Family Diplopeltidae Filipjev, 1918
Diagnosis (emended after Fonseca & Bezerra 2014)
Cuticle visually smooth, finely striated or coarsely annulated.Lateral alae absent.Somatic sensilla present. Inner and outer labial sensilla papilliform. Cephalic sensilla setiform; their bases located at the base of the labial region, anterior to amphidial fovea. Cervical (paramphidial) sensilla present in some genera, located at the level of the amphid and posterior to it. Deirid absent. Ocelli present or absent. Amphidial fovea unispiral or loop-shaped. Secretory-excretory system present. Oral opening apical or shifted either to dorsal or ventral body side. Buccal cavity tubular, cylindrical or undifferentiated. Teeth-like structures absent. Pharynx variable in shape; pharyngeal lumen uniform in thickness along the entire pharynx length; valves absent. Female reproductive system didelphic-amphidelphic or monodelphic-prodelphic. Ovaries outstretched or reflexed antidromously. Male reproductive system diorchic. Posterior testis is either anteriorly oriented and reflexed in the anterior section (reflexed terminal section of the germinal zone) or is posteriorly directed. Spicules symmetrical; gubernaculum present. Precloacal sensilla present in some genera. Three caudal glands present, their nuclei are incaudal. Caudal glands open separately via three pores, or together via a common spinneret.
Araeolaimus de Man, 1888
= Araeolaimoides de Man, 1893
= Coinonema Cobb, 1920
= Parachromagaster Allgén, 1929
Belgopeltula gen. nov.
Campylaimus Cobb, 1920
Cylindrolaimus de Man, 1880
Diplopeltis Cobb in Stiles & Hassal, 1905
= Dipeltis Cobb, 1891
= Discophora Villot, 1875
Diplopeltula Gerlach, 1950
Edalonema Andrássy, 2007
= Adelonema Holovachov & Sturhan, 2003
Intasia Tchesunov & Miljutina, 2008
Metaraeolaimoides De Coninck, 1936
Morlaxia Vincx & Gourbault, 1988
Mudwigglus Leduc, 2013
Pararaeolaimus Timm, 1961
Pseudaraeolaimus Chitwood, 1951
Southerniella Allgén, 1932