Genus Hylonema

Heteroderinae

Females. No cyst stage. Body long ovoid to globose with prominent neck and no terminal cone. Cuticle thin and annulated only in anterior fore end; posteriorly thick, rugose with non oriented striae. No subcrystalline layer. Vulva subterminal, on flattened posterior body end; vulva lips not protruding. Underbridge present. No phasmids. No remnant of tail. Eggs not retained in female body, but deposited individually in a gelatinous matrix.

Males. Body twisted. Lateral field with four lines. Spicules strong, nearly straight, < 30 um; cloacal tubus short, nearly terminal. No tail. No caudal alae. No phasmids.

Juveniles. Lateral field with three lines. Oesophageal glands filling body cavity. Tail long, elongate with a very long terminal hyaline portion. Phasmids punctiform, small.