Chelonus subcontractus
authorAbdinbekova, 1971
synonyms
body
shape4mm [Ab2]. ♀ ♂: 2.4 - 3(-4) mm [P6]. 3.0 - 4.0mm [T14]. 2.4 mm [By1].
colorBody black, covered with short sparse hairs, densely rugose, dull, matte [Ab2]. The body is black, evenly and not roughly rugose-punctured, matte or slightly shiny [T14].
head
shapeThe head is noticeably wider than the mesosoma, roundly narrowed behind the eyes, slightly more than twice as wide as long; occiput strongly carved, temples almost half as long as eye width; ocelli in an obtuse-angled triangle, the base of which is noticeably less to almost equal to the distance from it to the eye; POL 3-4 times OD; longitudinal diameter of eye twice as long as transverse, almost 2.5 times as long as malar space; height of face half its width, noticeably larger than height of clypeus; clypeus 1.5 times wider than high; distance between tentorial fossae slightly greater than distance from fossa to eye, slightly greater than clypeus height; the proboscis is undeveloped; maxillary palps shorter than head height [Ab2]. Temple in dorsal view relatively strongly rounded (Fig. 3) [P4]. Longitudinal eye diameter 2.5 times longer than gena height. Head 1.1 times as wide as mesonotum. [T11]. Head in dorsal view 2.1-2.2 times as broad as long, temple (Fig. 1) rounded to strongly rounded (less frequently constricted), one-fourth shorter than eye and occiput deeply excavated [P6]. The head is slightly wider than the chest, roundly narrowed behind the eyes, its width is approximately twice its length. The temples are half as long as the transverse diameter of the eye. Width of ocellar triangle nearly equal to OOL; POL 2.5 times eye diameter. The longitudinal diameter of the eye is twice the transverse diameter, 2.5-3 times the height of the cheek. The width of the face is almost twice its height. [T14]. Head transverse, narrowed towards the back, relative proportions of length: width: height like 20: 42: 37; shorter diameter of the eyes as long as the width of the temples; Malar space 2.5 times as long as the base of the mandible; Eyes ovate, longer than wide (21:13); Ocelli small and OOL 1.8 times as long as POL; Rostrum invisible [By1].
sculptureClypeus densely but finely punctate, slightly shining; occiput weakly transversely rugose [Ab2]. The face, vertex and temples are gently rugose-punctured, without pronounced transverse rugae. Head with granular sculpture, vertex behind ocelli with small transverse rugae [T14]. Face punctate and matt; Clypeus more finely punctate and shiny; temples with horizontal rugae [By1].
colorPalpi brownish yellow [Ab2].
antenna
shape ♀Antennae slightly longer than head and mesosoma, thin, filiform; 3rd segment 1.5 times as long as scapus, almost 1.5 times as long as the 4th; segments of flagellum gradually shortening from base to apex, at apex length 1.5 times width [Ab2]. Apical flagellomeres slightly longer than wide, others less than two times longer, and basal ones usually as maximum 2-3 times longer, than wide [T11]. Antennal segments long, third segment 2.8 - 3 times (♀) or three times (♂) and penultimate segment 1.25 - 1.3 times (♀) or 1.5 - 1.8 (2) times (♂) as long as broad apically [P6]. Antennae slightly longer than the head and mesosoma taken together, the length of the 3rd antennal segment is 2.5-3.0 times its width, the segments in its apical part are equal to or slightly longer than their width [T14]. Mid-antennal segments 1.5 times as long as wide [T4]. Antennae shorter than the body (47: 68); Scapus 2 times as long as it is wide; 3rd segment 3 times as long as it is wide; the following segments gradually becoming shorter; penultimate segment only slightly longer than wide (41: 39) [By1].
shape ♂
colorAntennae usually entirely black [T4].
mesosoma
shapeThe mesosoma is one third longer than its height; notauli unclear; propodeum abrupt posteriorly, with weak transverse carina and two small teeth laterally [Ab2]. Mesosoma length 1.3–1.4 times its height. Propodeum without transverse carina or very weakly expressed [T14]. Mesosoma short, relative proportions of length: width: height as 50: 35: 33; Notauli invisible; Prescutellar furrow simple. Propodeum with lateral teeth [By1]. Length of mesosoma 1.3 times height [T23].
sculptureScutellum densely but finely punctate, slightly shining [Ab2]. Mesonotum in front of scutellum with finely meshed sculpture in combination with short longitudinal rugae [T14]. Scutellum finely carved and roughly notched at the base. Mesosoma sculpted everywhere, but in the middle of the mesonotum reticular and more coarsely rugose [By1].
