Subgenus Hystricochaetonotus Schwank, 1990

Type species: Chaetonotus hystrix Mečnikow, 1865

Terra typica: Russia

A polyphyletic subgenus in terms of molecular data (Kånneby et al. 2013), encompasses 28 nominal freshwater species and 10 marine species (Todaro & d'Hondt 2013). Present in benthic and periphytic habitats.

Character N Ranges SD

Body length 4 80.4–87.9 3.24

Pharynx length 3 21.7–22.4 0.38

Width of anterior pharynx thickening (a) 3 6.7–6.9 0.12

Width of pharynx narrowing that follows anterior thickening (n) 2 3.7–4.4 0.40 Character N Ranges SD Body length 2 80.3–85.0 3.32 Pharynx length 2 19.5–20.1 0.42 Width of anterior pharynx thickening (a) 1 6.9 –

Width of pharynx narrowing that follows anterior thickening (n) 1 3.7 –