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Title: Early Eocene infructescences from Argentine Patagonia expand the biogeography of Malvoideae
Abstract PremiseFossil infructescences and isolated fruits with characters of Malvoideae, a subfamily of Malvaceae (mallow family), were collected from early Eocene sediments in Chubut, Argentina. The main goals of this research are to describe and place these fossils systematically, and to explore their biogeographical implications. MethodsFossils were collected at the Laguna del Hunco site, Huitrera Formation, Chubut, Patagonia, Argentina. They were prepared, photographed, and compared with extant and fossil infructescences and fruits of various families using herbarium material and literature. ResultsThe infructescences are panicles with alternate arrangement of fruits. They bear the fruits on short pedicels that are subtended by a bract; the fruits display an infracarpelar disk and split to the base into five ovate sections interpreted as mericarps. Each mericarp is characterized by an acute apex and the presence of a longitudinal ridge. The isolated fruits show the same features as those on the infructescences. The fossils share unique features with members of the cosmopolitan family Malvaceae, subfamily Malvoideae. ConclusionsThe fossils have a unique combination of characters that does not conform to any previously described genus, justifying the erection of a new genus and species,Uiher karuen. This new taxon constitutes the first known Malvoideae reproductive fossils of the Southern Hemisphere, expanding the distribution of Malvoideae during the early Eocene.  more » « less
Award ID(s):
1925755 1556666 1925552
PAR ID:
10589829
Author(s) / Creator(s):
; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
American Journal of Botany
Volume:
111
Issue:
9
ISSN:
0002-9122
Page Range / eLocation ID:
e16384
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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