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Little is known about the seasonal elevational movements for most tropical avifauna species. Seasonal elevational movements of the Eastern Olive SunbirdCyanomitra olivaceawere studied along an elevational gradient from 600 to 1 500 m above sea level in the Uluguru Mountains, Tanzania, between May 2005 and February 2006. The recapture of ringed individuals along an elevational gradient across seasons provided evidence for the seasonal elevational movement of the Eastern Olive Sunbird in the Uluguru Mountains and the first documented evidence for this species in the Eastern Arc Mountains as a whole. Due to forest fragmentation and lack of corridors connecting high- and low-altitude forests in the Uluguru Mountains, the results have implications for conservation of the forest along the entire elevational gradient as well as for other forest bird species that have been documented to make seasonal elevational movements in the Uluguru Mountains and the entire Eastern Arc Mountains. [ABSTRACT FROM PUBLISHER]

Trypanosoma anguiformis n. sp. and Trypanosoma polygranularis n. sp. are described from the African olive sunbird, Cyanomitra olivacea, and Latham's forest francolin, Francolinus lathami, respectively, based on the morphology of their hematozoic trypomastigotes and partial sequences of the small subunit ribosomal RNA gene. Both new species belong to the group of small non-striated avian trypanosomes (<30 µm in length on average) with the kinetoplast situated close to the posterior end of the body. Trypanosoma anguiformis can be readily distinguished from other small avian trypanosomes due to its markedly attenuated (snake-shaped) form of the hematozoic trypomastigotes and the dumbbell-shaped nucleus of the parasite. Trypanosoma polygranularis is readily distinguishable due to the markedly off-center (anteriorly) located nucleus, numerous azurophilic granules that are arranged in a line following the undulating membrane, and the large kinetoplast (with an area up to 1.7 µm² [1.1 µm² on average]). Illustrations of hematozoic trypomastigotes of the new species are given, and DNA lineages associated with these parasites are reported. The current situation in species taxonomy of avian trypanosomes is discussed. We call for the redescription of valid species of avian trypanosomes from their type vertebrate hosts and type localities by using morphological and polymerase chain reaction-based techniques as an initial essential step towards revising the species composition of avian trypanosomes and reconstructing the taxonomy of these organisms. [ABSTRACT FROM AUTHOR]

Haemoproteus (Parahaemoproteus) cyanomitrae n. sp. (Haemosporida: Haemoproteidae) was found in the olive sunbird, Cyanomitra olivacea (Nectariniidae), in rain forests of tropical Africa. It is described based on the morphology of its blood stages and a segment of the mitochondrial cytochrome b gene (GenBank accession FJ404696), which can be used for molecular identification and diagnosis of this species. Fully grown gametocytes of new parasite are similar to many other species of haemoproteids of passeriform birds, so are not easily distinguishable from many of them at this stage of their development. Haemoproteus cyanomitrae can be readily distinguished from the majority of described species of avian haemoproteids, primarily due to its growing dumbbell-shaped gametocytes and advanced halteridial gametocytes, both of which do not touch the envelope of infected erythrocytes along their entire margin. Pigment granules are most frequently clamped in 1, or several, groups in gametocytes, with larger group of pigment granules usually located close to one end of the gametocyte; asymmetric position of pigment granules in gametocytes a characteristic feature of this parasite. Illustrations of blood stages of the new species are given, and phylogenetic analysis identifies DNA lineages closely related to this parasite, which is widespread in African rain forests, but has been recorded only in the olive sunbird so far. It is probable that H. cyanomitrae is transmitted throughout the range of the olive sunbird in Africa. [ABSTRACT FROM AUTHOR]

Land use changes including deforestation, road construction and agricultural encroachments have been linked to the increased prevalence of several infectious diseases. In order to better understand how deforestation affects the prevalence of vector-borne infectious diseases in wildlife, nine paired sites were sampled (disturbed vs. undisturbed habitats) in Southern Cameroon. We studied the diversity, prevalence and distribution of avian malaria parasites ( Plasmodium spp.) and other related haemosporidians (species of Haemoproteus and Leucocytozoon) from these sites in two widespread species of African rainforest birds, the yellow-whiskered greenbul ( Andropadus latirostris, Pycnonotidae) and the olive sunbird ( Cyanomitra olivacea, Nectariniidae). Twenty-six mitochondrial cytochrome b lineages were identified: 20 Plasmodium lineages and 6 Haemoproteus lineages. These lineages showed no geographic specificity, nor significant differences in lineage diversity between habitat types. However, we found that the prevalence of Leucocytozoon and Haemoproteus infections were significantly higher in undisturbed than in deforested habitats ( Leucocytozoon spp. 50.3% vs. 35.8%, Haemoproteus spp. 16.3% vs. 10.8%). We also found higher prevalence for all haemosporidian parasites in C. olivacea than in A. latirostris species (70.2% vs. 58.2%). Interestingly, we found one morphospecies of Plasmodium in C. olivacea, as represented by a clade of related lineages, showed increased prevalence at disturbed sites, while another showed a decrease, testifying to different patterns of transmission, even among closely related lineages of avian malaria, in relation to deforestation. Our work demonstrates that anthropogenic habitat change can affect host–parasite systems and result in opposing trends in prevalence of haemosporidian parasites in wild bird populations. [ABSTRACT FROM AUTHOR]