Order Araeolaimida De Coninck & Schuurmans Stekhoven, 1933

Diagnosis. (Modified from Fonseca & Bezerra (2014) and Lorenzen (1994).) Cuticle smooth, striated, or with transverse rows of punctations. Inner labial sensilla papilliform or not visible; outer labial sensilla and cephalic setae usually in two separate circles. Buccal cavity varies from minute, to cup-shaped or tubular, sometimes equipped with 3–9 odontia (teeth). Amphideal fovea usually loop-shaped or spiral, less commonly bowl-shaped or pore-like. Pharyngeal tubes present in the Comesomatidae and Axonolaimidae and some Diplopeltidae . Pharynx usually cylindrical, sometimes with posterior bulb. Female reproductive system usually with two outstretched ovaries, in some cases only one posterior ovary is present. Males with one or two testes; precloacal supplements sometimes present.