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Full-Text Articles in Life Sciences
Systematics And Biogeography Of The Didymopanax Group Of Schefflera (Araliaceae), Pedro Fiaschi
Systematics And Biogeography Of The Didymopanax Group Of Schefflera (Araliaceae), Pedro Fiaschi
Theses and Dissertations
Schefflera is the largest genus in the angiosperm family Araliaceae, with about 900 species, of which c. 300 belong to five subgeneric groups in the Neotropical region. Previous phylogenetic studies of Schefflera have been limited to a small number of species from this region, and very little is know about phylogenetic relationships in the Brazilian-centered Didymopanax group of this genus. Therefore, to gain a better understanding of the diversity and evolution of the Didymopanax group of Schefflera, I investigated the systematics of these plants in the broader context of the entire Neotropical clade. The main goals were (1) to investigate …
Revision Of The Ant Genus Procryptocerus (Hymenoptera: Formicidae: Myrmicinae: Cephalotini), Francisco Serna
Revision Of The Ant Genus Procryptocerus (Hymenoptera: Formicidae: Myrmicinae: Cephalotini), Francisco Serna
Open Access Theses & Dissertations
Ants of the genus Procryptocerus (Hymenoptera: Formicidae) are characterized by the protrusion of the clypeus forming a broad nasus and antennal scrobes over the eyes. The toruli are located directly posterior to the flanks of the nasus opposite to each other. The vertex is deflexed in most species. I present an in-group comparison of the external morphology focusing on the workers. I also present a general morphology for gynes and males. I analize previously mentioned characters as well as new ones, and clarify their character states in different species. For the metasoma I propose a new system of ant metasomal …
Molecular Systematics And Phylogeography Of The Genus Richardsonius, Derek Dee Houston
Molecular Systematics And Phylogeography Of The Genus Richardsonius, Derek Dee Houston
UNLV Theses, Dissertations, Professional Papers, and Capstones
The complex geological and climatic events that significantly altered the landscape throughout the Cenozoic Era impacted the diversification of many North American taxa, including freshwater fishes. Here, I employ an array of phylogenetic analyses using a multiple gene tree approach to address several questions regarding the phylogenetic relationships of the North American cyprinid genus Richardsonius and two other closely related genera, Clinostomus and Iotichthys. I also use divergence time estimates generated using fossil calibrations to qualitatively assess the phylogeographic implications of evolution within and among these three genera. Mitochondrial and nuclear DNA sequences show a sister relationship between Iotichthys and …