First checklist, species richness and diversity of leaf-litter dwelling ants (Hymenoptera: Formicidae) in ancient Benin moat, Nigeria

Abstract

Encircling Benin City, in Nigeria, lies an enormous excavation commonly known as a moat or ‘Iya’ by the people of Benin or the Great Benin Kingdom, which dates back several centuries and holds diverse, but poorly known faunal and floral species. To catalogue its leaf-litter ant species, 24 10-m² quadrats randomly sited within the moat were sampled with a leaf-litter sampler (sifter) and the collected ants were euthanised in properly labelled enclosed jars containing a ball of cotton charged with ethyl acetate. Results revealed eight species of ants distributed among eight genera and four subfamilies (Dolichoderinae, Formicinae, Myrmicinae and Ponerinae). Pheidole megacephala was the most abundant species followed by Odontomachus troglodytes. Diversity indices revealed a heterogeneous community of ants at microhabitat levels notably dominated by P. megacephala, while five species were rare. The study predicts an additional ant collection of 27 to 45 % to realise the complete inventory of litter ants in the moat, which typifies an isolated green space capable of retaining several species despite pressure from urbanisation.