First evidence of aggressive chemical mimicry in the Malagasy orb weaving spider <i>Exechocentrus lancearius</i> Simon, 1889 (Arachnida: Araneae: Araneidae) and description of a second species in the genus

The araneid genus Exechocentrus Simon, 1889 and its type species Exechocentrus lancearius were originally described based on a single female specimen from Madagascar, which was missing the abdomen. The first complete adult specimen, a female, of Excechocentrus lancearius was collected in 2000. A second adult female of Excechocentrus sp. was discovered in 2009, about 300 km away from the first locality. We redescribe the neotype of Exechocentrus lancearius and describe the second adult female as Exechocentrus madilina new species. We also report some observations on the natural history of Exechocentrus lancearius, including photographs of its highly modified foraging web, which provide indirect evidence of aggressive chemical mimicry

Description of one new genus and four new species of mynoglenine spiders from Africa (Araneae: Linyphiidae: Mynogleninae)

The genus Camafroneta gen. nov. is established to accomodate Camafroneta oku gen. et sp. nov., a new species of mynoglenine spider from Cameroon, West Africa, with unusual complex male genitalia. Phylogenetic analyses suggest that the new species does not belong to a known genus of mynoglenine spiders. Another three new species of Afroneta Holm, 1968 from East Africa are described: Afroneta flavescens sp. nov., Afroneta serrata sp. nov. and Afroneta sarahae sp. nov. We also describe the missing sex (♂) of Afroneta elgonensis Merrett, 2004

A landscape-scale assessment of tropical mammals reveals the effects of habitat and anthropogenic disturbance on community occupancy

<div><p>With biodiversity facing unparalleled threats from anthropogenic disturbance, knowledge on the occurrences of species and communities provides for an effective and fast approach to assess their status and vulnerability. Disturbance is most prominent at the landscape-level, for example through habitat loss from large-scale resource extraction or agriculture. However, addressing species responses to habitat changes at the landscape-scale can be difficult and cost-ineffective, hence studies are mostly conducted at single areas or habitat patches. Moreover, there is a relative lack of studies on communities, as opposed to focal species, despite the former may carry more comprehensive information. Here, we used a multi-region, multi-species hierarchical occupancy model to study a meta-community of mammals detected by camera traps across five distinct areas within a heterogeneous landscape in Tanzania, and aimed to assess responses to human disturbance and environmental variables. Estimated species richness did not vary significantly across different areas, even though these held broadly different habitats. Moreover, we found remarkable consistency in the positive effect of distance to human settlements, a proxy for anthropogenic disturbance, on community occupancy. The positive effect of body size and the positive effect of proximity to rivers on community occupancy were also shared by communities. Results yield conservation relevance because: (1) the among-communities consistency in responses to anthropogenic disturbance, despite the heterogeneity in sampled habitats, indicates that conservation plans designed at the landscape-scale may represent a comprehensive and cost-efficient approach; (2) the consistency in responses to environmental factors suggests that multi-species models are a powerful method to study ecological patterns at the landscape-level.</p></div

Reserve size and anthropogenic disturbance affect the density of an African leopard (Panthera pardus) meta-population

Determining correlates of density for large carnivores is important to understand their ecological requirements and develop conservation strategies. Of several earlier density studies conducted globally, relatively few addressed a scale (usually >1000 km2) that allows inference on correlates of density over heterogeneous landscapes. We deployed 164 camera trap stations covering ~2500 km2 across five areas characterized by broadly different vegetation cover in the Udzungwa Mountains, Tanzania, to investigate correlates of density for a widespread and adaptable carnivore, the leopard (Panthera pardus). We modelled data in a spatially explicit capture-recapture framework, with both biotic and abiotic covariates hypothesised to influence density. We found that leopard density increased with distance to protected area boundary (mean±SE estimated effect = 0.44±0.20), a proxy for both protected area extent and distance from surrounding human settlements. We estimated mean density at 4.22 leopards/100 km2 (85% CI = 3.33‒5.35/100 km2), with no variation across habitat types. Results indicate that protected area extent and anthropogenic disturbance limit leopard populations whereas no support was found for prey availability and trap array as drivers of leopard density. Such vulnerability is relevant to the conservation of the leopard, which is generally considered more resilient to human disturbance than other large cats. Our findings support the notion that protected areas are important to preserve viable population of leopards, increasingly so in times of unprecedented habitat fragmentation. Protection of buffer zones smoothing the abrupt impact of human activities at reserve edges also appears of critical conservation relevance

