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.

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Fossil conifers from the Early Cretaceous, most likely late Aptian, Crato Formation were studied. The excellent preservation of several of those fossils allowed detailed investigations of the leaf epidermis by light microscope (LM) and by scanning electron microscope (SEM). Members of two conifer taxa were recognized: The Araucariaceae are represented by a female cone of cf. Aruucuriu spec. A juvenile cone (Araucuriostrobus spec.) and sterile foliage shoots of Brachyphyllum obesuni might be attributed to the Araucariaceae as well. The morpho-genus Lindleycludus (incertae sedis) is represented by foliage shoots. The occurrence of Lzndleycludus is the first record of this extinct morpho-genus in the Southern Hemisphere. Anatomical features of these conifers are interpreted as adaptations to a warm seasonally dry climate. Taphonomic problems concerning these conifer remains are discussed. ZusammenfassungFossile Koniferen aus der unterkretazischen, hochstwahrscheinlich oberaptischen Crato Formation wurden untersucht. Die ausgezeichnete Erhaltung einiger Exemplare gestattete die Analyse von Blattepidermen mittels Licht-und Rasterelektronenmikroskop. Vertreter zweier Koniferentaxa wurden nachgewiesen: Araucariaceae kommen mit einem weiblichen Zapfen von cf. Araucuriu spec. vor. Ein juveniler Zapfen (Araucuriostrobus spec.) und sterile Zweige mit der Beblatterung der Morpho-Species Brachyphyllum obesum werden unter Vorbehalt ebenfalls zu den Araucariaceae gestellt. Vegetative Organe der Morpho-Gattung Lindleycludus (incertae sedis) sind ebenfalls erhalten. Das Vorkommen von Lindleycludus ist ein erster Nachweis dieser fossilen Morpho-Gattung in der Sudhemisphare. Anatomische Merkmale dieser Koniferen werden als Anpassungen an ein warmes, saisonal trockenes Klima gedeutet. Im Zusammenhang mit den Koniferenresten werden taphonomische Probleme diskutiert.

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Morphology and anatomy of a fossil monocotyledon from the late Early Cretaceous and extant monocots are compared. Anatomy was examined based on publications, while leaf morphology, especially the venation, required new observations on fresh and herbarium material. Spixiarum kipea gen. et sp. nov. belongs most likely to Araceae, and may be sister to Orontioideae or is even part of this tribe. Consequently, proto‐Araceae were most likely present during the Early Cretaceous in South America. The occurrence of Spixiarum in South America indicates a north Gondwana origin for Orontioideae and and thus may indicate a Gondwanan origin for proto‐Araceae. Sedimentological and taphonomic context indicate that Spixiarum had probably a helophytic ecology similar to living Orontioideae and formed possibly the aquatic vegetation of the Crato Lake in association with the Nymphaeales Pluricarpellatia peltata and Jaguariba wiersemana. Early Cretaceous monocotyledon remains have been rarely recorded. It is debatable if their scarceness is a sign of low diversity or may be due to taphonomic/ecologic reasons.

A fossil herbaceous angiosperm, Pluricarpellatia peltata gen. et sp. nov., is described from the Lower Cretaceous Crato Formation of northeastern Brazil. The description is based on several nearly complete specimens with roots, cordate, excentrically peltate to centrally peltate leaves, and flowering structures with in situ seeds. The seeds are smooth to verrucate and have the micropyle and hilum close together and have laminar placentation. Pluricarpellatia shares several characters with extant Nymphaeales, such as a rhizomatous growth form and simple, petiolate, peltate leaves, and laminar placentation. Similarities to Cabombaceae include an apocarpous gynoecium. However, the carpel morphology clearly differs from extant Cabombaceae so that Pluricarpellatia is considered to represent an extinct member of Nymphaeales, most likely branching off early in this lineage, and may thus be the most basal member of this clade described so far. In addition to Pluricarpellatia an unnamed nymphaealean plant (Taxon A), possibly belonging to the Nymphaeaceae, is described. During the late Aptian to earliest Albian representatives of Nymphaeales may have already developed a moderate diversity.

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