|
Chironomus nipponensis Tokunaga 1940 Morphological and molecular data both clearly indicated that there were two species included under this name, referred to as the "Lowland type" and the "Highland type". An examination of specimens from the type locality by M. Hashimoto (M. Yamamoto, personal communication), confirmed that the "Highland type" was the true C. nipponensis, while the "Lowland type" was C. fujitertius Sasa. The following description is based on Sasa (1975) who described the correct form. Adult A large black species, ground color of scutum silvery white, stripes brown, scutellum brownish yellow, postnotum dark brown; abdominal segments with pale apical bands. Wing length 4.8 mm; VR approximately 1. Head: AR 3.8, frontal tubercles 50 x 21 µm; palpal proportions (segs 2-5; micron) 110 : 310 : 350 : 540). Leg lengths and proportions:
Anal point broad, wider at base than apex; Superior volsella E-type of Strenzke (1959), similar to that of C. anthracinus (Yamamoto 2010), setae branched. Female: Pupa: Only the number of spines on the spur of segment VIII noted: 3 (2-4). Fourth instar larva: The larva is called a plumosus-type, but Sasa's illustration suggests it could be a melanotus-type. The lateral tubules are small; anal tubules about half as long as the posterior prolegs and not constricted in the middle. The illustration suggests that the mentum is type II-III (i.e. 4th laterals reduced almost to the level of the 5th laterals), and the central teeth could be type II, while the third inner tooth of the mandible seems to be well developed (type III). Cytology: - no information. Found: (JAPAN - Sakhalin Island, Sikuka, Karahuto, RUSSIAN JAPAN (Type locality); Molecular,: MtCO1 sequence shows some differentiation between high and low altitude populations (Kondo et al. 2016), consistent with the view of Yamamoto (2010) that there were morphological differences between these habitats. Subsequently clarified that the "Highland form" is C. nipponensis, while the "Lowland form" is C. fujitertius Sasa. |