Ocnerodrilidae Beddard, 1891

Misirlioğlu, Mete, Reynolds, John Warren, Stojanović, Mirjana, Trakić, Tanja, Sekulić, Jovana, James, Samuel W., Csuzdi, Csaba, Decaëns, Thibaud, Lapied, Emmanuel, Phillips, Helen R. P., Cameron, Erin K. & Brown, George G., 2023, Earthworms (Clitellata, Megadrili) of the world: an updated checklist of valid species and families, with notes on their distribution, Zootaxa 5255 (1), pp. 417-438 : 427

Ocnerodrilidae Beddard, 1891

The widespread Ocnerodrilidae family, with 37 genera and 172 species (plus four subspecies), sister taxon to the Megascolecidae + Acanthodrilidae s.l. clade ( James & Davidson 2012), was last reviewed by Fragoso & Rojas (2009) and Hernández-García et al. (2018), who provided keys to the genera known until then.Two sub-families (Ocnerodrilinae and Malabariinae) were proposed by Gates (1966) and their definitions expanded by Gates (1972) and Fragoso and Rojas (2009). Ocnerodrilinae is more speciose and wider spread, while Malabariinae includes species only from India, China and Myanmar ( Fragoso & Rojas 2009), without extramural glands and internal calciferous lamellae. With the exception of several peregrine species with worldwide distribution, all endemic genera and species of Ocnerodrilinae are confined to South and Central America, sub-Saharan Africa, India ( Curgiona ), and the Seychelles ( Maheina ). A large number of new species and several new genera were recently found in Brazil ( James et al. 2023; HernándezGarcía et al. 2018), and it is likely that further sampling particularly in Northern South America, and in Brazil’s Northeastern region will reveal many more. The majority (27) of the known genera occur in Latin America, while nine genera are known from Africa and five from Asia ( India, China and Myanmar). In Latin America, many of the smaller and pigmented ocnerodriles, particularly in the genera Kerriona and Eukerria inhabit wetlands or bromeliads, and some of them are quite resistant to disturbance, being present in intensively plowed rice or no-tillage row-crop fields in Southern Brazil ( Bartz et al. 2013; Bartz et al. 2014; Ferreira et al. 2023; Lima & Rodríguez 2007).

There are nine widespread anthropochorous ocnerodriles: Eukerria eiseniana (Rosa) , Eukerria kuekenthali (Michaelsen) , Eukerria saltensis (Beddard) , Eukerria stagnalis (Kinberg) , Gordiodrilus elegans Beddard , Gordiodrilus habessinus Michaelsen , Gordiodrilus paski Stephenson , Nematogenia lacuum Beddard , and Ocnerodrilus occidentalis Eisen , that typically live in wet or saturated soils, generally close to water sources. Some of these are of uncertain origin, being possibly of South America or Africa but, in any case, are of Gondwanan or Central Pangean origin ( Fragoso & Rojas 2009). The presence of many parthenogenetic morphs in some species (e.g., O. occidentalis ), has resulted in extensive synonymies which must be checked ( James et al. 2023), although the use of molecular methods may help unravel some of these. The species Nematogenia panamaensis Eisen was synonymized with N. lacuum by Righi (1984a), because variations between the two species were included in a group of specimens collected at the same location in Mato Grosso do Sul, Brazil. Similar to O. occidentalis further work is warranted on these poorly known ocnerodriles, particularly using more detailed genetic methods, in order to confirm the presence of potential cryptic species ( Fragoso & Rojas 2009).