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Itea is a genus of about 20 species of trees and shrubs that are today native to southeastern North America, eastern Asia, and eastern Africa. In this paper, I review the fossil record of Itea, which is based on four types of fossils: diporate, psilate pollen attributed to Itea or the dispersed pollen genus Iteapollis; carpofossils representing fruits and seeds attributed to Itea europaea; flowers preserved in amber and assigned to Adenanthemum iteoides; and leaf impressions attributed to Itea. The distributions of these fossils indicate that Itea was present in western North America from the early Eocene to Miocene, in eastern North America beginning no later than the early Miocene, and in western Eurasia from the late Eocene to Pliocene. Only one datapoint is known from eastern Asia; it is early Miocene in age. Based on the fossil record, it can be inferred that Itea crossed between continents over both the Bering Land Bridge and North American Land Bridge, and that it reached Africa from Europe via Anatolia. Thus, it is predicted that the sole extant North American species, I. virginica, may be most closely related to the sole extant African species, I. rhamnoides. The potential application of Itea fossils to calibrating phylogenetic trees generated from molecular sequence data is also discussed. [ABSTRACT FROM AUTHOR]

The article offers information on the description of a Miocene fossil crane fly Tipula nevadensis from a single male that is preserved in fine paper shale from Stewart Valley, Nevada. It states that Tipula nevadensis is a new species that is noted from other similar tertiary crane flies in western North America. It also mentions that the head of the species is rounded and narrowed behind compound eyes, and its total body length measures 15.8 millimeter (mm) with 18.3 mm wing length.

Fin-winged fruits have two or more wings aligned with the longitudinal axis like the feathers of an arrow, as exemplified by Combretum, Halesia, and Ptelea. Such fruits vary in dispersal mode from those in which the fruit itself is the ultimate disseminule, to schizocarps dispersing two or more mericarps, to capsules releasing multiple seeds. At least 45 families and more than 140 genera are known to possess fin-winged fruits. We present an inventory of these taxa and describe their morphological characters as an aid for the identification and phylogenetic assessment of fossil and extant genera. Such fruits are most prevalent among Eudicots, but occur occasionally in Magnoliids (Hernandiaceae: Illigera) and Monocots ( Burmannia, Dioscorea, Herreria). Although convergent in general form, fin-winged fruits of different genera can be distinguished by details of the wing number, texture, shape and venation, along with characters of persistent floral parts and dehiscence mode. Families having genera with fin-winged fruits and epigynous perianth include Aizoaceae, Apiaceae, Araliaceae, Asteraceae, Begoniaceae, Burmanniaceae, Combretaceae, Cucurbitaceae, Dioscoreaceae, Haloragaceae, Lecythidiaceae, Lophopyxidaceae, Loranthaceae, and Styracaceae. Families with genera having fin-winged fruits and hypogynous perianth include Achariaceae, Brassicaceae, Burseraceae, Celastraceae, Cunoniaceae, Cyrillaceae, Fabaceae, Malvaceae, Melianthaceae, Nyctaginaceae, Pedaliaceae, Polygalaceae, Phyllanthaceae, Polygonaceae, Rhamnaceae, Salicaceae sl, Sapindaceae, Simaroubaceae, Trigoniaceae, and Zygophyllaceae. This survey has facilitated the identification of fossil winged fruits such as Combretaceae and Araliaceae in the late Cretaceous of western North America and provides additional evidence toward the identification of various Cenozoic fossils including Brassicaceae, Fabaceae, Polygonaceae, Rutaceae, and Sapindaceae. [ABSTRACT FROM AUTHOR]

A new genus is described based on fossilized winged fruits from former lake deposits of Wyoming, Utah, Colorado, Oregon, and British Columbia, ranging in age from latest Paleocene to early Middle Eocene. Lagokarpos lacustris McMurran et Manchester gen. et sp. nov. fruits have an elliptical to globose seed body and a conspicuous pair of apical wings with pinnate venation. These wind-dispersed fruits are compared with and distinguished from similar extant winged fruits such as Dipterocarpus Gaertn f. (Dipterocarpaceae), Gyrocarpus Jacq. (Hernandiaceae), and Alberta E. Meyer (Rubiaceae).Nomodern fruit was found to exhibit the combination of characters seen in Lagokarpos, and we conclude that it represents an extinct genus of as yet unknown familial affinity. [ABSTRACT FROM AUTHOR]

