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Habitat loss and habitat fragmentation usually occur together, at the same time and place. However, while there is consensus that habitat loss is the preeminent threat to biodiversity, the effects of fragmentation are contentious. Some argue that habitat fragmentation is not bad for biodiversity, and even that it is good. Generally, the studies that find no harm or positive outcomes of fragmentation invariably assume that it is independent of habitat loss. However, dissociating the effects of habitat fragmentation from habitat loss is questionable because of the two are essentially coupled. Accordingly, we evaluated how forest area and fragmentation (via edge effects) influenced dung beetles per se, and through their effects on the abundance of mammals, using structural equation modeling (SEM). Dung beetles are very sensitive to forest habitat loss and fragmentation, and to changes in the abundance of mammals on which they depend for dung. Our study area was in the Tana River, Kenya, where forest fragments are depauperate of mammals except for two endemic species of monkeys. We mapped 12 forests, counted the resident monkeys, and sampled 113,959 beetles from 288 plots. Most of the 87 species of beetles were small, affirming the endemic monkeys as the main source of dung. After implementing a fully latent Structural Regression SEM, the optimal model explained a significant 26% of the variance in abundance, and 89% of diversity. The main drivers of beetle abundance were positive, direct, effects of forest area and number of monkeys, and negative edge effects. The main drivers of diversity were the direct effects of the beetle abundance, indirect effects of forest area and abundance of mammals, and indirect negative edge effects. Thus forest area, fragmentation (via edge effects) and the number of monkeys jointly influenced the abundance and diversity of the beetles directly and indirectly.

The species richness of flora and fauna in the Nzoia River drainage basin is documented through a study of museum specimens, catalogues and databases. The catchment area and basin covers 2.2% (12900/580367 km2) of Kenya's total land area with an altitudinal range of 1140 to 4300 m and varied ecosystem and land uses. We recorded approximately 9.3% (3239/34677) of Kenya's current known species of vascular plants, invertebrates (insects and spiders), fish, amphibians, reptiles, birds and mammals. Bird species made up the highest proportion 58.3% (650/1114) of the national total followed by amphibians 37.3% (41/110), reptiles 45.0% (86/191), mammals 31.3% (122/390), vascular plants 17.9% (1251/7000), fish 6.7% (58/872) (32.2% (58/180) for freshwater fish only) and invertebrates (insects and spiders) 4.1% (1031/25000). Ninety-five species recorded in this area are endemic to Kenya and 42 globally threatened. The species recorded contribute to several ecosystem services including pest control, pollination, bio-indicators, medicine and cosmetics, building materials, ecotourism, research and education. Data available differed substantially across counties and taxon groups with gaps apparent in five counties (Bungoma, Busia, Elgeyo Marakwet, Siaya and Usain Gishu) and four taxa plants, invertebrates, fungi and bacteria where a dearth of information exists. To fill these gaps we recommend prioritisng future survey effort on taxa and counties with fewer than 10% of the total numbers of records.

Many blood-feeding arthropods are known vectors of viruses that are a source of unprecedented global health concern. Mosquitoes are an integral part of these arthropod vectors. Advancements in next-generation sequencing and bioinformatics has expanded our knowledge on the richness of viruses harbored by arthropods. In the present study, we applied a metagenomic approach to determine the intercontinental virome diversity of Culex quinquefasciatus and Culex tritaeniorhynchus in Kwale, Kenya and provinces of Hubei and Yunnan in China. Our results showed that viromes from the three locations were strikingly diverse and comprised 30 virus families specific to vertebrates, invertebrates, plants, and protozoa as well as unclassified group of viruses. Though sampled at different times, both Kwale and Hubei mosquito viromes were dominated by vertebrate viruses, in contrast to the Yunnan mosquito virome, which was dominated by insect-specific viruses. However, each virome was unique in terms of virus proportions partly influenced by type of ingested meals (blood, nectar, plant sap, environment substrates). The dominant vertebrate virus family in the Kwale virome was Papillomaviridae (57%) while in Hubei it was Herpesviridae (30%) and the Yunnan virome was dominated by an unclassified viruses group (27%). Given that insect-specific viruses occur naturally in their hosts, they should be the basis for defining the viromes. Hence, the dominant insect-specific viruses in Kwale, Hubei, and Yunnan were Baculoviridae, Nimaviridae and Iflaviridae, respectively. Our study is preliminary but contributes to growing and much needed knowledge, as mosquito viromes could be manipulated to prevent and control pathogenic arboviruses.