This study presents a comprehensive catalogue of the moniligastrid earthworms (Moniligastrida, Moniligastridae) of the world. A total of 176 valid species/subspecies belonging to 5 genera are known to exist in this primitive family. Drawida is the speciose genus with 147 species/subspecies. Of the various moniligastrids, three species of Drawida are considered as peregrine outside its normal Asian range. Among the valid species, occurrence of 30.68% are known only from the type locality. It is noteworthy that the types of 125 (71.02%) species are currently known to exist in various repositories around the world. The existence of the remaining species can only be inferred from the literature since their types are either non-existent, missing, dried out, or lost. Present catalogue includes valid scientific names, synonyms, type locality, type respository details along with registration number, geographic distribution pattern within its native range, and references.

The genus Moniligaster Perrier, 1872 is restricted to the Western Ghats mountain regions of the southern Peninsular India. A new species, Moniligaster julkai Narayanan & Paliwal, sp. nov., is described and illustrated using samples found in the Kerala districts of Kottayam and Pathanamthitta. Apart from that, the status of Moniligaster deshayesi minor Michaelsen, 1913 is critically reviewed, and it is upgraded to species rank as Moniligaster minor Michaelsen, 1913, based on a collection made near its type locality. Furthermore, new distributional records for other Moniligaster species are provided. With this discovery, the genus Moniligaster now has a total of 14 recognised species.

A comprehensive checklist of the earthworm species known from Sri Lanka, an island country in the Indian subcontinent, is presented. In total, 81 species and subspecies belonging to 20 genera and 8 families are recorded. Of these, 58 are Sri Lanka endemics, 2 near endemics and 21 exotics. The checklist includes the type locality, any significant subsequent generic placements, and the distributional pattern with province and districts for each species/subspecies within Sri Lanka.

Two new earthworm species of Megascolex Templeton, 1844, M. quadripapillatus Narayanan & Paliwal, sp. nov. and M. jeyporeghatiensis Narayanan & Paliwal, sp. nov. are described from the under-explored Eastern Ghats Hills of Odisha state in Peninsular India. They belong to a group of species characterized by two pairs of spermathecal pores in intersegmental furrows 7/8/9, holandric, seminal vesicles in segments 9 and 12, absence of penial setae and calciferous glands. Megascolex ratus Cognetti, 1911, M. pumilio Stephenson, 1916 and the two new species described here are the members of this group. Megascolex quadripapillatus sp. nov. and M. jeyporeghatiensis sp. nov. occur in deciduous forests with brownish gravel-loamy soils. Here we provide the detailed description of the external and internal characteristics of the new species along with the illustrations of the key characters. With the new findings, the range of Megascolex genus has been extended further north in the less explored Eastern Ghats Hills of India. With this discovery, the total number of Megascolex species has increased to 70, of which 34 are found in India.

The earthworm fauna of the wetlands of India is highly undocumented. We have carried out a survey of earthworms in the Kuttanad wetland, an integral part of the Vembanad-Kol Ramsar Site, India’s largest wetland of international importance. Current investigation has documented 17 species belonging to 7 families. Megascolex travancorensis pentagonalis Stephenson, 1916 and Glyphidrilus fluviatilis Rao, 1922 were reported for the first time since their original descriptions. Based on the current study, M. t. pentagonalis is raised to species rank as M. pentagonalis from the subspecies status. G. fluviatilis and Lennogaster chittagongensis (Stephenson, 1917) are new records for the state of Kerala. Present results provide a more complete picture of the earthworm fauna of Kuttanad wetland.

In India, studies on above-ground biodiversity have received more attention than those on below-ground biodiversity. With this view, systematic surveys for earthworms were carried out in the Western Ghats mountain range of Kerala state in southwestern corner of Peninsular India. This research resulted in three new records for the state, viz. Drawida nandiensis Stephenson, 1924, D. nepalensis Michaelsen, 1907 and Celeriella bursata Jamieson, 1977. Among these, D. nandiensis and D. nepalensis, are recorded for the first time from the Western Ghats biodiversity hotspot. Previously D. nandiensis and C. bursata were known only from their respective type localities. With the addition of three species the total number of earthworm taxa reported from Kerala state has raised to 128 and now the Western Ghats mountain ranges has 271 species of earthworms.