C. alpestris Goetghebuer 1934

Adult:

The adults of C. alpestris were well described by Strenzke (1959) as C. dorsalis and C. nippodorsalis was initially described by Sasa (1979), in Japanese.  Re-examination of C. nippodorsalis by Yamamoto and Hashimoto in 1976 convinced them that it was indistinguishable from C. dorsalis (personal communication), and hence from C. alpestris.
Specimens, previously called Sp. PK5, from India and Israel are in the same BOLD Bin and differ from C. alpestris only in the presence of a complex inversion of arm E.
Given the low heterozygosity of European populations (heterozygosity only of arm G) this could represent a very closely related species.
By 2018, Yamamoto and Yamamoto had decided that C. nippodorsalis was not a synonym of C. alpestris due to differences in larval morphology.
There also appears to be a difference in the Superior volsella, which is D-type in C. alpestris but S-type in C. nippodorsalis.

Male:  partly from Strenzke (1959):
Wing length 3.3 (3.07-3.53) mm.  VR 1.08; AR 3.18 (2.96-3.38); LR 1.61 (1.56-1.66); BR 2.4 (2.27-2.53).
Ground color of head and thorax grey-yellow, thoracic vittae black, postnotum uniformly black.  Legs with tarsal segments dark brown.
Thoracic setae: Acrostichals 10.3 (8-13); dorsocentrals 24.4 (21-28); prealar 5.5 (4-8); supra-alar 1.4 (1-2); scutellar 22.9 (19-26).
Legs: Lengths (micron) and proportions:

	Fe	Ti	Ta1	Ta2	Ta3	Ta4	Ta5	LR	F/T	BR
PI	1330	1140	1860	900	790	650	280	1.56-1.66	1.0-1.17	3.2
PII	1410	1285	780	420	300	190	145	0.61-0.65	1.10
PIII	1570	1570	1050	600	440	280	160	0.67	1.0

Ta5/Ti = 0.26

Abdominal coloration similar to C. nippodorsalis, i.e. ground color whitish-yellow, and each segment has a dark brown band: posterior on tergite I, but anterior on other tergites, produced posteriorly on segments II and III.
8-10 setae in pale patches (1-2/patch) on tergite IX.
Anal point narrow at base; Superior volsella of D(e)-type of Strenzke (1959); Inferior volsella reaching almost to end of anal point or about 1/3 of gonostyle and with simple setae; gonostyle only moderately expanded and narrows over posterior half.

Hypopygium (left) and Superior volsella of C. alpestris.

Female: (from Strenzke 1959)
Wing length 3.5 (3-4) mm.  Thoracic setae: Acrostichal 14.0 (11-17); dorsolateral 33.7 (29-39); prealar 5.9 (5-7); supraalar 1.7 (1-2); scutellar 32.2 (28-36).
Relative length of Fore leg segments cf. tibia length: Fe 1.24 ; Ti 1.0 : Ta1 1.65 ; Ta2 0.77 ; Ta3 0.70 ; Ta4 0.60 ; Ta5 0.26.  BR 1.9 (1.7-2.1).
Abdomen largely grey brown, pale areas at posterior of segments slightly larger than those of C. nippodorsalis.

Go to C. alpestris immatures

The synonymy of C. nippodorsalis with C. dorsalis Strenzke was claimed by Yamamoto and Hashimoto in 1976, and, while this conclusion is supported by the DNA analyses of Kondo et al. (2016) based on K2P distance (i.e. in same BOLD Bin), and Langton and Visser (2003) list this as a synonym of C. dorsalis, there are differences in larval morphology (clypeal chaetae fringed at end, VT of equal length) and cytology that support the recognition of C. nippodorsalis.  As well, an analysis of actual base similarity by Dr. Kondo showed 8-10 consistent base differences, while my limited analyses showed no consistent differences, rather a number of unique polymorphisms in each species.

Found: Type locality – nr. Garmish-Partenkirchen, Bavaria, GERMANY.
Other locations – Japan – Tohoko-chiho, Minamisma and Lake Inawashiro (type locality of C. inaabeus), both Fukushima Pref.;
           Experimental Pond, NEIS, Ibaraki; Shinano River, Honshu (Hirabayashi et al. 2007).
           India – Jammu & Kashmir: Kabeer colony (32.70°N, 75.00°E), Jammu; Deoli Village (32.70°N, 75.00°E).
           Israel – Mt. Hermon (33.42°N, 35.86°E).

Molecular:
MtCOI sequence from Chironomus nippodorsalis, C. dorsalis sensu Strenzke 1959 and C. alpestris is in GenBank and the BOLD databases (where all are in the same BIN, although the distance plot does suggest some specimens have a greater percentage difference).