The biodiversity of West and Central Africa is understudied, including butterflies and moths (Lepidoptera). Cameroon, through its position in between few biogeographic regions and diversity of habitats, is an important hotspot of lepidopteran diversity. However, the country also ranks low when it comes to local biodiversity knowledge. During our long-term ecological projects in the Cameroonian part of the Gulf of Guinea Highlands, we collected rich material of butterflies and moths, including a number of interesting faunistic records. In this study, we report 31 species of butterflies and moths which have not yet been recorded in Cameroon. These species comprised eight new genera records for the country. In many cases, our records represented an important extension of the species’ known distribution, including ten species whose distribution ranges extended into the Guinean biogeographic region. We also comment on the species’ elevational distribution ranges on Mount Cameroon where most of our records originated. Additionally, we confirm the presence of a butterfly Telchinia encedena, after more than a century since its first and so far its only record in Cameroon.

Mount Cameroon, SW Cameroon, has already been described as a unique hotspot of the many-plumed moth (Lepidoptera, Alucitidae), with their local diversity unrivalled in the entire Afrotropics. We confirm its importance with description of seven new species: Alucita bakweri Ustjuzhanin & Kovtunovich, sp. nov., Alucita jana Ustjuzhanin & Kovtunovich, sp. nov., Alucita bakingili Ustjuzhanin & Kovtunovich, sp. nov., Alucita tatjana Ustjuzhanin & Kovtunovich, sp. nov., Alucita zuza Ustjuzhanin & Kovtunovich, sp. nov., Alucita deja Ustjuzhanin & Kovtunovich, sp. nov., and Alucita bokwango Ustjuzhanin & Kovtunovich, sp. nov. These descriptions have raised the known local diversity of many-plumed moth species on Mount Cameroon to 22, i.e., over a quarter of the known Afrotropical biodiversity of this group. This study also emphasises the great conservation importance of the area.

Biodiversity research in tropical ecosystems—popularized as the most biodiverse habitats on Earth—often neglects invertebrates, yet invertebrates represent the bulk of local species richness. Insect communities in particular remain strongly impeded by both Linnaean and Wallacean shortfalls, and identifying species often remains a formidable challenge inhibiting the use of these organisms as indicators for ecological and conservation studies. Here we use DNA barcoding as an alternative to the traditional taxonomic approach for characterizing and comparing the diversity of moth communities in two different ecosystems in Gabon. Though sampling remains very incomplete, as evidenced by the high proportion (59%) of species represented by singletons, our results reveal an outstanding diversity. With about 3500 specimens sequenced and representing 1385 BINs (Barcode Index Numbers, used as a proxy to species) in 23 families, the diversity of moths in the two sites sampled is higher than the current number of species listed for the entire country, highlighting the huge gap in biodiversity knowledge for this country. Both seasonal and spatial turnovers are strikingly high (18.3% of BINs shared between seasons, and 13.3% between sites) and draw attention to the need to account for these when running regional surveys. Our results also highlight the richness and singularity of savannah environments and emphasize the status of Central African ecosystems as hotspots of biodiversity.

This study confirms Mount Cameroon as an unprecedented hotspot for the diversity of many-plumed moths, with the discovery and description of nine new species: Alucita fako Ustjuzhanin & Kovtunovich, sp. nov., Alucita pyrczi Ustjuzhanin & Kovtunovich, sp. nov., Alucita sroczki Ustjuzhanin & Kovtunovich, sp. nov., Alucita potockyi Ustjuzhanin & Kovtunovich, sp. nov., Alucita sedlaceki Ustjuzhanin & Kovtunovich, sp. nov., Alucita tonda Ustjuzhanin & Kovtunovich, sp. nov., Alucita erzayi Ustjuzhanin & Kovtunovich, sp. nov., Alucita sokolovi Ustjuzhanin & Kovtunovich, sp. nov., and Alucita hirsuta Ustjuzhanin & Kovtunovich, sp. nov. Additionally, four additional species are reported from the Mount Cameroon area as new for the country: Alucita agassizi, Alucita dohertyi, Alucita plumigera, and Alucita rhaptica. Of the 89 Alucitidae known from the Afrotropics, the studied area hosts 36 species, most of which are endemic to the area. This unprecedented level of diversity and endemism within this lepidopteran family highlights Mount Cameroon’s significance as a stronghold for specialised insect taxa. Efficient conservation efforts are necessary to protect these ecosystems and their associated unique microlepidopteran diversity.