Chelonus larsi
authorKittel, 2016
synonymsMicrochelonus fischeri (Tobias 1994)
body
shapeBody 2.7 - 3.7 mm, ♂ 3 - 3 . 5 mm [T1]
colorBody black [T1]
head
shapeHead behind eye rounded, about temples slightly narrower than about eyes, 1.1 times broader than mesonotum, 1.9 times as broad as long, 1.2 times as broad as high. In dorsal view eye 1.4 times longer than temple. Ocellar triangle one ocellus diameter longer than OOL. Distance between hind ocelli twice the diameter of an ocellus. Eye in lateral view 1.7 times as long as wide, 3 times as long as malar space. Face 2.3 times as wide as high, the same width as longitudinal diameter of eye. Maxillar palpi as long as height of face with clypeus [T1][T14].
sculptureHead not roughly sculptured, faintly shiny. Vertex behind ocelli and temple transversally striato-rugulose, face irregularly rugulose to vertically (near eyes) or concentric rugulose. Clypeus punctate, shining [T1]
colorApical part of mandibula yellow-brown [T1]
antenna
shape ♀Antenna as long as head and mesosoma together. Third segment 2.5 times as long as broad, fourth segment twice as long as broad, 12-15th segments as long as broad. Segments of apical part of antenna sometimes with dents [T1][T14].
shape ♂Antennae with 19 segments. Preapical segments of flagellum as long as broad or its length a little more than width [T1]
color
mesosoma
shapeMesosoma 1.5 times as long as high. Propodeum with clear transverse keel and a pair of rounded tubercles laterally [T1]
sculptureMesosoma rather roughly sculptured, but mesonotum sometimes with extremely smooth sculpture, shining, often less smooth. Front of scutellum longitudinally rugose. Middle part of scutellum punctate, shining, scutellum sometimes rugoso-punctate [T1][T14]
color
legs
shapeHind femur 3 times as long as broad, fifth segment of hind tarsus longer than third, but shorter than second segment [T1]
sculpture
colorFore tibia yellow-brown [T1]
wings
shapePterostigma as long as or a little longer than 1-R1, 3-SR a little shorter to a little longer than r, 3-SR 4 - 5 times shorter than SR1, 1.6 - 2 times as long as r-m. The marginal cell of the fore wing is 2.5–3 times larger than the 2nd submarginal cell [T14].
colorWings infuriate [sic]. Pterostigma and veins brown, mediocubital and basal veins light-brown.
metasoma
shape♀ Carapace oval, apically incurved ventrally on 0.1 its length, 1.75 times as long as broad, 3.2 times as long as maximum height. ♂ 1.75 - 2 times as long as broad [T1]
sculptureCarapace longitudinally rugulose, on basal part rugulo-rugose, on apical part striato-rugulose [T1]
color
♀ ovipositorOvipositor short [T1]
♂ apertureApical aperture disposed on lower half of carapace, oval, 0.25 - 0.33 as broad as carapace, about 2 times as broad as high. Middle tubercle of apical aperture a little longer than its height, about 0.3 height of aperture [T1][T14]
other info
distribution
remarksDifferential diagnosis. Microchelonus fischeri sp.n. [larsi] is related to M. contractus (Nees); differs by smoother sculpture of mesonotum combined with reticulate-rugose sculpture in front of scutellum and dark color without medial yellow band on hind tibia. Because of the infumate wings M. fischeri [larsi] is similar to M. scabrosus (SZEPLIGETI); but differs by smoother sculpture of mesonotum and small oval apical aperture of male (aperture of M. scabrosus is very wide - several times as wide as high) [T1]
hosts
type description
Microchelonus fischeri sp.n.
(figs. 1 - 4)
Holotype: ♂, Austria inf., Klippe Ruine Staatz, 6.7.83, leg. Fischer (in collection NMV). Paratypes: Hungary: 1 ♂, Bukk hgs., Létrâs tetó, 1966.VII.13, leg. Móczar L.; 1 ♀, Matra, Galyatetó, 1952.VI.25, leg. Sólymosné; 1 ♀, Bajânsenye Csertaerdö, 1980.VII.9, leg. Podlussâny (in collection of Hungar. Nat. Hist. Mus., Budapest). Finnland: 2 ♂♂, U. Helsinki, 6880:390, 23.7.1976, M. Koponene leg.; 1 ♂, EH. Hattula, 6775:356, 11.7.1976, M. Koponen leg.; 1 ♂, V. Nauvo Sell, 699:22, 18.7.1978, M. Koponen leg. (in collection of Dept. Agric. and Forest Zool. of University Helsiniki, partly in Zool. Inst. Russian Acad. Sci.). Lituania: 1 ♂, Rojus-2, 1972.VI.20, V. Jonaitis. Russia: 2 ♂♂, Karelia, Kizhi, 24.VII. 1962, V. Trjapitzin leg. (in collection of Zool. Inst. Russian Acad. Sci., St. Petersburg).
