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Windhoek, Namibia

Dumbacher J.P.,California Academy of Sciences | Rathbun G.B.,California Academy of Sciences | Osborne T.O.,California Academy of Sciences | Griffin M.,Ministry of Environment and Tourism | Eiseb S.J.,National Museum of Namibia
Journal of Mammalogy | Year: 2014

While studying the systematics and taxonomy of round-eared sengis (genus Macroscelides), we identified an unusual specimen from remote northwestern Namibia in the collection of the California Academy of Sciences. To determine if this represented a different species, we made 9 collecting trips with 5,616 trap-nights of effort that produced 16 voucher specimens (including the original specimen) of the unusual sengi. These specimens are distinguished from other Macroscelides species by morphological metrics (they are smaller), external features (rusty-tinged pelage, large subcaudal gland, and lack of dark skin pigment), and by divergence at 3 independently segregating DNA loci. These traits are the basis for the description of a new species of Macroscelides that seems to be confined to gravel plains associated with the distinctive reddish colored Etendeka geological formation of northwestern Namibia. The new species appears to be reproductively isolated from congeners, because portions of its distribution are sympatric with that of the Namib round-eared sengi (M. flavicaudatus), and we found no evidence of hybrid individuals or gene flow. The new species is allopatric with the Karoo round-eared sengi (M. proboscideus), which is found about 500 km to the south. The new species, along with M. flavicaudatus, is endemic to Namibia. With this 3rd species in the genus, there are now 19 recognized extant species in the order Macroscelidea. © 2014 American Society of Mammalogists.

Katakweba A.A.S.,Sokoine University of Agriculture | Mulungu L.S.,Sokoine University of Agriculture | Eiseb S.J.,National Museum of Namibia | Mahlaba T.A.,University of Swaziland | And 4 more authors.
African Zoology | Year: 2012

The prevalence of haemoparasites, leptospirosis and Yersinia pestis was investigated in rodents and shrews from Tanzania, Namibia and Swaziland. Blood smears originating from rodents and shrews from the three countries indicated the presence of Trypanosoma lewisi (72.7%; n =950), Bacillus spp. (25.6%; n =950), Borrelia sp. (0.01%; n =950) and bipolar coccobacilli (0.01%; n =950). The blood smears from Namibia (n =26) had no haemoparasites while only 1.33% (n =75) of those from Swaziland showed presence of T. lewisi. Leptospira interrogans was found in rodent blood sera from Tanzania in the following serogroup proportions (n =350): Icterohaemorrhagiae (10.29%), Pomona (2.86%), Hardjo (1.14%), Bullum (0.86%), Grippotyphosa (1.43%) and Canicola (1.14%). Serodiagnosis of antibodies against the F1 antigen of Y. pestis using the enzyme linked immunosorbent assay (ELISA) was negative for all the serum samples from central Tanzania, while two samples of serum from two species of rodents, Rhabdomys pumilio and Gerbilliscus leucogaster, collected in the Kavango Region of Namibia were positive. These results suggest an enzootic plague activity in this region in Namibia. It is concluded that zoonotic agents, that are infectious to humans, are prevalent in rodents and shrews in the three countries, and that local communities should apply rodent control measures to reduce the risk of human infections.

Monadjem A.,University of Swaziland | Mahlaba T.A.,University of Swaziland | Dlamini N.,University of Swaziland | Eiseb S.J.,National Museum of Namibia | And 6 more authors.
Wildlife Research | Year: 2011

Context Rodent pests can have severe impacts on crop production in sub-Saharan Africa. In particular, the multimammate mouse Mastomys natalensis severely damages agricultural crops in southern and eastern Africa, leading to significant losses. Both its population ecology and breeding biology have been studied in agricultural and natural habitats. Population numbers erupt depending on the timing and amount of rainfall and may reach plague proportions, especially in agricultural settings, where it may become a serious pest. However, the ecology of this species, in particular its interactions with other species within the context of human settlement, is poorly understood. It may occasionally enter houses, but the degree to which it does so and the factors influencing this movement are not known. Aims We investigated the relationship between Rattus spp. and M. natalensis entering buildings in an agro-ecological setting. We predicted that M. natalensis would enter houses more readily when food availability was lowest in the surrounding fields, and when the larger Rattus spp. were absent. Methods We followed 40 individuals of M. natalensis in Swaziland and Namibia by radio-telemetry. Mice were captured in maize fields within 50m of a homestead and fitted with radio-transmitters at three different times corresponding to different stages of crop development: pre-harvest, post-harvest and pre-planting. To corroborate the findings of the telemetry study, a non-toxic marker, rhodamine B, was mixed with standard bait and left at bait stations inside houses in 10 homesteads in Swaziland and Tanzania. Key results Mice remained in the fields during the entire period of study in Swaziland, but entered buildings in Namibia during the post-harvest stage, which may represent a period of food shortage for these mice in the field. Rodents captured after baiting with rhodamine B demonstrated that Rattus spp. predominated within the houses. A small number of rhodamine B-marked M. natalensis were captured outside the houses, the proportion declining with distance away from the houses. Conclusions These results suggest that in a typical rural African setting dominated by subsistence agriculture, Rattus spp. (when present) competitively exclude the smaller M. natalensis from entering houses. Implications Interactions between rodent pest species may be important in determining which rodent species enter houses in rural African landscapes. Consideration of such interactions may play an important role when developing pest management strategies. © 2011 CSIRO.

Bird T.L.,National Museum of Namibia | Wharton R.A.,Texas A&M University
African Invertebrates | Year: 2015

Melanoblossiidae Roewer, 1933 is a small family of solifuges (Solifugae, Arachnida), comprising two subfamilies: Melanoblossiinae Roewer, 1933 and the monotypic Dinorhaxinae Roewer, 1933. The Melanoblossiinae consists of 15 currently recognised species, restricted to southern Africa. A new species, Melanoblossia ansie sp. n., placed in the Melanoblossiinae, is described from Namibia. This brings to five the number of species in Melanoblossia Purcell, 1903, and is the first record of Melanoblossia from Namibia. The flagellum and principal seta of the setiform flagellar complex characteristic of Melanoblossiinae are discussed. © FUNPEC-RP.

Klann A.E.,University of Greifswald | Bird T.L.,National Museum of Namibia | Talarico G.,Max Planck Institute for Chemical Ecology
Journal of Arachnology | Year: 2011

The family Hexisopodidae is endemic to southern Africa. Hexisopodids represent a very peculiar group of Solifugae. They differ from all other solifuge families through various autapomorpic adaptations to a subterranean mode of life, most notably the presence of fossorial legs. The phylogeny of the Solifugae is widely unresolved. The ultrastructure of spermatozoa has successfully been used for phylogenetic analyses in other animal taxa. Therefore, the question arose whether the morphological peculiarity of the family Hexisopodidae might also be reflected in the ultrastructure of their spermatozoa. This was investigated for Hexisopus psammophilus Wharton 1981 (Hexisopodidae). Spermatozoa do not seem to aggregate in the testes, nor in the vasa deferentia. Sperm cells are aflagellate, roundish, and with irregularly shaped chromatin bodies. Each sperm is surrounded by a secretion sheath, thus representing a typical cleistosperm, the first record of this form of sperm transfer in solifuges. The sperm cells form finger-like protuberances and contain putative granules of glycogen, features shared with the Ammotrechidae, Da siidae and Solpugidae. The acrosomal complex shows additional similarity with the Solpugidae. Overall, the spermatozoa of H. psammophilus share some morphological features with the Ammotrechidae and Daesiidae, but mostly resemble that of the family Solpugidae. © 2011 The American Arachnological Society.

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