New Chironomidae (Diptera) with elongate proboscises from the Late Jurassic of Mongolia
Author
Lukashevich, Elena D.
Author
Przhiboro, Andrey A.
text
ZooKeys
2011
130
307
322
http://dx.doi.org/10.3897/zookeys.130.1555
journal article
http://dx.doi.org/10.3897/zookeys.130.1555
1313-2970-130-307
Podonomius macromastix
sp. n.
Etymology.
From Greek
"makros"
for long and
"mastix"
for whip, after the long antenna.
Material examined.
Holotype: part and counterpart of well-preserved female PIN 4270/2314
+/-
, SW Mongolia, Shar Teg (423/6); Late Jurassic.
Diagnosis.
The new species is distinguished by its small size (wing length 1.9), well-developed elongate proboscis, strongly convex scutum with a hump, comparatively long wings with R1 with arched tip and broad cell r5, and pale legs with darker junction of femur with trochanter and tibia.
Description.
Female (Figs 1
m-n
, 2
g-h
). Measurements (mm): Total length 2.0; thorax length 0.7, height 0.9; wing length 1.9, width 0.8; abdomen length 1.1. Total length / wing length ca. 1.05. Coloration pattern as in
Podonomius blepharis
sp. n. Head 480
μm
wide, no less than 600
μm
high with proboscis, 380
μm
high to lower eye margin. Eyes large, with wide dorsomedial extension, narrowly separated by ca. 30
μm
. Facets slightly increasing to lower eye parts. Coronal triangle ca. 50
μm
high, coronal suture ca. 80
μm
high. Antenna no less than 600
μm
. Scape ca. 80
μm
, pedicel ca. 60
μm
in diameter; at least 12 flagellomeres, ca. 35
μm
wide (proximal 6 flagellomeres moniliform, 40-45
μm
long; others cylindrical, 50-70
μm
long). Clypeus ca. 130
μm
wide, ca. 150
μm
high. Proboscis well-developed, elongated, tapering, ca. 180
μm
long (about 1/3 of head height), ca. 70
μm
wide at visible apex, with pair of separate sclerotized blades. Thorax. Scutum strongly convex, with hump before midlength, 700
μm
long. Postnotum ca. 200
μm
long. Wing much longer than abdomen. Vein C only slightly produced beyond R4+5, not reaching wing tip; cell c at r-m level broader than cell r1, which is almost half as wide as cell r5 at R1 tip level; R1 with arched tip, 2/3 as long as slightly curved down distally R4+5; r-m slightly inclined, bM3+4 almost perpendicular to M. Legs poorly visible. Measurements (μm). p2(?): fe ca. 550, ti ca. 700, ta1-5 ca. 700; p3(?): ti ca. 870, ta1-5> 800. Hind femora ca. 110
μm
wide; hind tibiae 70-80
μm
wide at apex, with sclerotized apical traces, possibly of setae bases. Abdomen with three large unequal short-oval sclerotized spermathecae 60-90
μm
long, 50-60
μm
wide, with necks, in compact group. Cerci ca. 40
μm
long.
Remarks.
The new species is similar to?
Podonomius rotundatus
Kalugina, 1985 (J2, Kubekovo, South Siberia, Fig. 2i) in its venation (length of C, R1/R4+5 ratio, cells r1/r5 ratio) and size, but is distinguished by the arched tip of R1. The new species differs from
Podonomius blepharis
sp. n. in the longer wings with broader cell r5 and thoracic shape.