Description. Holotype (♂) [wa: ♀ ?]. Body 3.5 mm. Head behind eye rounded, about temples slightly narrower than about eyes, 1.1 times broader than mesonotum, 1.9 times as broad as long, 1.2 times as broad as high. In dorsal view eye 1.4 times longer than temple. Ocellar triangle on diameter ocellus longer than OOL. Distance between hind oecelli twice longer diameter of an ocellus. Eye in lateral view 1.7 times as long as wide, 3 times as long as malar space. Face 2.3 times as wide as high, the same width as longitudinal diameter of eye. Maxillar palpi as long as height of face with clypeus.
Antenna as long as head and mesosoma together. First flagellar joint 2.5 times as long as broad, second joint twice as long as broad, 12-15th joints as long as broad, without dents. Mesosoma 1.5 times as long as high. Propodeum with clear transverse keel and a pair of rounded tubercles laterally. Pterostigma as long as radial cell along metacarp, r2 as long as r1 , 4.5 times as long as r3 [?], 1.8 times as rm1. Hind femur 3 times as long as broad, fifth joint of hind tarsus longer than third, but shorter than second joint. Carapace oval, apically incurved ventrally on 0.1 its length, 1.75 times as long as broad, 3.2 times as long as maximum height. Ovipositor short.
Head not roughly sculptured, faintly shiny. Vertex behind ocelli and temple transversally striato-rugulose, face irregularly rugulose. Clypeus punctate, shining. Mesosoma rather roughly sculptured, but mesonotum with extremely smooth sculpture, shining, front of scutellum longitudinally rugose. Middle part of scutellum punctate, shining. Carapace longitudinally rugulose, on basal part rugulo-rugose, on apical part striato-rugulose.
Body black. Apical part of mandibula and first tibia yellow-brown. Wings infuriate. Pterostigma and veins brown, mediocubital and basal veins light-brown.
Variability of paratypes. Body 2.7 - 3.7 mm. Radial cell along metacarp sometimes a little shorter than pterostigma, r2 a little shorter or longer than r1 , 4-5 times as long as r3, 1.6-2 times as long as rm1.
Joints of apical part of antenna sometimes with dents. Sculpture of mesonotum often less smooth, scutellum sometimes rugoso-punctate. Face often vertically (near eyes) or concentric rugulose.
Male. Body 3 - 3 . 5 mm. Antennae with 19 joints. Preapical joints of flagellum as long as broad or its length a little more than width. Carapace 1.75 - 2 times as long as broad. Apical aperture disposed on lower half of carapace, oval, 0.25 - 0.33 as broad as carapace, about 2 times as broad as high. Middle tuberale of apical aperture a little longer than its height, about 0.3 height of aperture.
Differential diagnosis. Microchelonus fischeri sp.n. is related to M. contractus (NEES); differs by smoother sculpture of mesonotum combined with reticulate-rugose sculpture in front of scutellum and dark colored without medial yellow band on hind tibia. Because of the infumate wings M. fischeri is similar to M. scabrosus (SZEPLIGETI); but differs by smoother sculpture of mesonotum and small oval apical aperture of male (aperture of M. scabrosus is very wide - several times as wide as high).
Data used in the multi-access key
These data are collected from the species descriptions and redescriptions, from published figures and photographs and from own measureements and observations. For a description of the different variables and value classes see this
pdf.
