A revision of the genus Neochoroterpes (Ephemeroptera: Leptophlebiidae) : with a discussion of zoogeography /
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1989.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | The three Choroterpes subgenera, Choroterpes s.s., Euthraulus, and Neochoroterpes are elevated to the generic rank. The imagoes and nymphs of each species of Neochoroterpes are associated by laboratory rearing and field studies. Based on these studies, Choroterpes oklahoma Traver and Choroterpes nanita are transferred to Neochoroterpes new combinations. Neochoroterpes mexicanus Allen, the type species of the genus, is synonymized with N. oklahoma (Traver) and N. crocatus Allen is synonymized with N. nanita, new synonymies. The male imagoes and nymphs of N. oklahoma and N. nanita are redescribed. Male imagoes of Neochoroterpes kossi are described for the first time. Neochoroterpes moctezuma, new species, is described from nymphs and male imagoes from Queretaro, Mexico. Keys to the adults and nymphs are provided and notes on the biology of the species are included. Phyletic relationships among the three genera were inferred from morphological characters. Neochoroterpes and Euthraulus were shown to have a sister group relationship to Choroterpes. The phyletic relationships among the species of Neochoroterpes is also proposed. A cladogram based on morphological characters and a single, diagnostic electrophoretic character was constructed. This cladogram was tested by comparisons with a phenogram and a cladogram derived from electrophoretic data alone; all three dendograms were congruent. The phylogenetic analysis is further tested by a zoogeographic analysis which is congruent with known geological events, paleohydrology, and the present hydrology of southwestern North America. The sister group relationships of Euthraulus and Neochoroterpes would represent a vicariance event between eastern Asian and western North America across Beringia in the mid Cenozoic. This history represents a leptophlebiid zoogeographical pattern distinctly different from the Laurasian and Gondwanian patterns already recognized. Choroterpes (s.s.) itself may have evolved in western Eurasia, where it was isolated by epicontinental seas from Euthraulus-Neochoroterpes, and dispersed to eastern North America by the De Greer route. Neochoroterpes speciation events correspond to the following vicariance events: N. kossi was isolated on the Colorado Plateau, N. moctezuma in the Rio Panuco in the southern Sierra Madre Oriental of Mexico, N. nanita in streams of the Edwards Plateau of Texas, and N. oklahoma in the east flowing streams of the Sierra Madre Occidental of Mexico. Subsequent dispersal events associated with the development of the hydrology of the area have modified this vicariance pattern, especially for N. oklahoma and to some extent for N. kossi. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Zoology." |
| Physical Description: | xiii, 129 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |