Chironomus yoshimatsui Martin & Sublette 1972

Synoyms:  C. daitoefeus Sasa et Suzuki, 2001 (Yamamoto, unpubl.)
        C. echizensis Sasa, 1994 (Yamamoto, unpubl.)

In BOLD Bin: BOLD:AAW3949.

Adult:

Male
AR 2.85 (2.58 - 3.88) ;Wing length 3.44 (2.97-3.88) mm, VR 1.04 (1.00-1.07); LR 1.65 (1.57-1.85).
Head: Frontal tubercles 25 x 9 µm, palpal proportions (segments 2-5, units) 5 : 30 : 29 : 40.  Clypeus as wide as the antennal pedicel, with 19 setae.
Thorax with vittae most of postnotum, and mesosternum yellowish brown, dark central spot on postnotum.  Thoracic setae: acrostichal in one staggered row; dorsolateral about 24 in one to three rows;supra-alar 2; scutellar anterior row of 10 smaller setae, posterior row of 13 larger setae.
Wing with r-m slightly darkened, squama with 17 fringe setae in a partial double row.
Legs yellowish, becoming darker on the tarsi, tarsal joints one to three infuscate with a narrow apical dark band, segments four and five almost completely dark.  Foretarsus without a beard.
Leg proportions (units):

 
Fe
Ti
Ta1
Ta2
Ta3
Ta4
Ta5
LR
F/T
Ta5/Ti
PI
88
75
120
60
52
45
19
1.57-1.85
1.17
0.25
PII
89
82
49
26
19
17
10
0.57-0.64
1.08
 
PIII
100
100
73
40
30
25
10
0.63-0.75
1.00
 


From Holotype male (Martin & Sublette 1972)

Abdominal tergites II-VI with a transversely elongated central spot, that of VII merges into background.  SV of type D(d-e) of Strenzke.  IV with simple setae.


Yamaguchi City (left); Shizuoka (right).

Female:

Pupa:  Total length females 7.90-9.99 mm; males 7.99-8.66 mm.  Coloration generally darkish.
Frontal tubercles small and conical, with a subapical seta.
Base of respiratory organ 0.20 x 0.10 mm; 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 varying in number from 26-117 (mean abt 94). Posterolateral spur of segment VIII usually with a single spine, but varying up to four.
Swim fin with one dorsal and 61- 97 (mean abt 82) lateral bristles.

Fourth instar larva:  A medium sized (len. 9.8 - 15.3 mm, females (mean 12.68 mm) generally longer than males (mean 11.43 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 1.8-2.9 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 with c2 teeth well separated (type IIA), and 4th laterals not reduced (type 1).
Pecten epipharygis 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 about twice the width of the outer tooth.
Antenna 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 2.16-2.47; A2/A1 0.21-0.24; ratio of segment lengths (micron) 99 : 22 : 7 : 9 : 6; length of blade about 38-49 µm.Mandible length about 205-233 µm, third inner tooth partially separated and coloured (type I-IIB); about 11-14 grooves on outer surface at the base; Pecten mandibularis with about 10-14 bristles.
Some larvae showed abnormalities, possibly due to contamination in the habitats.

From Martin & Sublette (1972)

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).

[ Return to Index | Go to References ]


Updated: 18 April 2019
Access: Unrestricted
Copyright © 2015-2019, Jon Martin.