections housed at the Harvard University Biology Laboratories. The second paratype is deposited in the paleobotanical collections in the Indiana university, Department of Geology. The specimens were studied by paleobotanist Steven R. Manchester, currently of the Florida State University Department of Geology as part of his PhD dissertation and was accepted for publication in 1984. Steven Manchester published his 1987 type description for ''C. washingtonensis'' in the journal '' Monographs in Systematic Botany''. The chosen specific name ''washingtonensis'', in reference to

Washington state Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington ...

where only known specimens of the species have been recovered.

Description

The nuts of ''Carya washingtonensis'' are globose in shape, with a smooth to slightly wrinkled surface. They show four faintly developed angles at the apex. The nuts range in size but are all within in length and in width. While the preservation quality varies, the silicification in a number of the specimens was enough to allow examination of the internal anatomy. In general the nut wall and septa are approximately thick without and do not have lacunae but do possess a secondary septum. The

locule A locule (: locules) or loculus (; : loculi) is a small cavity or compartment within an organ or part of an organism (animal, plant, or fungus). In angiosperms (flowering plants), the term ''locule'' usually refers to a chamber within an ovary ...

is divided into four compartments basally with inner ribs that are well developed and containing vascular bundles and the placentary bundles of primary

septum In biology, a septum (Latin language, Latin for ''something that encloses''; septa) is a wall, dividing a Body cavity, cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Hum ...

arch out peripherally. When described by Steven Manchester, the mass was interpreted to represent a Miocene rodent nut cache and was the oldest known at that time. Since then a slightly older cache was discovered in Germany. The German cache of ''

Castanopsis ''Castanopsis'', commonly called chinquapin or chinkapin, is a genus of evergreen trees belonging to the beech family, Fagaceae. The genus contains about 140 species, which are today restricted to tropical and subtropical eastern Asia. The Engli ...

'' fruits was found in a preserved

sand dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

dating to the Burdigalian stage of the Miocene, making it slightly older than the ''Carya washingtonensis'' cache.

References

{{Taxonbar, from=Q5047672 washingtonensis Prehistoric angiosperms Plants described in 1987 Miocene plants Trees of Northern America Extinct flora of North America Fossil taxa described in 1987