Orthoptera Tettigoniidae as indicators of biodiversity hotspots in the Guinean Forests of Central and West Tropical Africa

The present paper has two aims: 1) to present the results of the study of selected species of Orthoptera Tettigoniidae collected in the Guinean forests of West Africa and in the important hotspot of Dzanga-Ndoki National Park (Central African Republic); 2) to carry out a check-list of six subfamilies of Tettigoniidae (Pseudophyllinae, Conocephalinae, Hexacentrinae, Phaneropterinae, Mecopodinae and Hetrodinae) living in Central-West tropical Africa, in particular in two main tropical forests, in the subregion of upper Guinea, and in the subregion Nigeria-Cameroon plus the biodiversity hotspots of Central African Republic and Gabon. Many new records are reported and the following new species are described: Plangia astylata n. sp. from Central African Republic and Gabon, Plangia chopardi n. sp. from Côte d’Ivoire, and Catoptropteryx lineata n. sp. from Liberia. In addition the male of Plangia karschi Chopard, 1954 is described and some taxonomical notes on the recently described Arantia marginata Massa, 2021 are discussed. The new name Pseudorhynchus raggei is proposed for Pseudorhynchus robustus Ragge, 1969, junior primary homonym of Pseudorhynchus robustus Willemse, 1953. Then, the author lists all the Tettigoniidae of the above listed subfamilies presently known in central-west tropical Africa (Guinean forests). This wide tropical area holds important biodiversity hotspots that the author highlights through the study of katydids. Many groups of species tend to isolate and speciate probably more than other groups of insects. Overall, the total number amounts to 332 species, of which 242 live in Cameroon-Nigeria subregion plus Central African Republic and Gabon, 216 in the Upper Guinea subregion. The occurrence of endemic taxa is 35.9 and 40.3%, respectively; this resulted a very high percentage compared to that known for plants and animals in the area. Starting from the list of Tettigoniidae three remarkable biodiversity hotspots were examined, Dzanga-Ndoki National Park (Central African Republic), Mt. Tonkoui and Taï National Park (both in Côte d’Ivoire); overall they hold 134, 81 and 88 species, respectively. It seems that in tropical Africa there is a specific richness gradient with an East-West impoverishment, but also a possible increase of endemism occurrence. However, presently this richness suffers a high decline risk, due to deforestation and environmental degradation, in turn dependent on the inequality between human populations, wars and political instability in some tropical areas.

Some new species of Phaneroptera, Eulioptera and Scolocerca (Orthoptera: Tettigoniidae: Phaneropterinae) from West Tropical Africa

The author describes Phaneroptera abdita n. sp., characterized by only two apical spurs; two new species of Eulioptera, E. iolandae n. sp. with unarmed fore coxae, E. atypica n. sp., with atypical opaque tegmina; and Scolocerca thomasi n. sp., all from West Tropical Africa. In addition, he discusses on the probable only African distribution of Phaneroptera sparsa Stål, 1857, and transfers Dithela longicaudata Massa, 2017 to the genus Eulioptera Ragge, 1956.

DIVERSITY AND DISTRIBUTION OF NIGERIAN LEGUMES (FABACEAE)

This study provides the first comprehensive checklist and analysis of the species of Fabaceae from Nigeria, based on over 5000 herbarium collections and the completed "Flora of West Tropical Africa (FWTA)". We report 552 taxa, belonging to 540 species in 155 genera from six subfamilies, with an outstanding number of taxa (36) representing new records for the country. We mapped the distribution of the species using their occurrence records obtained from GBIF and our own field and herbarium collections. The majority of taxa (43%) was distributed in the savanna vegetation of northern Nigeria, followed by the adjacent tropical forest formations of southern Nigeria (34%), and they were found in highest percentages in Papilionoideae (67%) and Caesalpinioideae (19%), followed by Deterioideae (11%), Cercidoideae and Dialioideae (6% each) and Duparquetioideae (<1%) subfamilies. Endemic and native taxa were 5 and 73% respectively. The most prevalent subfamilies in terms of endemicity were Papilionoideae (14 species), and Deterioideae (11 species), while the most prevalent genera were Indigofera (three species), Dalbergia (three species), Brachystegia (two species) and Cryptosepalum (two species). We found that the majority (37%) of the species were phanerophytes and the fewest were cryptophytes (0.7%). These results suggest that Nigeria has a considerable diversity of legumes, with a predominant distribution in the savanna, probably due to the demanding environmental conditions limiting the dispersion of generalists or invasive species. The diversity of growth forms and distribution patterns of Nigerian legumes could be useful in screening these plants for other potential uses, such as conservation planning or specific agricultural purposes. We recommend a similar study on other families as this will help locals, natural scientists, governments and conservation bodies to recognise and appreciate the flora of the country.

