Zingiberalean fossils from the late Paleocene of North Dakota, USA and their significance to the origin and diversification of Zingiberales

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Description
The Zingiberales, including the gingers (Zingiber), bananas (Musa) and ornamental flowers (Strelitzia, Canna, and Heliconia) are a diverse group of monocots that occupy the tropics and subtropics worldwide. The monophyly of the order is well supported, although relationships between families

The Zingiberales, including the gingers (Zingiber), bananas (Musa) and ornamental flowers (Strelitzia, Canna, and Heliconia) are a diverse group of monocots that occupy the tropics and subtropics worldwide. The monophyly of the order is well supported, although relationships between families are not well resolved. A rapid divergence of the Zingiberales has been proposed to explain the poor resolution of paraphyletic families in the order, and direct fossil evidence shows members of both of these lineages of Zingiberaceae and Musaceae were present by the Late Cretaceous. Comparisons of the fossils with extant relatives and their systematic placement have been limited because variation within modern taxa is not completely known. The current study focuses on describing zingiberalean fossil material from North Dakota that includes seeds, leaves, buds, adventitious roots and rhizomes. A survey of extant zingiberalean seeds was conducted, including descriptions of those for which data were previously unknown, in order to resolve the taxonomic placement of the fossil material. Upon careful examination, anatomical characters of the seed coat in fossil and extant seeds provide the basis for a more accurate taxonomic placement of the fossils and a better understanding of character evolution within the order.
Date Created
2012
Agent

The Phoenix Four Rivers Flora, Maricopa County, Arizona

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Description
ABSTRACT The Phoenix Four Rivers Flora is an inventory of all the vascular plants growing along the Salt, Gila, New and Agua Fria Rivers, and their tributaries in the Phoenix Metropolitan Area during the years of the study (2009-2011).

ABSTRACT The Phoenix Four Rivers Flora is an inventory of all the vascular plants growing along the Salt, Gila, New and Agua Fria Rivers, and their tributaries in the Phoenix Metropolitan Area during the years of the study (2009-2011). This floristic inventory documents the plant species and habitats that exist currently in the project area, which has changed dramatically from previous times. The data gathered by the flora project thus not only documents how the current flora has been altered by urbanization, but also will provide a baseline for future ecological studies. The Phoenix Metropolitan Area is a large urbanized region in the Sonoran Desert of Central Arizona, and its rivers are important for the region for many uses including flood control, waste water management, recreation, and gravel mining. The flora of the rivers and tributaries within the project area is extremely diverse; the heterogeneity of the systems being caused by urbanization, stream modification for flood control, gravel mining, and escaped exotic species. Hydrological changes include increased runoff in some areas because of impermeable surfaces (e.g. paved streets) and decreased runoff in other areas due to flood retention basins. The landscaping trade has introduced exotic plant species that have escaped into urban washes and riparian areas. Many of these have established with native species to form novel plant associations.
Date Created
2011
Agent