| morphology |
| basic information | female | male |
| body length (mm): | (2.7) 2.7 - 3.5 (3.7) | (2.7) 2.7 - 3.5 (3.7) |
| number of antennal segments: | 16 | 19 |
| head, dorsal view |
| Head width : length | wide | wide |
| Temples narrowing - widening | narrowing | narrowing |
| Eye length : temple length | > 1.25 | > 1.25 |
| Roundness temple | medium, weak | medium, weak |
| POL : OD | <= 2, 2 - 3 | <= 2, 2 - 3 |
| Ocellar triangle shape | very narrow, narrow | very narrow, narrow |
| Excavation of head | 15 - 25% | 15 - 25% |
| head, lateral view |
| Head height : length | --- | --- |
| Eye height : length | very short, short | very short, short |
| Temple length : eye length | --- | --- |
| head, frontal view |
| Head width : height | very narrow, narrow | very narrow, narrow |
| Face width : height | very wide | very wide |
| Eyes converging ventrally | --- | --- |
| EH : MSL | --- | --- |
| Clypeus width : height | --- | --- |
| Clypeus extending above bottom of eyes | --- | --- |
| Tentorial pits | --- | --- |
| Shape of lower margin clypeus | --- | --- |
| antennae |
| Antennal shape | --- | filiform, not widened |
| Segment 3 length : width | short, medium | --- |
| Penultimate segment length : width | short | short |
| Length of antenna : length of body | 2: short | --- |
| mesosoma, lateral view |
| Length : height | medium | medium |
| transverse carina | well developed | well developed |
| lateral teeth | weak, small, short, present | weak, small, short, present |
| mesosoma, ventral view |
| Prepectal carina lamelliform | indistinct | indistinct |
| legs |
| Hind femur length : width ratio | short | short |
| Hind tibia length : hind tarsus length ratio | --- | --- |
| Hind tibia (longest) spur length : metatars length ratio | | |
| wings |
| Vein 1-R1 length : pterostigma length | long | long |
| Vein r length : vein 3-SR length | short | short |
| Shape vein SR1 (straight / concave / convex) | | |
| S-shape vein SR1 | --- | --- |
| cell M : cell Sm2 | Sm2 small | Sm2 small |
| Pterostigma length : width ratio | --- | --- |
| Angle between radial vein (r) : vein 1-R1 | --- | --- |
| metasoma, dorsal view |
| Length : width ratio of metasoma | short, medium | short, medium |
| Shape of metasoma | widest in middle | widest in middle |
| metasoma, lateral view |
| Length : height ratio of metasoma | medium | medium |
| posterior : anterior height ratio of metasoma | small, medium | small, medium |
| Position of maximum height | medium-posterior, posterior | posterior |
| metasoma, ventral view |
| Metasoma posteriorly curved forwards | just/slightly incurved | just/slightly incurved |
| male apical aperture |
| Aperture width : metasoma width | no aperture | small, medium |
| Aperture shape | n. a. | (nearly) round, oval |
| Median process shape | n. a. | vertical carina, horizontal, nearly round |
| sculpture |
| head |
| general coarseness | fine | fine |
| clypeus |
| coarseness punctation | punctate | punctate |
| density punctation | --- | --- |
| face |
| sculpture type | rugose | rugose |
| sculpture direction | irregular, transverse-longitudinal, diagonal/concentric | irregular, transverse-longitudinal, diagonal/concentric |
| vertex and temple |
| sculpture type | striate-rugulose | striate-rugulose |
| mesonotum |
| sculpture type | notauli slightly distinct | notauli slightly distinct |
| scutellum |
| middle | punctate | punctate |
| lateral | punctate, rugose / striate | punctate, rugose / striate |
| metasoma |
| base - mid sculpture | longitudinally rugose / rugose-striate | longitudinally rugose / rugose-striate |
| sculpture at apex | rugulose | rugulose |
| coarse / fine boundary | mid (50 - 70%) | mid (50 - 70%) |
| color |
| head |
| mandibles color pattern | light tip | light tip |
| palpi, lightest color | --- | --- |
| antennae |
| scapus, lightest color | black, dark brown | black, dark brown |
| segment 3 and 4, lightest color | black, dark brown | black, dark brown |
| legs |
| fore coxae lightest colour | dark | dark |
| fore femur lightest colour | --- | --- |
| fore femur color pattern | --- | --- |
| hind femur lightest colour | dark | dark |
| hind femur color pattern | entirely dark | entirely dark |
| hind tibia lightest colour | dark | dark |
| hind tibia color pattern | entirely dark | entirely dark |
| hind basitarsus lightest colour | dark | dark |
| hind tarsus segment 2-3 lightest colour | dark | dark |
| wings |
| middle veins lightest colour | medium dark | medium dark |
| basal veins lightest colour | medium light | medium light |
| metasoma |
| metasoma colour pattern | entirely dark | entirely dark |
| metasoma lightest colour | dark | dark |
| metasoma base, colour pattern | entirely dark | entirely dark |
| metasoma base, light spots | n.a. | n.a. |
| metasoma base, light band | n.a. | n.a. |
Chelonus larsi in published keys
T14: Tobias, 2010
Palearctic species of Microchelonus Szépligeti (Hymenoptera: Braconidae, Cheloninae): key to species.