Distribution of Ipomoea violacea (Convolvulaceae): patterns, gaps and reports for its occurrence in Brazil and West Tropical Africa

In 2015 a chance discovery of the beach moon flower in coastal Brazil led to an investigation of the global occurrence, distribution, and abundance of this pantropical littoral plant species. We here document new distribution records for coastal Brazil and West Tropical Africa; postulate a human-mediated long-distance dispersal for this species from the Indo-Pacific to the Atlantic, followed by local distribution via ocean currents; and provide historical context on the name confusion with other species. We also point out the risks inherent in using specimen information available on the internet without adequate verification for the identity of the specimens as a necessary first step.

Flavonoid Composition of Salacia senegalensis (Lam.) DC. Leaves, Evaluation of Antidermatophytic Effects, and Potential Amelioration of the Associated Inflammatory Response

Predominantly spread in West Tropical Africa, the shrub Salacia senegalensis (Lam.) DC. is known because of its medicinal properties, the leaves being used in the treatment of skin diseases. Prompted by the ethnomedicinal use, a hydroethanolic extract obtained from the leaves of the plant was screened against a panel of microbial strains, the majority of which involved in superficial infections. The extract was found to be active against the dermatophytes Trichophyton rubrum and Epidermophyton floccosum. Notable results were also recorded regarding the attenuation of the inflammatory response, namely the inhibitory effects observed against soybean 5-lipoxygenase (IC50 = 71.14 μg mL−1), no interference being recorded in the cellular viability of RAW 264.7 macrophages and NO levels. Relevantly, the extract did not lead to detrimental effects against the keratinocyte cell line HaCaT, at concentrations displaying antidermatophytic and anti-inflammatory effects. Flavonoid profiling of S. senegalensis leaves was achieved for the first time, allowing the identification and quantitation of myricitrin, three 3-O-substituted quercetin derivatives, and three other flavonoid derivatives, which may contribute, at least partially, to the observed antidermatophytic and anti-inflammatory effects. In the current study, the plant S. senegalensis is assessed concerning its antidermatophytic and anti-inflammatory properties.

Description of two new Geissleria species (Bacillariophyta) from Central and West tropical Africa

During a recently started-up project in the Biosphere Reserve at Yangambi, DR Congo, an unknown Geissleria taxon was observed in a small tributary of the Congo River. This taxon is here described as new to science based on detailed light and scanning electron microscopy observations. Geissleria lubiluensis sp. nov. can be distinguished by the slightly tri-undulate valve margins and the very distinct annulus located at a distance of 3 striae from the apex. The comparison of this taxon with various other Geissleria taxa with resembling valve outline or with resembling annulus structure, led to the description of another new species: Geissleria fogedii sp. nov. reported by Foged from Ghana as Navicula paludosa. This taxon resembles very well Geissleria lubiluensis but differs in the distinct annulus located closer to the apex mostly at the distance of one stria, the broader valves and the denser striation.

A reappraisal of Schoenoplectus muricinux (Cyperaceae) including S. confusus and closely allied taxa in Africa

The macro-morphological variation and geographical distribution of six morphologically similar taxa from the Schoenoplectus corymbosus complex with distinctly muricated nutlets (viz Schoenoplectus confusus subsp. confusus var. confusus and var. rogersii, S. confusus subsp. natalitius, S. muricinux, S. muriculatus and Scirpus corymbosus var. junciformis) were thoroughly studied. It is concluded that all these taxa are ill-defined and that alleged distinctive traits are weak or widely overlap. We therefore suggest expanding the description of S. muricinux (the binomial which has nomenclatural priority) and reducing the other species and their infraspecific taxa to synonyms of it. “S. sp. A” of Flora of West Tropical Africa (Nigeria, where it is considered a naturalized introduction of man-made habitats) is shown to also belong to S. muricinux.