The same but different : equally megadiverse but taxonomically variant spider communities along an elevational gradient

Spatial variation in biodiversity is one of the key pieces of information for the delimitation and prioritisation of protected areas. This information is especially important when the protected area includes different climatic and habitat conditions and communities, such as those along elevational gradients. Here we test whether the megadiverse communities of spiders along an elevational gradient change according to two diversity models - a monotonic decrease or a hump-shaped pattern in species richness. We also measure compositional variation along and within elevations, and test the role of the preference of microhabitat (vegetation strata) and the functional (guild) structure of species in the changes. We sampled multiple spider communities using standardised and optimised sampling in three forest types, each at a different elevation along a climatic gradient. The elevational transects were at increasing horizontal distances (between 0.1 and 175 km) in the Udzungwa Mountains, Eastern Arc Mountains, Tanzania. The number of species was similar between plots and forest types, and therefore the pattern did not match either diversity model. However, species composition changed significantly with a gradual change along elevations. Although the number of species per microhabitat and guild also remained similar across elevations, the number of individuals varied, e.g. at higher elevations low canopy vegetation was inhabited by more spiders, and the spiders belonging to guilds that typically use this microhabitat were more abundant. Our findings reflex the complex effects of habitat-microhabitat interactions on spider communities at the individual, species and guild levels. If we aim to understand and conserve some of the most diverse communities in the world, researchers and managers may need to place more attention to small scale and microhabitat characteristics upon which communities depend.Peer reviewe

Figure 9 from: Wood HM, Scharff N (2018) A review of the Madagascan pelican spiders of the genera Eriauchenius O. Pickard-Cambridge, 1881 and Madagascarchaea gen. n. (Araneae, Archaeidae). ZooKeys 727: 1-96. https://doi.org/10.3897/zookeys.727.20222

An endemic genus of Madagascan spiders (Araneae, Archaeidae, Eriauchenius) is revised. All 20 species of Eriauchenius are described and keyed, of which 14 are new species: Eriauchenius andriamanelo sp. n., Eriauchenius andrianampoinimerina sp. n., Eriauchenius goodmani sp. n., Eriauchenius harveyi sp. n., Eriauchenius lukemacaulayi sp. n., Eriauchenius milajaneae sp. n., Eriauchenius milloti sp. n., Eriauchenius rafohy sp. n., Eriauchenius ranavalona sp. n., Eriauchenius rangita sp. n., Eriauchenius rixi sp. n., Eriauchenius sama sp. n., Eriauchenius wunderlichi sp. n., Eriauchenius zirafy sp. n. Additionally, six species of the new genus Madagascarchaea gen. n. are described and keyed, of which four are new species: Madagascarchaea fohy sp. n., Madagascarchaea lotzi sp. n., Madagascarchaea moramora sp. n., Madagascarchaea rabesahala sp. n. Diagnostic characters for the Madagascan and African genera are described, and based on these characters and previous phylogenetic analyses the following species transfers are proposed: Eriauchenius cornutus (Lotz, 2003) to Afrarchaea; Afrarchaea fisheri (Lotz, 2003) and Afrarchaea mahariraensis (Lotz, 2003) to Eriauchenius. Finally, we propose that the distribution of Afrarchaea be restricted to South Africa. While several Madagascan specimens have previously been identified as Afrarchaea godfreyi (Hewitt, 1919), we argue that these are likely misidentifications that should instead be Eriauchenius