Flying between raindrops : strong seasonal turnover of several Lepidoptera groups in lowland rainforests of Mount Cameroon

1. Although seasonality in the tropics is often less pronounced than in temperate areas, tropical ecosystems show seasonal dynamics as well. Nevertheless, individual tropical insects’ phenological patterns are still poorly understood, especially in the Afrotropics. To fill this gap, we investigated biodiversity patterns of Lepidoptera communities at three rainforest localities in the foothills of Mount Cameroon, West Africa, one of the wettest places in the world. 2. Our multi-taxa approach covered six lepidopteran groups (fruit-feeding butterflies and moths, the families Sphingidae, Saturniidae, and Eupterotidae, and the subfamily Arctiinae of Erebidae) with diverse life strategies. We sampled adults of the focal groups in three distinct seasons. Our sampling included standardised bait-trapping (80 traps exposed for ten days per locality and season) and attraction by light (six full nights per locality and season). 3. Altogether, our dataset comprised 20,576 specimens belonging to 559 (morpho)species of the focal groups. The biodiversity of Lepidoptera generally increased in the high-dry season, and either increased (fruit-feeding moths, Arctiinae, Saturniidae) or decreased (butterflies, Sphingidae) in the transition to the wet season in particular groups. Simultaneously, we revealed a strong species turnover of fruit-feeding Lepidoptera and Arctiinae among the seasons, indicating relatively high specialisation of these communities for particular seasons. 4. Such temporal specialisation can make the local communities of butterflies and moths especially sensitive to the expected seasonal perturbations caused by the global change. Because of the key role of Lepidoptera across trophic levels, such changes in their communities could strengthen this impact on entire tropical ecosystems

A newly discovered biodiversity hotspot of many-plumed moths in the Mount Cameroon area: first report on species diversity, with description of nine new species (Lepidoptera, Alucitidae)

Fifteen species of many-plumed moths are recorded from the Mount Cameroon area, SW Cameroon, West Africa. Nine species: Alucita longipenis Ustjuzhanin & Kovtunovich, sp. n., A. lidiya Ustjuzhanin & Kovtunovich, sp. n., A. ludmila Ustjuzhanin & Kovtunovich, sp. n., A. escobari Ustjuzhanin & Kovtunovich, sp. n., A. mischenini Ustjuzhanin & Kovtunovich, sp. n., A. fokami Ustjuzhanin & Kovtunovich, sp. n., A. janeceki Ustjuzhanin & Kovtunovich, sp. n., A. besongi Ustjuzhanin & Kovtunovich, sp. n., and A. olga Ustjuzhanin & Kovtunovich, sp. n., are described as new for science. Four species are recorded as new from Cameroon: A. acalyptra, A. chloracta, A. coffeina, and A. spicifera. By these records, the Mount Cameroon area has become the richest known Afrotropical locality for the Alucitidae, highlighting its tremendous value for biodiversity conservation

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Biodiversity patterns of butterflies and moths on Mount Cameroon

Biodiversity patterns of butterflies and moths are investigated on the southwestern slope of Mount Cameroon, the only continuous elevational gradient of near-pristine forests in the Afrotropics. Three distinct seasons between 2014 and 2017 are sampled by two standardised methodologies (i.e., bait-trapping and manual catching of selected groups of moths at light). First, the effects of seasonality and forest habitat associations on butterflies and moths are investigated in the lowland rainforest. Then, the impacts of elephant-made natural disturbances on tree, butterfly, and moth diversities at mid-elevations is evaluated. The thesis also includes faunistic records of species never reported from the area, combining them with life history notes on selected taxa and species description of nine new species of Alucita. Finally, the last chapter focuses on the biodiversity of birds, trees, and butterflies in the last large patch of coastal forest of the studied area, and discusses its current conservation status

New records of six moth (Lepidoptera: Erebidae, Lasiocampidae) species in south African countries, with comments on their distribution

