Welwitschiaceae from the Lower Cretaceous of northeastern Brazil.

Abstract:

:Welwitschiaceae, a family in the Gnetales, is known today from only one extant species, Welwitschia mirabilis. This species is distributed in the Namibian desert, along the western coast of southern Africa, about 10 km inland from the coast. Very little is known about the fossil record of this family. Lower Cretaceous megafossils of various organs, assigned to Welwitschiaceae, are presented here. These fossils include young stems with paired cotyledons attached (Welwitschiella austroamericana n. gen. et sp.), isolated leaves (Welwitschiophyllum brasiliense n. gen. et sp.), and axes bearing male cones (Welwitschiostrobus murili n. gen. et sp.). They were collected in the Crato Formation, which is dated by palynomorphs and ostracods as Late Aptian (114 to 112 million years ago). These sediments are exposed in the Araripe Basin of northeastern Brazil. This study brings together new information of the megafossil record of Welwitschia-like plants and also reports of pollen said to be similar to that of Welwitschia from Lower Cretaceous sediments.

journal_name

Am J Bot

authors

Dilcher DL,Bernardes-De-Oliveira ME,Pons D,Lott TA

doi

10.3732/ajb.92.8.1294

subject

Has Abstract

pub_date

2005-08-01 00:00:00

pages

1294-310

issue

8

eissn

0002-9122

issn

1537-2197

pii

92/8/1294

journal_volume

92

pub_type

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