Comprehensive biodiversity assessment of moths in Nigeria rely greatly on accurate species identification. While most of the Nigerian moths are identified effortlessly using their morphological traits, some taxa are morphologically indistinguishable, which makes it difficult for taxon diagnosis. We investigated the efficiency of the DNA barcode, a fragment of the mitochondrial Cytochrome C oxidase subunit I, as a tool for the identification of Nigerian moths. We barcoded 152 individuals comprising 18 morphospecies collected from one of the remaining and threatened rainforest blocks of Nigeria – the Cross River National Park. Phenetic neighbor-joining tree and phylogenetic Maximum Likelihood approach were employed for the molecular-based species identification. Results showed that DNA barcodes enabled species-level identification of most of the individuals collected from the Park. Additionally, DNA barcoding unraveled the presence of at least six potential new and yet undescribed species—Amnemopsyche sp., Arctia sp., Deinypena sp., Hodebertia sp., Otroeda sp., and Palpita sp. The phylogenetic Maximum Likelihood using the combined dataset of all the newly assembled sequences from Nigeria showed that all species formed unique clades. The phylogenetic analyses provided evidence of population divergence in Euchromia lethe, Nyctemera leuconoe, and Deinypena lacista. This study thus illustrates the efficacy of DNA barcoding for species identification and discovery of potential new species, which demonstrates its relevance in biodiversity documentation of Nigerian moths. Future work should, therefore, extend to the creation of an exhaustive DNA barcode reference library comprising all species of moths from Nigeria to have a comprehensive insight on the diversity of moths in the country. Finally, we propose integrated taxonomic methods that would combine morphological, ecological, and molecular data in the identification and diversity studies of moths in Nigeria.

The role of plants as sources of biologically active entities cannot be overstated. Plants belonging to different families with mosquitocidal activity have been discovered in established ethnobotanical and laboratory-based studies. Biological control of mosquitoes using botanicals remains the safest and most environmentally sound alternative to chemical control. The essential oil of two Nigerian Laggera species, L. pterodonta and L. aurita, were investigated with regard to their ability to kill the fourth instar larvae of the malaria vector, Anopheles gambiae. The WHO protocol was adopted for the larvicidal bioassay. Three replicates comprising 20 larvae each were exposed to various concentrations of the essential oil. Larval mortality was observed after 24 and 48 h, respectively. The results show that mortality increased with an increase in concentration and period of exposure. The essential oil of L. pterodonta was found to be the most effective, with LC₅₀ values of 418 and 404 mg/L after 24 and 48 h, respectively, while the essential oil of L. aurita recorded LC₅₀ value of 688 and 642 mg/L after 24 and 48 h, respectively. The GC-MS results reveal that the essential oil of L. pterodonta comprises 50.83% of compounds that have been reported to have larvicidal activity while the essential oil of L. aurita comprises of 43.69% compounds with larvicidal activity. The better activity of L. pterodonta essential oil could be attributed to it having a higher percentage of compounds such as ɤ-terpinene and 4-carvomenthenol with larvicidal activity. The results suggest that the essential oil of the plants have the potential to be used as an eco-friendly approach for the control of mosquitoes.

One of the strategies for the control and elimination of Schistosomiasis is the control of its snail vectors in endemic area as done in other tropical diseases like malaria. However, the only strategy currently practiced for the control of the disease in Nigeria is annual mass administration of preventive chemotherapy (Praziquantel) among school age children while neglecting the control of its snail intermediate host and other control components such as Behavioral Change Campaign (BCC) and Water, Sanitation and Hygiene (WASH). The neglect of malacology and the vector control will slow the elimination timeline and targets of 2030 set by WHO. In this study, we investigated the abundance and seasonal variations of the snail vectors of schistosomiasis and the relationship between the disease among humans and infected snail vectors. A total of 21,282 snails were collected from 13 sites across the 6 area councils of the FCT. 1,451 (6.8%) of the collected snails belong to three species; Biomphelaria pfeifferi (113), Bulinus truncatus (451) and Bulinus globosus (887) that are known to be vectors of Schistosoma mansoni, Schistosoma haematobium and Schistosoma bovis respectively. These three species were all shedding cercariae both at the time of collection and afterwards when they were induced to shed cercariae. The presence and shedding of cercaria by the Bullinus and Biomphelaria species in the studied communities indicates potential risk of infection for humans and other animals who may come in contact with the water. Although the presence of these infected snail vectors was established in all the study villages except in Kuje and Pukafa, the relationship between its presence and the prevalence of the disease were not statistically significant. Nonetheless, a deliberate health orientation of the people through sensitization and health education activities, provision of safe adequate water sources and other WASH amenities to reduce exposure to the disease risk factors will contribute towards the reduction or elimination of the disease.

One of the strategies for the control and elimination of schistosomiasis is the control of its snail vectors in an endemic area, as is done in other tropical diseases like malaria. However, the strategy currently practiced for the control of the disease in Nigeria is the annual mass administration of preventive chemotherapy (Praziquantel) among school-age children while neglecting the control of its snail intermediate host and other control components. The neglect of malacology and vector control will slow the elimination targets and timeline of 2030 set by the WHO. In this study, we investigated the abundance and seasonal variations in the snail vectors of schistosomiasis and the relationship between the disease among humans and infected snail vectors. A total of 21,282 snails were collected from 13 sites across the six area councils of the Federal Capital Territory (FCT). Of the collected snails, 1451 (6.8%) belong to three species: Biomphelaria pfeifferi (0.5%), Bulinus truncatus (2.1%) and Bulinus globosus (4.2%), which are known to be vectors of Schistosoma mansoni, Schistosoma haematobium and Schistosoma bovis, respectively. These three species were all shedding cercariae both at the time of collection and afterwards, when they were induced to shed cercariae. The association between the reported prevalence of the disease and the percentage of snails shedding cercaria were heterogenous across different communities. While Takushara, with a disease prevalence of 46%, had 60% of the cercaria shedding snails, Kwaita sabo pukafa and Guduji, with disease prevalences of 56% and 26% respectively, had no cercaria shedding snails. Similarly, Dagiri rafin shahu and Gwako 1, with disease prevalences of 60% and 38%, had cercaria shedding snails of less than 1%. Nonetheless, the presence of Bulinus and Biomphelaria species in these communities indicates a potential risk of infection for humans and other animals who may come in contact with the water. Consequently, integrated multisectoral control and elimination measures that combine malacological monitoring with behavioral, environmental, and historical epidemiological assessments with a deliberate health orientation of the people through sensitization and health education is advocated to reduce exposure to the disease risk factors and contribute towards elimination of the disease.