Southern Africa hosts a high diversity of ecosystems and habitats with tremendous diversity of Lepidoptera. Although it belongs among most studied parts of the Afrotropics, the knowledge on diversity and distribution of south African moth fauna remains insufficient. To partly fill this gap, we surveyed macromoths by automatic light traps in seven localities in three relatively less sampled south African countries.We reported 14 species and one genus (Remigioides) of moths which have not yet been recorded in Namibia, Botswana, or Zimbabwe. Although none of these records broadened the known distribution of individual species to a new biogeographic region, they still fill important gaps in their distribution. Especially, the known distributional ranges of two species have been substantially extended, although still within the same biogeographic regions: ca. 800 km southwards for Remigioides remigina (Mabille, 1884), and ca. 600 km westwards for Haplopacha cinerea Aurivillius, 1905

New records of six moth (Lepidoptera: Erebidae, Lasiocampidae) species in south African countries, with comments on their distribution

Southern Africa hosts a high diversity of ecosystems and habitats with tremendous diversity of Lepidoptera. Although it belongs among most studied parts of the Afrotropics, the knowledge on diversity and distribution of south African moth fauna remains insufficient. To partly fill this gap, we surveyed macromoths by automatic light traps in seven localities in three relatively less sampled south African countries.We reported 14 species and one genus (Remigioides) of moths which have not yet been recorded in Namibia, Botswana, or Zimbabwe. Although none of these records broadened the known distribution of individual species to a new biogeographic region, they still fill important gaps in their distribution. Especially, the known distributional ranges of two species have been substantially extended, although still within the same biogeographic regions: ca. 800 km southwards for Remigioides remigina (Mabille, 1884), and ca. 600 km westwards for Haplopacha cinerea Aurivillius, 1905

Bigger Helpers in the Ant <i>Cataglyphis bombycina</i>: Increased Worker Polymorphism or Novel Soldier Caste?

<div><p>Introduction</p><p>The mechanisms by which development favors or constrains the evolution of new phenotypes are incompletely understood<b>.</b> Polyphenic species may benefit from developmental plasticity not only regarding ecological advantages, but also potential for evolutionary diversification. For instance, the repeated evolution of novel castes in ants may have been facilitated by the existence of alternative queen and worker castes and their respective developmental programs.</p><p>Material and Methods</p><p><i>Cataglyphis bombycina</i> is exceptional in its genus because winged queens and size-polymorphic workers occur together with bigger individuals having saber-shaped mandibles. We measured seven body parts in more than 150 individuals to perform a morphometric analysis and assess the developmental origin of this novel phenotype.</p><p>Results</p><p>Adults with saber-shaped mandibles differ from both workers and queens regarding the size of most body parts. Their relative growth rates are identical to workers for some pairs of body parts, and identical to queens for other pairs of body parts; critical sizes differ in all cases.</p><p>Conclusions</p><p>Big individuals are a third caste, i.e. soldiers, not major workers. Novel traits such as elongated mandibles are combined with a mix of queen and worker growth rates<b>.</b> We also reveal the existence of a dimorphism in the queen caste (microgynes and macrogynes). We discuss how novel phenotypes can evolve more readily in the context of an existing polyphenism. Both morphological traits and growth rules from existing queen and worker castes can be recombined, hence mosaic phenotypes are more likely to be viable. In <i>C. bombycina</i>, such a mosaic phenotype appears to function both for defense (saber-shaped mandibles) and fat storage (big abdomen). Recycling of developmental programs may have contributed to the morphological diversity and ecological success of ants.</p></div

Distinct adult castes exhibit distinct growth rules.

<p>Growth rules of the worker (empty circles) and queen (empty triangles) castes for a theoretical pair of morphological traits ‘x’ and ‘y’ are illustrated by dashed lines. Increasing critical size of the worker growth rule leads to the production of adults that are larger and have a different shape due to allometry, i.e. major workers (black circles). However the range of possible phenotypes that can be produced is limited (grey area surrounding the workers’ curve). Alternatively, modifying both critical size and growth rate leads to the production of novel adult phenotypes that are outside of this range and accordingly do not belong to the worker caste, i.e. soldiers (empty squares). We suggest that this can be done either by combining parameters of the growth rules of existing worker and queen castes (‘recycled’ soldiers) or by evolving brand new growth rules (‘novel’ soldiers).</p