@article{521a2aae2c344b53a8890b59873b1808,
title = "Newly recognized diversity in Trochodendraceae from the Eocene of Western North America",
abstract = "The Eocene flora of the Okanogan Highlands in the Pacific Northwest of North America has been recognized previously to include extinct species of both extant genera of the Trochodendraceae. Here, using microcomputed tomography (μCT) scanning to augment traditional methods, we recognize additional diversity, including two new fruit types. Concavistylon wehrii sp. nov. is documented by a fertile twig with attached leaves and an infructescence, allowing for an unusually complete reconstruction of this extinct genus. Concavistyon wehrii infructescences are racemes bearing fruits on short pedicels. Fruits are apically dehiscent capsules with four to six styles. The leaves resemble those of modern Trochodendron in pinnate venation, glandular teeth, and epidermal anatomy but have short petioles. The second new type of infructescence, Pentacentron sternhartae gen. et sp. nov., resembles extant Tetracentron in having small, sessile, apically dehiscent capsules but consistently has five, rather than four, styles. The μCT X-ray imaging demonstrates that fruits of both Concavistylon and Pentacentron differ from those of extant Trochodendraceae in having styles that are concave with stigmas directed inward rather than outward. These fossils, together with previously recognized fossil fruits and leaves of Trochodendron and leaves of Tetracentron from the same beds, indicate that the Trochodendraceae family was more diverse 50–52 Ma than it is today.",
keywords = "British Columbia, Concavistylon, Fruits, Infructescences, Leaves, McAbee, Republic, Tertiary, Tetracentron, Trochodendron, Washington",
author = "Manchester, {Steven R.} and Kathleen Pigg and Zlatko Kva{\v c}ek and Devore, {Melanie L.} and Dillhoff, {Richard M.}",
note = "Funding Information: Betchley, Jacob Dickson, Zena Johnson, Jean Kammer, B. J. Laird, Shannon Miller, Mamie Mitchell, Bill Schulte, and the Stonerose Interpretive Center staff; Ron Eng and Meredith Rivin provided access to specimens at the Burke Museum of Natural History and Culture, Seattle; Katherine Meade and Travis Wellman provided access to specimens housed in the Stonerose Inter- pretive Center, Republic, Washington. Z. Kva{\v c}ek received support from Charles University through the Progress Q45 project. This work was supported partially by US National Science Foundation grant EAR 1338285. K. B. Pigg{\textquoteright}s travel was supported in part by Jane Maienschein, Center for Biology and Society, School of Life Sciences, Arizona State University. Funding Information: Specimens important to this investigation were donated by Thomas A. Dillhoff, Dave Langevin, Jeremiah Bauknight, Alex Betchley, Jacob Dickson, Zena Johnson, Jean Kammer, B. J. Laird, Shannon Miller, Mamie Mitchell, Bill Schulte, and the Stonerose Interpretive Center staff; Ron Eng and Meredith Rivin provided access to specimens at the Burke Museum of Natural History and Culture, Seattle; Katherine Meade and Travis Wellman provided access to specimens housed in the Stonerose Inter pretive Center, Republic, Washington. Z. Kva{\v c}ek received support from Charles University through the Progress Q45 project. This work was supported partially by US National Science Foundation grant EAR 1338285. K. B. Pigg{\textquoteright}s travel was supported in part by Jane Maienschein, Center for Biology and Society, School of Life Sciences, Arizona State University. Publisher Copyright: {\textcopyright} 2018 by The University of Chicago. All rights reserved.",
year = "2018",
month = oct,
day = "1",
doi = "10.1086/699282",
language = "English (US)",
volume = "179",
pages = "663--676",
journal = "International Journal of Plant Sciences",
issn = "1058-5893",
publisher = "University of Chicago",
number = "8",
}