A new species of genus Hysterothylacium Ward et Magath, 1917 (Nematoda, Anisakidae) from Liparis tanakae (Scorpaeniformes, Liparidae) from the Yellow Sea, China

Abstract A new anisakid nematode, Hysterothylacium liparis sp. nov., is described from the intestine and stomach of the fish, Liparis tanakae (Gilbert et Burke, 1912) (Scorpaeniformes, Liparidae), a fish endemic to the Yellow Sea, China. The new species can be distinguished from the congeners by the absence of lateral alae, the length of the intestinal caecum (1.94–3.35 mm, 58.84–82.47% of oesophageal length), the number and arrangement of the caudal papillae (20–29 precloacal subventral pairs, 1 adcloacal pair and 4 postcloacal pairs), the size of the spicules (1.94–3.74 mm, 4.85–7.30% of body length) and the morphology of the tail tip. This is the first species of adult ascaridoid nematodes to be reported from fishes of the family Liparidae in northern China.