School of Life Sciences, Box 874501, Arizona State University, Tempe, Arizona 85287-4501 USA.
Am J Bot. 2008 Jul;95(7):824-32. doi: 10.3732/ajb.2007340.
The Icacinaceae occur pantropically today, but are well represented by fossil fruits of the warm Early Middle Eocene, when tropical plants that currently occupy low latitudes were more widely distributed in higher latitudes. Members of this family are first known in the Late Cretaceous; however, fossil fruits of tribe Iodeae are quite rare before the Eocene. In this paper we describe the first formally recognized Late Paleocene icacinaceous taxa from western North America. We name two new species of Icacinicarya based on anatomically preserved fruits and establish a new genus, Icacinicaryites, for impressions with a strong similarity to Icacinicarya that lack anatomical preservation. These new records from the Almont/Beicegel Creek flora in North Dakota and several localities in Wyoming, Colorado, and Montana complement records known from the Early Eocene of England and document an increased diversity of Iodeae and related forms in the Paleogene of western North America.
现今，铁青树科植物遍布全球，但在温暖的早中新世化石果实中表现良好，当时目前占据低纬度地区的热带植物在高纬度地区的分布更为广泛。该科成员最早出现在白垩纪晚期；然而，在古近纪之前，Iodeae 族的化石果实相当罕见。本文描述了北美西部首次正式确认的晚古新世铁青树科分类群。我们基于解剖保存的果实命名了两个新的 Icacinicarya 种，并为与 Icacinicarya 具有强烈相似性但缺乏解剖保存的印痕建立了一个新属，即 Icacinicaryites。这些来自北达科他州 Almont/Beicegel Creek 植物群和怀俄明州、科罗拉多州和蒙大拿州的几个地点的新记录补充了已知的来自英格兰早始新世的记录，并记录了西半球古近纪 Iodeae 和相关形式的多样性增加。
