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| image = Dillhoffia cachensis SR 92-17-20 1.jpg | image_caption = Fossil ''Dillhoffia cachensis'' calyces | regnum = Plantae | divisio = Angiospermae | classis = ''incertae sedis'' | familia = ''incertae sedis'' | genus = †''Dillhoffia'' | species = ''D. cachensis'' | binomial = ''Dillhoffia cachensis'' | binomial_authority = Manchester & Pigg, 2008 }} ''Dillhoffia'' is an extinct monotypic genus of flowering plant with a single species, ''Dillhoffia cachensis'' known from Ypresian age Eocene fossils found in British Columbia, Canada, and Washington, USA. The genus and species were described from fifteen specimens found in an unnamed formation belonging to the Kamloops group shales; and two specimens from the Klondike Mountain Formation.〔 The unnamed formation outcrops at the McAbee Fossil Beds near Cache Creek, BC, which is designated the type locality while the two U.S. specimens were recovered from the Tom Thumb Tuff member of the Klondike Mountain Formation in Republic, Washington.〔 It is of interest to note that of the Okanagan highlands fossil sites ''Dillhoffia'' is only known from two locations, and is absent or has not been identified from the others.〔 The holotype specimen, number ''TMP 83.39.175'', is preserved in the Royal Tyrell Museum and the paratype specimens are in the Thompson Rivers University and University of Saskatchewan collections.〔 The specimens were studied by paleobotanists Steven Manchester of the University of Florida and Kathleen Pigg of Arizona State University. Manchester and Pigg published the 2008 type description for ''D. cachensis'' in the journal ''Botany'', Volume 86, number 9.〔 They chose the generic name ''Dillhoffia'' to honor the brothers Richard M. Dillhoff and Thomas A. Dillhoff for their substantial contributions and promotion of Pacific Northwest North American Paleogene floras.〔 The specific name is a reference to Cache Creek, British Columbia, the nearest town to the McAbee site.〔 ''Dillhoffia'' is known from infructescences only.〔 The infructescences are pedunculate having a globose head which bore at least twelve flowers and has been preserved as fossils with several sessile fruits. The fruits are elongate to ellipsoidal in form, being by , and indehiscent.〔 The enlarged calyx present on the fruits is thought to have been used for wind transport, with the calyx being dish to funnel shaped and born approximately three-quarters of the way up the fruit from the base. Formed from a persistent paranth, the calyx may have been accrescent, as small-sized calyces are known.〔 It is unknown what the petals and stamens looked like, as none have been found, possibly being shed during fruit formation. ''Dillhoffia'' was most likely a non-magnoliid angiosperm as indicated by is inferior ovary, but placement into a specific family is not possible with the fossils known.〔 ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dillhoffia」の詳細全文を読む スポンサード リンク
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