First evidence of fossil Cryosophileae (Arecaceae) outside the Americas (early Oligocene and late Miocene of France): Anatomy, palaeobiogeography and evolutionary implications
- 作者：Romain Thomas ; thomas@mnhn.fr ; Dario De Franceschi
- 关键词：Coryphoideae ; Coccothrinax ; Miocene ; Oligocene ; Palmoxylon ; Palm stem anatomy
- 刊名：Review of Palaeobotany and Palynology
- 出版年：2012
- 期刊代码：80_00346667
- 类别：ear
- 出版时间：1 February, 2012
- 卷：171
- 期：Complete
- 页码：27-39
- 文件大小：4742 K
摘要
A recent anatomical study of living palm stems shows that the five palm subfamilies and their tribes have useful identification characters. This study intends to show that identification of fossil palm stems from anatomical descriptors is potentially possible at the tribe level. As a concrete application, we study the holotype of Palmoxylon vestitum (Saporta) Stenzel and some other stems of two localities: five fossil palm stems from the lower Oligocene of Apt (Vaucluse, France) and two from the upper Miocene of Castellane (Alpes-de-Haute-Provence, France). These seven palm stems belong to the same species (P. vestitum). With a referential of living stems, we improve the identification of this species within the palm family. This species is a Cryosophileae (Coryphoideae) and the closer living genus is Coccothrinax Sargent This discovery has important consequences on the history of the palm family. Indeed, it is the first record of this tribe outside the Americas. Currently the living Cryosophileae are mainly restricted to Central America and this identification provides evidence for a Laurasian origin of this tribe, during the early Eocene as for its sister tribe (Sabaleae). Furthermore, the ecology of this tribe and of this genus gives more information about the palaeoclimatical conditions of these two localities (dry area to subtropical dry forest).