Chironomus yoshimatsui Martin & Sublette 1972

Adult:

Yamaguchi City (left); Shizuoka (right).

Pupa:  Total length females 7.90-9.99 mm; males 7.99-8.66 mm.  Coloration generally darkish.
Cephalic tubercles small and conical, with a subapical seta.
Base of respiratory organ 0.20 x 0.10 mm, HR=2; above this base is a elongate, narrow, rugose patch; anterior to the base is a smaller rugose patch.  Two Oth setae near the anterior rugose patch, four Mth setae in a longitudinal line parallel to and below the median raphe.
Recurved hooks on tergite II variable in number 94 (26-117).  Posterolateral spur of segment VIII usually with a single spine, but varying up to four.
Swim fin with one dorsal and 82 (61- 97) lateral taeniae.

According to Langton & Visser (2003) the pupa is very similar to those of C. dorsalis.

Fourth instar larva:  A medium sized (len. 12.1 (9.8 - 15.3) mm, females (mean 12.68 mm) generally longer than males (mean 11.4 (9.8-12.8) mm) bathophilus-type - however Sasa (1978) notes that one larva had small lateral tubules, so this character may be polymorphic.  Ventral tubules relatively short, posterior pair generally longer (Ant.: 0.72 (0.30-1.16) mm; Post.: 0.94 (0.48-1.36) mm.).  Anal tubules fingerlike, length about 205-280 µm and 2.2-2.9 times longer than wide; ventral pair sometimes longer than dorsal pair.
Gula and frontoclypeus darkened; frontoclypeus generally darker along the edges and the posterior end.
Mentum (Fig.c) with c2 teeth well separated (type IIA), and 4th laterals not reduced (type 1).
Pecten epipharygis (Fig.a) with about 9-19 usually fine sharp teeth (type A of Proulx et al.) unless worn.  Premandible with teeth about equal in length and inner tooth up to five times the width of the outer tooth (Ty. D).
Ventromentum (Fig.d) about 3.4 times wider than deep and about the same width as the mentum, with about 44 striae; VMR about 0.28.
Antenna (Fig.b) with A1 about 2.8-3.4 times longer than wide, Ring organ from a quarter to half way up from base of segment; AR 2.33 (2.16-2.46); A2/A1 0.21-0.24; ratio of segment lengths (micron) 99 : 22.5 : 8 : 10 : 6; length of blade about 38-49 µm.
Mandible (Fig.e) length about 205-233 µm, third inner tooth partially separated and coloured (type I-IIB); about 11-14 furrows on outer surface at the base; Pecten mandibularis with about 10-14 setae; MTR about 0.33.
Some larvae showed abnormalities, possibly due to contamination in the habitats.

Cytology:  Four polytene chromosomes with the pseudothummi-cytocomplex combination AE, BF, CD, G.  Nucleolus terminal in arm G, and in groups 18-19 in arm F.
Polymorphic in all arms.
yosA1:    1 - 2c, 10 - 12, 3 - 2d, 9 - 4, 13 - 19                                                as holomelas A1
yosA2:    1a-k, 2k-d, 9 - 4, 13a-f, 3d-i 12 - 10, 2c-a, 3a-c, 14 - 19            from holomelas A2
yosA3:    1a-k, 11d - 12, 3i-d, 13f-a, 4 - 9, 2d-k, 11c - 10, 2c-a, 3a-c, 14 - 19
yosB1:    Puff near center of arm with distal dark bands (groups 8-7)
yosB2:    Puff near center of arm with proximal dark bands (groups 7-8)
yosB3:    Small inversion of the region of the puff.
yosC1:    1 - 2g, 13e - 11d, 6e-h, 6d - 2h, 11c - 8a, 15 - 13f, 17a - 16a, 7d-a, 17b - 22
yosC2:    1 - 2g, 13e - 11d, 6e-h, 8 - 11c, 2h - 6d, 15 - 13f, 17a - 16a, 7d-a, 17b - 22
yosC3:    1a-e, 5d-6d, 6h-e, 11d-13e, 2g-1f, 5c-2h, 11c-8a, 15-13f, 17a-16a, 7d-a, 17b-22
yosD1:    1 - 6c, 13g-a, 6d - 12, 14 - 24                                                        2 inv from ST
yosD2:    1 - 6c, 13g-a, 6d - 12, 14a-c, 19 – 14d, 20 - 24
yosE1:    1 - 3e, 10b - 3f, 10c - 13
yosE2:    1 - 2, 12c - 10c, 3f - 10b, 3e-a, 12d - 13
yosF1:    1 - 2d, 9 - 2e, 10 - 23
yosF2:    1 - 2d, 16e - 10, 2e - 9, 16f - 23
yosG1:    Virtually terminal nucleolus.
yosG2:    Simple inversion from yosG1, known only as heterozygote.
yosG3:    Complex inversion, known only as heterozygote.

Molecular data
MtCOI: Japanese specimen (AB740260), and Japanese Chironomid Barcode Database.
Sequence in Genbank under the name C. flaviplumus (accession numbers JF412075 - 077).  These are very similar to those of C. sp. PK6.

Found: Japan - Type locality - Yamaguchi; Hokkaido, JAPAN (Holotype male in U.S. National Museum Collection, No. 71268, March 1970,
            H. Yoshimatsu)
            Korea - Shilim-dond, Kwanak-gu, Seoul and numerous other localities (as C. flaviplumus, Ree & Kim 1981).
            Russia: Sakhalin Island; nr. Vladivostok (Kiknadze et al. 2003).

Adults redescribed by Ree & Kim (1981) under the name C. flaviplumus.  Karyotype redescribed by Kiknadze et al. (2003).
Langton & Visser (2003) list this species as a synonym of C. dorsalis on the basis of pupal similarity, but the cytology and BARCODE data clearly show that this is incorrect.