It has been proposed that extensive wildfires occurred after the Cretaceous-Tertiary (K-I) impact event. An abundance of soot and pyrosynthetic polycyclic aromatic hydrocarbons (pPAH5) in marine K-T boundary impact rocks (BIRs) have been considered support for this hypothesis. However, nonmarine K-T BIRs, from across North America. contain only rare occurrences of charcoal yet abundant noncharred plant remains. pPAH5 and soot can be formed from a variety of sources, including partial combustion of vegetation and hydrocarbons whereby modern pPAH signatures are traceable to their source. We present results from multiple nonmarine K-T boundary sites from North America and reveal that the K-T BIRs have a pPAH signature consistent with the combustion of hydrocarbons and not living plant biomass. providing further evidence against K-T wildfires and compelling evidence that a significant volume of hydrocarbons was combusted during the K-T impact event. [ABSTRACT FROM AUTHOR]

Exposures across the Cretaceous–Tertiary (K–T) and Eocene–Oligocene (E–O) boundaries, in Texas and Mississippi, respectively, probably represent the most complete and best-preserved fossil molluscan sequences across these boundary intervals in the world. Outcrops from both boundaries contain pristine aragonitic and calcitic molluscan shells, which were deposited in fine-grained sediments from open marine environments. The K–T and the E–O extinctions exhibit very different recovery patterns, probably reflecting very different causes as well as magnitudes of extinction.The K–T sequence contains a molluscan fossil record that is consistent with an abrupt extinction event at the K–T boundary and a prolonged initial recovery in hostile oceanographic conditions. The uppermost 10 m of Upper Cretaceous sediments contain a diverse (approximately 40 species) molluscan fauna dominated by suspension feeders. The earliest Paleocene sediments immediately above the tsunami bed contain an impoverished fauna dominated by deposit feeders. The Paleocene fauna slowly climbs in diversity but remains relatively impoverished and dominated by deposit feeders for several hundred thousand years after the extinction in conjunction with anomalous δ13C values that suggest prolonged suppression of marine primary productivity. Diverse suspension-feeder dominated molluscan assemblages reappear with the resumption of normal conditions of primary production. In the long term, early to middle Paleocene gamma diversity includes evolutionary “bloom taxa,” families that exhibit unusual speciation bursts that subside in the Eocene. Total diversity for the Gulf Coast does not approach Cretaceous levels until the Late Eocene representing a total recovery interval of nearly 25 million years.While the E–O event also reflects a molluscan extinction rate of over 90% in the Gulf of Mexico, there are no signs of hostile environmental conditions in the recovery fauna. Early Oligocene molluscan assemblages are diverse and dominated by suspension feeders characteristic of normal marine conditions. The hiatus at the E–O boundary, however, could have obscured a short-term recovery fauna. There is also no sign of long-term perturbation by the E–O extinction. There are no bloom taxa and gamma diversity approaches pre-extinction levels within a few million years. The overall pattern of the E–O extinction is consistent with extinction (and/or migration) associated with long-term cooling. [Copyright &y& Elsevier]

Two new species of the diatom genus Cyclostephanos Round are described from Pliocene fossil deposits in western North America. Cyclostephanos undatus is distinguished from other Cyclostephanos species by its tangentially undulate valve face; Cyclostephanos fenestratus is distinguished by its extremely shallow alveoli. This paper records previously unreported morphological detail of Cyclostephanos and speculates that structure of the puncture, labiate process and strutted process ma), enhance diagnosis of the freshwater genera of the Thalassiosiraceae Lebour emend. Hasle. Cyclostephanos undatus is similar to several Cyclotella species, but its external costae are raised and its alveolar morphology is similar to that of Cyclostephanos dubius (Fricke) Round. Cyclostephanos fenestratus is similar in external view to Stephanodiscus Ehrenb. However the two species described here have flat cribra covering the mantle puncta and the labiate processes appear to lack external tubes, whereas Stephanodiscus species have domed mantle cribra and external tubes. [ABSTRACT FROM AUTHOR]