Riberazantaena, a new hydraenid genus from the Eastern Arc Mountains of Tanzania (Coleoptera, Hydraenidae)

A new genus, Riberazantaena gen. nov., is erected to accommodate Protozantaena grebennikovi Perkins, 2009 and Riberazantaena latissima sp. nov. from the South Pare Mountains in Tanzania. Both species are apparently endemic to Eastern Arc mountain forests, adults living terrestrially in damp leaf litter. Protozantaena Perkins, 1997 is redefined in light of the description of the new genus, and a revised key to genera of Parhydraenini is provided.

Mapping Natural Forest Remnants with Multi-Source and Multi-Temporal Remote Sensing Data for More Informed Management of Global Biodiversity Hotspots

Global terrestrial biodiversity hotspots (GBH) represent areas featuring exceptional concentrations of endemism and habitat loss in the world. Unfortunately, geospatial data of natural habitats of the GBHs are often outdated, imprecise, and coarse, and need updating for improved management and protection actions. Recent developments in satellite image availability, combined with enhanced machine learning algorithms and computing capacity, enable cost-efficient updating of geospatial information of these already severely fragmented habitats. This study aimed to develop a more accurate method for mapping closed canopy evergreen natural forest (CCEF) of the Eastern Arc Mountains (EAM) ecoregion in Tanzania and Kenya, and to update the knowledge on its spatial extent, level of fragmentation, and conservation status. We tested 1023 model possibilities stemming from a combination of Sentinel-1 (S1) and Sentinel-2 (S2) satellite imagery, spatial texture of S1 and S2, seasonality derived from Landsat-8 time series, and topographic information, using random forest modelling approach. We compared the best CCEF model with existing spatial forest products from the EAM through independent accuracy assessment. Finally, the CCEF model was used to estimate the fragmentation and conservation coverage of the EAM. The CCEF model has moderate accuracy measured in True Skill Statistic (0.57), and it clearly outperforms other similar products from the region. Based on this model, there are about 296,000 ha of Eastern Arc Forests (EAF) left. Furthermore, acknowledging small forest fragments (1–10 ha) implies that the EAFs are more fragmented than previously considered. Currently, the official protection of EAFs is disproportionally targeting well-studied mountain blocks, while less known areas and small fragments are underrepresented in the protected area network. Thus, the generated CCEF model should be used to design updates and more informed and detailed conservation allocation plans to balance this situation. The results highlight that spatial texture of S2, seasonality, and topography are the most important variables describing the EAFs, while spatial texture of S1 increases the model performance slightly. All in all, our work demonstrates that recent developments in Earth observation allows significant enhancements in mapping, which should be utilized in areas with outstanding biodiversity values for better forest and conservation planning.

Tazarcus, a new phylogenetically unplaced genus of two flightless weevils with metapleural ridge from the Eastern Arc Mountains, Tanzania (Coleoptera: Curculionidae: Molytinae)

This paper reports new flightless forest litter weevils discovered in Tanzania. They are classified into two species of the genus Tazarcus gen. nov.: T. aeaea sp. nov. (the type species; from South Pare and West Usambara) and T. ogygia sp. nov. (Rubeho). Both new species inhabit the archipelago-type Eastern Arc Mountain rainforests renowned for the high diversity of their biota. Adults of Tazarcus are recognizable by their relatively small size (length of pronotum and elytra in dorsal view 2.0–3.4 mm), the short and straight rostrum covered dorsally with dense velvety pilosity, an antennal funicle with seven segments, a prosternal canal, procoxae separated, a lack of hind wings and effaced elytral shoulders. Remarkably, adults of Tazarcus possess a short longitudinal ridge on each metapleuron, which bears a line of serration likely homologous to sclerolepidia. A phylogenetic analysis of 72 terminals and 3134 aligned positions from one mitochondrial and two nuclear ribosomal fragments corroborated the monophyly of the new genus, of both new species and of all three sampled populations but did not identify the sister group of Tazarcus. Three other weevil taxa with adults possessing a similarly shaped metapleural ridge (the African Thrombosternus Marshall and Allocycloteres Voss and an unidentified species of Molytinae from Madagascar) did not cluster with Tazarcus, suggesting multiple origins of this structure. Tazarcus is taxonomically classified as incertae sedis in a non-monophyletic subfamily “Molytinae”. Images and DNA sequences of all 72 herein analysed specimens are available online at dx.doi.org/10.5883/DS-VGDS011.

Acridocarpus taitensis (Malpighiaceae), a new species from Taita Hills in Kenya, Eastern Arc Mountains

Acridocarpus taitensis (Malpighiaceae), a new species collected from Taita Hills (Ngangao Forest fragment), Kenya, is described and illustrated. The new entity is similar to A. congestus, but is distinguished by its longer glandular leaves, with markedly impressed lateral veins on the adaxial leaf surfaces, smaller bracts, and fruits with the apex of the wings obtuse in shape. This species has previously been recorded as Acridocarpus sp. in the book Kenya, Trees & Shrubs and as Acridocarpus taxon A in the book Kenya, Trees, Shrubs & Lianas.

New Agraeciini species from the Eastern Arc Mountains, East Africa (Orthoptera: Tettigoniidae; Conocephalinae; Agraeciini)

Eleven new Agraeciini species are described. Six species of Afroanthracites are new to science from the North and South Pare, the West and East Usambara, the Udzungwa Mountains of Tanzania, and the Taita Hills of Kenya. The two Afroanthracites Hemp & Ingrisch, 2013 species from the Pare Mountains, A. guttatus n. sp. and A. maculatus n. sp., and A. magamba n. sp., from Magamba Forest Reserve in the West Usambara Mountains are morphologically closely related to each other and form a morphological lineage with the already described species from the West Usambara Mountains (A. discolor Hemp, Ingrisch & Ünal, 2013 and A. pseudodiscolor Hemp, 2015) and A. pommeri n. sp. from the Taita Hills of Kenya. A. lineatus n. sp. from Lutindi Forest Reserve in the East Usambara Mountains has its morphologically closest relative in A. jagoi Ünal & Hemp, 2013 endemic to the Mazumbai Forest Reserve of the West Usambara Mountains while A. montium (Sjöstedt, 1910) from the Kilimanjaro/Meru area, A. inopinatus n. sp. from the South Pare Mountains and A. usambaricus (Sjöstedt, 1913) from the West Usambara Mountains form another morphological lineage. Morphological traits like the shape of the last abdominal tergite in males, the male cerci and the colour pattern suggest at least two lineages reflecting dispersal of the ancestors at a time when forest connected the mountain ranges in the past during climatic fluctuations. In the genus Afroagraecia Ingrisch & Hemp, 2013 new species were collected on Zanzibar and in Kazimzumbwi Forest Reserve, the Udzungwa and Nguru Mountains. Distribution patterns and the morphology suggest recent speciation patterns of Afroagraecia in the Eastern Arc Mountains and along the Tanzanian coast. From the Nguru Mountains a third Dendrobia species of the genus, D. plagata n. sp., is described.