I. Poole et al., A fossil wood flora from King George Island: Ecological implications for an Antarctic Eocene vegetation, ANN BOTANY, 88(1), 2001, pp. 33-54
Early Tertiary sediments of the Antarctic Peninsula region continue to yiel
d a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood
. The wood flora under consideration is from the Collins Glacier region on
Fildes Peninsula. King George Island and is derived from tuffaceous sedimen
ts of the Middle Unit of the Fildes Formation, These deposits accumulated i
n a volcanic setting adjacent to a basic-intermediate stratocone. The fossi
l assemblage provides further evidence for the existence of cool temperate
forests similar in composition to those found today in New Zealand, Austral
ia and, in particular. southern South America, This paper describes two con
ifer and five angiosperm morphotypes. four of which are new additions to th
e Antarctica palaeoflora records. Cupressinoxylon Goeppert, which is the do
minant conifer in terms of numbers, and Podocarpoxylon Gothan represent the
conifers. The angiosperm component includes two species of Nothofagoxylon
and two previously undescribed wood morphotypes that exhibit greatest anato
mical similarity to woods of Luma A. Gray. (Myrtaceae) and Eucryphia Cav. (
Cunoniaceae). These morphotypes are described and assigned to the organ gen
eral Myrceugenelloxylon Nishida, and Weinmannioxylon Petriella, respectivel
y. A model based on the extant cool temperate Valdivian rainforests is prop
osed and ecological reconstructions based on palaeobotanical and geological
evidence suggest that changes in the palaeovegetation reflect natural dyna
mics following volcanic disturbances. (C) 2001 Annals of Botany Company.