color
legs
shapeHind femora 4 times as long as wide; large spur of hind tibia slightly longer than 1/3 of metatars; 5th segment of hind tarsus equal to 3rd, less than 2nd [Ab2]. Inner spur of hind tibia somewhat more than half as long as basitarsus [P6]. Hind femur 3–3.5 times as long as wide [T14]. Legs fine, relative length ratios of the rear coxa: trochanter: femur: tibia: tarsus as 17: 9: 33: 36: 36; Hind femur 3.6 times as long as wide; Hind tibial spurs as long as the 2nd tarsal segment and longer than the fourth (5: 4) [By1].
sculptureHind coxae densely rugose, slightly shiny [Ab2].
colorApices of femora, tibia and tarsus of fore legs, tibia and tarsus of middle legs, main half of tibia and tarsus of hind legs brownish yellow [Ab2]. Legs (at least hind femora) black or dark-brown. Hind tibiae dark-colored, occasionally yellowish-brown at base but without pronounced yellowish constriction [T11]. Legs mostly dark-colored, hind tibiae with yellowish band [T14].
wings
shapeVein 1-R1 is approximately half as long as the pterostigma; 3-SR equal to r, 3 times shorter than SR1, 2.5 times shorter than 2-SR; 1-CU1 = 0.5 times 2-CU1 (Fig. 6) [Ab2]. Vein r about as long as or somewhat longer than 3-SR; 1-R1 less than half as long as pterostigma (Fig. 4) [P4]. Strongly shortened radial cell of fore wing;1-R1 rarely 2 times, more often 1.5 times, shorter than pterostigma. Marginal cell 1.5-2 times larger than 2nd submarginal cell. [T11]. Marginal cell along metacarp 0.5-0.6 times as long as pterostigma, r usually shorter than (to at most as long as) 3-SR (fig. 2) [P6]. 1-R1 0.5–0.7 times as long as pterostigma [T14]. Fore wings (fig. 8) shorter than the body (51: 60); R ends well before the wing tip; r arising behind the middle of the pterostigma, shorter than the width of the pterostigma (5: 9) and 1.6 times as long as 3-SR; SR1 thickened at the base and 5 times as long as 2-SR [By1].
colorThe wings are darkened, the pterostigma and veins are brown, the veins at the base of the wing are yellow [Ab2]. Tegulae black [T4]. ♂ wings weakly but distinctly darkened [T4]. Wings light, pterostigma and veins brown [By1].
metasoma
shapeMetasoma slightly shorter than head and mesosoma, slightly curved posteriorly, oval: its length is half [twice?] its width in middle part, almost three times its height in apical third; the length of the ventral cavity of the carapace is 6/7 of the length of the metasoma [Ab2]. Carapace in lateral view more convex or posteriorly higher than anteriorly (Fig. 5). Carapace reflexed apically by 0.1 its length and regularly rounded. Metasoma 1.5-1.65 times longer than wide [P4]. Mesosoma in lateral view 1.4-1.5(-1.6) times as long as high (♀ ♂) [P6, key] [fig 5: 3.0 times]. Metasoma oval, apically slightly bent forward, 1.5-1.6 times as long as wide [T14]. Metasoma (fig. 9) longer than the mesosoma (31:25), egg-shaped [By1].
sculptureMetasoma with longitudinal rugae at the base [Ab2]. Longitudinal rugae abundant and weakly raised, occasionally almost undeveloped. Metasoma with longitudinal rugae only reaching its middle part. [T11]. Metasoma in basal half with more or less sinuous longitudinal rugae [T14]. Metasoma mildly sculptured, with weak longitudinal rugae only at base [T4]. Metasoma irregularly longitudinally rugose [By1]. Metasoma with weak longitudinal rugae not extending beyond its middle [T23].
colorCarapace basally either fully black or (sometimes) with a pair of lateral yellow spots [P4]. metasoma at base with two lateral yellow spots [T4].
♀ ovipositorOvipositor weakly protrudes [T14]. The ovipositor protrudes a little from under the carapace [Ab2].
♂ apertureThe aperture is small, about 1/3 of the width of the carapace, slightly transverse [Ab2]. The aperture is located almost in the middle of the posterior surface of the metasoma [T14]. Aperture on apex of metasoma large, its width a few times greater than length of apical segment of hind tarsus [T4].
other info
distributionDE, FR, NL, PL [FE].
remarksThe two species [depressus and subcontractus] are quite similar and they seem to be very closely related to each other [P4]. Close to Chelonus сontractus Nees, from which it differs in a short marginal cell, which is half the length of the pterostigma [Ab2].
hostsM. subcontractus was noticed parasitizing on fall webworm [Hyphantria cunea] (Tobias, 1990).
