Taxonomy and species diversity of urban forest myriapods in Kathmandu Valley, Nepal

Abstract

This study aimed to identify the Myriapoda fauna of urban forest patches inside the Kathmandu Valley. Samples were collected from May to December 2022 at three urban forest patches: Coronation Garden of Tribhivan University, Ranibari Community Forest, and Nilbarahi Community Forest. Direct search and hand collection of myriapod samples was done during pre-monsoon (May–June), monsoon (July–August), and post-monsoon (December), in the 2 m x 2 m size plots within two parallel transects at 10 m distance. A total of 10 species of Myriapoda belonging to two classes (Diplopoda and Chilopoda), seven families, and eight genera were reported. Two species of the class Diplopoda Gonoplectus ranibariensis sp. nov. and Gonoplectus nibarahiensis sp. nov. were described new to science. Three new records to Nepal were reported Trigoniulus corralinus (Eydoux and Souleyet, 1842), Rhysidatrispinosa Jangi & Dass, 1984, and Scutigera coleoptera (Linnaeus, 1758). New distribution records were made for Delarthrum elegans (Golovatch, 1992), Oxidusgracilis (C.L. Koch, 1847), Koponenius biramus Golovatch and Vandenspiegel, 2014, Rhysida afra (Peters, 1855) and Cryptops dorae Pocock, 1891. None of the common species recorded from three forest patches. Most species are unique to each forest. G. ranibariensis sp. nov., T. corallinus, R. trispinosa, and C. dorae are unique for Ranibari Community Forest, K. biramus for Nilbarahi Community Forest, and O. gracilis for Coronation Garden of Tribhivan University. G. nilbarahiensis sp. nov., D. elegans, R. afra are common for Ranibari Community Forest and Nilbarahi Community Forest. S. coleoptera was a common species distributed in the Ranibari Community Forest and Coronation Garden of Tribhivan University. The Diplopoda (n=344, six species) was most abundant and diverse class followed by Chilopoda (n=73, four species). The abundance of Myriapoda is approximately similar in Ranibari Community Forest (n=211) and Nilbarahi Community Forest (n=203) and but lower in Coronation Garden of Tribhuvan University (n=3). Species diversity in Ranibari Community Forest (𝐻 ′ = 1.71) is higher than other two forest patches: Nilbarahi Community Forest (𝐻 ′ = 0.35) and Coronation Garden of Tribhuvan University (𝐻 ′ = 0.64). The abundance of Myriapod is higher in pre-monsoon (n=330) but species diversity is similar in premonsoon and monsoon (eight species). Higher abundance of Diplopoda was recorded during pre-monsoon while Chilopoda during monsoon. The abundance and species diversity of Myriapoda was affected by forest type, human activities, and season which altered the percentage and size of the litter layer.