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51.
MANPREET KAUR KOHLI THOMAS SCHNEIDER OLE MÜLLER JESSICA L. WARE 《Systematic Entomology》2014,39(1):190-195
Boyeria irene and Boyeria cretensis are species of spotted dragonflies belonging to the ‘darner’ family, Aeshnidae. In 1991, Peters classified Boyeria from Crete as B. cretensis, based on adult morphological characters. In this study, we used molecular evidence to determine if indeed B. irene and B. cretensis are different species. DNA was sequenced from samples of B. irene (from France, Switzerland, Tunisia, Spain and Italy) and B. cretensis (from Crete). These species were recovered as two different clades with strong support. We conclude that B. irene and B. cretensis are different species, with evidence based on molecular and morphological differences. In addition, we present the first phylogenetic hypothesis for Boyeria for which we have sequenced all but three species. Lastly, we discuss different scenarios that may have led to the present‐day distribution and speciation patterns of Mediterranean Boyeria. 相似文献
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A field technique for the determination of zooplankton grazing on natural bacterioplankton 总被引:3,自引:0,他引:3
PETER KOEFOED BJøRNSEN JENS BRENNER LARSEN OLE GEERTZ-HANSEN MICHAEL OLESEN 《Freshwater Biology》1986,16(2):245-253
SUMMARY. 1. A method for the determination of zooplankton community grazing rates on natural populations of bacteria is described.
2. Undisturbed zooplankton samples were incubated with3 H-thymidine-labelled bac teriioplankton, and animals and their food subsequently separated by size.
3. Prehandling of zooplankton by concentration before incubation reduce the grazing rates by a factor ranging from three to four.
4. Time series experiments showed that appropriate incubation periods ranged from 40 min at 14°C to 60 min at 10°C.
5. Spatial variability in the zooplankton was the main source of the overall standard error. This was considerably reduced by using composite samples. 相似文献
2. Undisturbed zooplankton samples were incubated with
3. Prehandling of zooplankton by concentration before incubation reduce the grazing rates by a factor ranging from three to four.
4. Time series experiments showed that appropriate incubation periods ranged from 40 min at 14°C to 60 min at 10°C.
5. Spatial variability in the zooplankton was the main source of the overall standard error. This was considerably reduced by using composite samples. 相似文献