A review of the genus Rheotanytarsus Thienemann & Bause from China (Diptera: Chironomidae: Tanytarsini)
Author
Wang, Xinhua
Author
Guo, Yuhong
text
Zootaxa
2004
650
1
19
journal article
10.5281/zenodo.158146
7d9a2a09-d143-438c-a4ac-a4488ef61251
11755326
158146
9E918826-9476-4A0E-9528-ABAC9911BA6C
Rheotanytarsus quadratus
sp. n.
(
Figs. 10–11
)
Type
material.
Holotype
male (BDN No. 20805),
China
, Fujian Province, Nanping City, Maodi Country, Mangdangshan.
IX. 23. 2002
. Leg. Zh Liu. 1
paratype
male (BDN No. 20395),
China
, Fujian Province, Yongtai Country,
IX. 17. 2002
. Leg. Zh Liu, light trapped.
Etymology
. From Latin
quadratus
, referring to the rectangular superior volsella, which is unusual in the genus.
Diagnosis.
The species belongs to the
muscicola
group (
Saether & Kyerematen 2001
). [
Kyerematen & Andersen (2002)
used the
phaselus
group, which was an earlier division into species groups and is now included in the
muscicola
group.] The species is similar to
R. subtilis
Kyerematen & Andersen
from
Costa Rica
and
R. ramirezi
Kyerematen & Andersen
from
Mexico
, but differs from both by having a higher antennal ratio (0.7–0.8, as opposed to about 0.4), and having anal tergite bands of the V
type
as opposed to the H
type
.
FIGURES 10–13. Figs. 10–11.
Rheotanytarsus quadratus
sp. n.
Holotype, male imago: 10. Wing, 11. Hypopygium.
Figs. 12–13.
Rheotanytarsus apiculus
sp. n.
Holotype, male imago: 12. Wing, 13. Hypopygium
Male imago
(n=2)
Total length
2.20–2.40 mm
. Wing length
1.16–1.76 mm
. Total length / wing length 1.76–1.90. Wing length / profemur length 1.69–1.74. Coloration pale, eyes black.
Head.
Antenna with 13 flagellomeres. Ultimate flagellomere 328–416 µm long. AR 0.71–0.80. Temporal (n=1) 6 composed of 2 inner, 3 outer and 1 postorbitals. Clypeus with 17 setae. Tentorium 94–100 µm long, width 22 µm. Palpomere lengths (in µm): 32–40; 36; 96; 102–110; 160–190.
Wing
(
Fig. 10
). VR 1.44–1.52. Cu length 560–632 µm.
Thorax.
Acrostichals 10–16; dorsocentrals 7–10; prealars 1; scutellum with 4–5 setae.
Legs.
Spur of front tibia 16–24 µm. Spurs of middle tibia 32–36 and 27–29 µm long, and of hind tibia 34–38 and 28–30 µm long. Combs of middle leg composed of
10–12 and 8–10
free teeth, hind leg composed of 13 and 10–12 free teeth (
Table 5
):
TABLE 5.
Rheotanytarsus quadratus
sp. n.
Lengths of legs (in µm). fe ti ta1 ta2
P1 688–780 296–380 940–980 416–460 P2 640–740 440–528 280–320 120–144 P3 688–780 520–630 416–464 216–260
| ta3 ta4 |
ta5 |
LR |
| P1 304–380 256–320 |
104–120 |
2.59–3.18 |
| P2 88–112 48–64 |
40–50 |
0.61–0.64 |
| P3 200–240 120–144 |
70 |
0.74–0.80 |
Hypopygium
(
Fig. 11
). Anal tergite bands of V
type
, widely separated medially. Tergite IX with 6–8 setae. Anal point 32–34 µm long, slightly spatulate. Crests well developed, basally open and Y shaped. Phallapodeme 44–60 µm long. Transverse sternapodeme 28– 34 µm long, straight, and with oral projections. Gonocoxite 100–104 µm long. Superior volsella 22–24 µm long, squared, with 4–6 dorsal, 2 marginal setae, and 1 ventral seta. Inferior volsella 64–72 µm long. Median volsella 42–48 µm long, almost all lamellae fused into large plate. Gonostylus abruptly narrowed at apical 1/2 to rounded apex, 80–100 µm long. HR 1.04–1.25; HV 2.40–2.75.
Distribution.
The species is known from Fujian province in southern
China
(Oriental Region).