Browsing by Author "Colangelo, P."

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Cytotaxonomy of rodent species from Ethiopia, Kenya, Tanzania and Zambia
(Belg. J. Zool, 2005) Corti, M.; Castiglia, R.; Colangelo, P.; Capanna, E.; Beolchini, F.; Bekele, A.; Oguge, N. O.; Makundi, R. H.; Sichilima, A. M.; Leirs, H.; Verheyen, W.; Verhagen, R.
An extended survey of taxa belonging to two genera of Cricetomyinae (Cricetomys and Saccostomus), one Gerbillinae (Gerbilliscus), eight Murinae (Acomys, Aethomys, Arvicanthis, Lemniscomys, Mus (Nannomys), Mastomys, Grammomys, Stenocephalemys) and one Myoxidae (Graphiurus) was carried out as part of the EU programme “Staplerat” involving Ethiopia, Kenya, Tanzania and Zambia. Here we report the diploid and autosomal fundamental numbers of these rodent taxa. Seventeen of them were unknown, for four we report chromosomal variants and for another 16 new localities where they occur. We discuss their specific status taking into consideration our results together with data from literature and highlight the problems in taxonomy and systematics that are yet to be solved, due do their extended range and the occurrence of species complexes. We highlight cases for which there should be a re-evaluation of specific names that were not included in the last rodent checklist.
Mitochondrial phylogeny reveals diVerential modes of chromosomal evolution in the genus Tatera (Rodentia: Gerbillinae) in Africa
(Elsevier Inc., 2005) Colangelo, P.; Corti, M.; Verheyen, E.; Annesi, F.; Oguge, N.; Makundi, Rhodes H.; Verheyen, W.
The African gerbils of the genus Tatera are widespread and abundant throughout sub-Saharan Africa. There is still today a certain controversy concerning the taxonomy of these rodents and very few attempts have been made to assess their systematic relationships. The present paper introduces Wndings based on the partial sequences of cytochrome b (495 bp) and the 16S rRNA (469 bp) mitochondrial genes of six (T. robusta, T. nigricauda, T. vicina, T. leucogaster, T. valida, and T. kempi) species together with two additional taxa. We also report the karyotypes of T. vicina and T. leucogaster. We propose that T. vicina should be considered as a valid species and show the monophyly of the robusta species group, with the exclusion of T. leucogaster. Our results show there is a diVerent chromosomal evolutionary pattern within the two major lineages, which is recognizable through molecular phylogenetics. One is characterized by karyotype stability and the other by a considerable number of chromosomal rearrangements. The lineage divergence coincides with the formation of the East African Rift. The processes that led to the origin of the East African species seem to be related to the subsequent climatic changes, which caused cyclic contraction and expansion of the savannah biomes. Furthermore, geological activities that characterized East Africa during Plio-Pleistocene may also have contributed to lineage divergence.
The Rodent fauna of Tanzania : a cytotaxonomic report from the Maasai Steppe
(Nella seduta del 12 gennaio, 2001) Fadda, N. di C.; Castiglia, R.; Colangelo, P.; Corti, M.; Machang’u, R.; Makundi, R.; Scanzani, A.; Tesha, P.; Capanna, W. V. E.
The rodent fauna of Tanzanian savannahs is poorly known. For this reason, the Accademia Nazionale dei Lincei sponsored a project together with the Biology Department of Antwerp and the Sokoine University of Agriculture (Morogoro, Tanzania) on Eastern African rodents. The aim was to study the taxonomy and systematics of rodents of these areas and the processes through which rodent biodiversity has increased in these African regions. We present here a report of the expeditions carried out in the Maasai steppe of Tanzania during 1999, with the description of the karyotypes of 13 rodent species. These are: Saccostomus cf. mearnsi (Cricetomynae), Tatera cf. robusta, Gerbillus cf. pusillus (Gerbillinae), Acomys spinosissimus, Acomys wilsoni, Acomys ignitus, Aethomys cf. chrysophilus, Arvicanthis cf. neumanni, Arvicanthis cf. nairobae, Grammomys sp., Lemniscomys rosalia, Lemniscomys cf. zebra, Mastomys natalensis (Murinae). The karyotypes of eight species are described for the first time (Saccostomus cf. mearnsi, Gerbillus cf. pusillus, Acomys wilsoni, Acomys ignitus, Arvicanthis cf. neumanni, Arvicanthis cf. nairobae, Grammomys sp., Lemniscomys rosalia).