Kribiodorum Kieffer (= Stelechomyia Reiss) (Diptera: Chironomidae) extends into the Oriental region: three new species and expanded diagnoses
Author
Cranston, Peter S.
text
Zootaxa
2018
2018-10-01
4486
4
535
547
journal article
29360
10.11646/zootaxa.4486.4.7
de8bae68-74a9-45df-ba8b-aa6c8673f24f
1175-5326
1442332
9503B15D-3126-43E4-BDA0-E66465227BC8
Kribiodorum
Kieffer
Kribiodorum
Kieffer, 1921
: 270
.
Stelechomyia
Reiss, 1982
: 294
. Type-species
Chironomus perpulcher
Mitchell
(orig.des.)
Included species:
Kribiodorum pulchrum
Kieffer, 1921
;
Kribiodorum perpulchrum
(
Mitchell, 1908
)
;
Kribiodorum belalong
Cranston
sp. n.
Brunei,
Kribiodorum malicky
Cranston
sp.n.
Thailand and
Kribiodorum kunene
Cranston and Harrison
sp. n.
Namibia.
Generic diagnosis. Male
as in
Reiss (1982)
and
Cranston
et al
. (1989)
extended and including the following:
Body length
2.6–5.5 mm
, wing length
1.35–1.86 mm
. Legs dark banded, wing iridescent, brown with variably interrupted transverse translucent patches (
Fig. 1C–D
).
Antenna. With 13 flagellomeres, A.R. 0.7–1.7.
Head. Eye bare with wedge-shaped or quadrate dorsomedial extension. Frontal tubercles absent. Palp 5– segmented, segment 2 almost globular, segment 3 with 0–2 sensilla not in pit.
Thorax. Antepronotal lobes narrowed dorsally and narrowly or more distinctly separated dorsomedially; scutum extended, overreaching antepronotum(
Fig. 1A–B
). Without tubercle. Acrostichals present but numbers uncertain (see comments), dorsocentrals uniserial, up to 12 including
1–2 in
humeral position, 3–6 prealars, 3–7 scutellars.
Wing (
Fig. 1C–D
) iridescent, brown with pale patches. Membrane finely punctate, without macrosetae. Anal lobe slight.
Costa
non-extended, ending above M1+2. R1 and R4+5 well separated with R2+3 running between and ending midway between apices of R1 and R4+5. R4+5 terminating slightly proximal to wing apex. V.R. c. 1.2–1.3.
Veins R
, R1 and R4+5 setose. Squama bare.
All legs with some darker pigmented bands, setae arising from these areas contrastingly darker than from pale cuticle. Fore-femur weakly to strongly dilate in distal 1/3, dark with dense dark setae. Variable patterns of dark and pale bands on all femora and tibiae (
Fig. 1H–L
), with some darkening on distal tarsomeres, perhaps faint or absent on short mid-leg tarsomeres. Fore-tibial apex with shallow rounded scale and long curved spur inserted subapically on scale (
Fig. 1E, F
), mid- and hind-tibial combs narrowly separated; shorter, higher comb with distinct spur, broader shallower comb without spur (
Fig. 1G
). LR1 2.0. Pulvilli slender, short, not extending beyond apex of simple claw.
Abdomen with dense long setae.
Hypopygium (
Figs. 1M
,
2A–I
) with strong anal tergite bands, extending near to base of anal point, not meeting, enclosing field of dense long setae. Anal tergite squared off posteriorly, bearing subterminal anal point varying from long slender and tapering to broad and distally curved downward, with lateral flanges. Superior volsella (
Fig. 2E–I
) comprising raised base with few long setae and distal digitus, either a hyaline lobe or narrower and tapering to point. Mediolateral, in ventral plane at base of superior volsella a pad bearing 4–5 long, mediallydirected strong setae, represents a squat median volsella. Inferior volsella elongate, not fused to gonocoxite other than narrow base. Gonocoxite and gonostylus conventional, with microtrichia and long setae.
Female,
based on 2 species only; as diagnosis above excepting dimorphism.
Head. Antenna with 6 flagellomeres (division between 1
st and
2nd can be faint) with paired hyaline sensilla located opposite and subapical on flagellomeres 2–6; terminal flagellomere dark (
Fig. 3A
). Palp with very short segment 2, distally of increasing length; segment 3 subapically with short single, perhaps double small sensillum. Clypeals numerous and strong, few linear aligned verticals.
Thorax with small, dorsally fused antepronotal lobes; scutum narrowed anteriorly, extending beyond antepronotum. Acrostichals not visible, few Dc (5–8) with anteriormost in humeral position; few prealars (2–4) and scutellars (2–3).
Wing (
Fig. 2C
) length
1.45–1.8mm
, with dark pigment deeper and slightly more extensive than in male.
Legs as male, but the less dilate fore-femur all are depilate, thus length, strength and pigmentation of setae is not discernible. LR1 2.4. Pulvilli slightly shorter than claw.
Genitalia (
Fig. 3B, C, D
). Notum long, thin, with short rami. Gonocoxapodemes gently curved not fused medially, each with apparent weak branch into gonapophysis VIII. Coxosternapodeme strongly sclerotized, weakly curved. Gonapophysis VIII (
Fig. 3C
) with elongate dorsomesal lobe, essentially continuous with inner contour of vagina, microtrichiose, hyaline apico-medially, and distinct ventrolateral lobe of similar size to dorsomesal lobe, lying lateral to, and separate to dorsomesal lobe, microtrichiose with many short simple medio-apically directed setae. Apodeme lobe not visible. Labia well developed, hyaline, without microtrichia. Gonocoxite IX small, not extended laterally. Tergite IX broad, densely setose, undivided. Postgenital plate not visible. Seminal capsule midbrown, ovoid to near spherical, with weak neck; spermathecal duct straight, thick-walled, dilate prior to fusion at apparent common opening. Cerci large, quadrate.
Pupa
as in
Pinder & Reiss (1986)
Larva
as in
Pinder & Reiss (1983)
and
Epler
et al
. (2013)