A new genus and species of Acaenitini ( Hymenoptera , Ichneumonidae , Acaenitinae ) from China

Dentifemura Sheng & Sun, gen. n. and Dentifemura maculata Sheng & Sun, sp. n. belonging to tribe Acaenitini of subfamily Acaenitinae (Hymenoptera: Ichneumonidae), collected from Jiangxi Province, China, are described.

Th e morphological terminology is mostly that of Gauld (1991).Wing vein nomenclature is based on Ross (1936) and the terminology on Mason (1986Mason ( , 1990)).Etymology.Th e name of the new genus is based on the large tooth on the ventral side of the hind femur.Th e gender is feminine.

Dentifemura
Description.Fore wing length 9.6 to 10.5 mm.Clypeal suture very weak.Clypeus fl at, apical median portion concave, apical margin thin.Lower tooth of mandible as long as or slightly longer than upper tooth.Labrum crescentic, 0.4 to 0.5 as long as wide.Maxillary palps with evenly distributed hairs.Th ird segment of maxillary palp gradually expanded apically, its apical truncation strongly oblique (Figure 3).Malar space distinctly longer than basal width of mandible.Pedicel relatively long, shortest side approximately as long as widest diameter.Occipital carina complete.Without epomia.Areolet absent.Fore wing vein 2rs-m basad of 2m-cu.Ventral profi le of hind femur with a strong blunt tooth on hind 0.25.Inner sides of front and middle claws with acute accessory tooth.Hind claws simple.Propodeum evenly sloping from anterior transverse carina to apex, without posterior transverse carina.First tergum evenly and slightly narrowed toward base.First sternite evenly convex sub-basally, with a few erect hairs.Ovipositor sheath about 0.33 times as long as fore wing.
Remarks.Th is new genus is similar to Jezarotes Uchida and Ishigakia Uchida and can be distinguished from Jezarotes in lacking a subapical, strong transverse ridge on the clypeus; the upper tooth of the mandible as long as or slightly shorter than the lower tooth; the median lobe of the mesoscutum is vertical in front; and fore wing vein 2rs-m is basad of 2m-cu.In Jezarotes, the clypeus has a strong, transverse subapical ridge; the upper tooth of the mandible is very small; the median lobe of the mesoscutum strongly projects forward; and fore wing vein 2rs-m is distad of 2m-cu.Th e new genus can be distinguished from Ishigakia by the position of fore wing vein 2rs-m (basad of vein 2m-cu in Dentifemura gen.n., far distad in Ishigakia) and the presence of a conspicuous ventral tooth on the hind femur in Dentifemura gen.n.
In Townes's (1971) key to genera, the new genus can be inserted as follows: 5.
Clypeus without a transverse ridge or carina next to apex, its apical half rather fl at and apical margin thin.Description.Female.Body length 10.2 to 11.5 mm.Fore wing length 9.6 to 10.5 mm.Ovipositor length 3.3 to 3.5 mm.
Head.Face 1.5 to 1.7 times as wide as long, with dense punctures (Figure 2), median portion convex, upper portion with a median longitudinal carina, reaching to middle ocellus.Clypeal foveae circular.Clypeal suture vestigial between clypeal foveae.Clypeus nearly fl at, basal portion with punctures sparser than on face, apical portion smooth and impunctate, apical median portion narrowly concave, apical margin thin.Labrum crescentic, 0.42 to 0.45 as long as wide.Mandible with fi ne and dense longitudinal lines and unclear fi ne punctures, lower tooth slightly longer than upper tooth.Cheek with punctures sparser than on face.Malar space 1.18 to 1.23 times as long as basal width of mandible.Subocular sulcus distinct.Gena glossy, with distinct punctures, but gradually fi ner and more sparsely punctate towards upper portion, in lateral view approximately 0.7 times as long as width of eye, evenly convergent backward.Vertex (Figure 4) with punctures.Lateral margin of lateral ocellus concave.Interocellar area with fi ne and indistinct punctures.Postero-ocellar line approximately as long as  Mesosoma.Pronotum glossy, anterior portion with sparse punctures, apical margin slightly protruding and longitudinally ridge-shaped, laterally concave with distinct transverse wrinkles, upper posterior portion with distinct punctures, distance between punctures 0.2 to 0.5 times diameter of puncture.Without epomia.Mesoscutum with dense punctures (Figure 5), front portion of median lobe vertical, posterior portion with a short median longitudinal carina.Notaulus very strong, almost reaching to posterior margin of mesoscutum.Scutoscutellar groove with longitudinal wrinkles.Scutellum weakly convex, with sparse and fi ne punctures, distance between punctures 0.5 to 2.0 times diameter of puncture.Postscutellum smooth, evenly oblique posteriorly, anterior-lateral portion deeply concave.Upper portion of mesopleuron including speculum smooth; lower portion, anterior portion and subtegular ridge with dense and distinct punctures.Without mesopleural fovea.Prepectal carina strong, upper end reaching to mid-height of front margin of mesopleuron.Mesosternum with dense punctures, but comparatively fi ner than on mesopleuron.Metapleuron smooth, with sparse and fi ne punctures, distance between punctures 1.0 to 2.0 times diameter of puncture.Juxtacoxal carina absent.Submetapleural carina complete.Wing brownish hyaline.Fore wing vein 1cu-a basad of 1-M, distance between them about 0.3 to 0.4 times length of 1cu-a.Areolet absent.Vein 2rs-m basad of 2m-cu, distance between them approximately as long as or slightly longer than width of vein.Vein 2-Cu approximately as long as 2cu-a.Hind wing vein 1-cu slightly shorter than cu-a.Legs stout.Ventral profi le of hind femur with a strong blunt tooth on hind 0.25.Fourth segment of tarsus very short, in lateral view of hind tarsi, ratio of length of tarsomere 1:2:3:4:5 is 12.0:4.3:4.0:3.0:9.0.Inner sides of front and middle claws with an acute accessory tooth.Hind claws simple.Propodeum (Figure 6) with distinct punctures except apico-median portion polished, with distinct anterior transverse carina, lateral carina of area basalis and lateral longitudinal carina.Area basalis wider than long.Propodeal spiracle obliquely elliptical, approximately 1.6 times as long as maximum width.
Metasoma.First tergum 1.9 to 2.0 times as long as apical width, evenly and slightly narrowed toward base, with sparse and fi ne punctures.Median dorsal carina slightly longer than sternite.Dorsolateral carinae indistinct.Ventrolateral carinae complete.Spiracle transversely elliptical, located slightly anterior of middle.Second and following terga with very sparse and fi ne punctures, gradually weaker and indistinct.Second tergum approximately 0.5 times as long as apical width.Fourth to sixth terga expanded.Posterior median portions of sixth and seventh terga weakly sclerotized.Apex of hypopygium reaching to or slightly projecting beyond tip of metasoma.Cercus almost reaching to tip of eighth tergum.Ovipositor sheath 1.1 to 1.2 times as long as hind tibia.Ovipositor slightly compressed, apical portion with 4 weak and unclear teeth.
Colour (Figure 1).Yellowish brown.Antenna dark brown, scape and dorsal profi le of pedicel blackish brown.Dorsal and ventral profi les of front and middle femora and tibiae and tarsi more or less dark brown.Apical portions of front and middle femora, longitudinal line on dorsal profi le of hind coxa and small fl eck on ventral profi le, basal portions of trochanters, basal portion of hind femur and two longitudinal lines on dorsal and ventral profi les brownish black.Hind tibia reddish brown, tarsus dark brown.Median portion of occipital carina, longitudinal fl ecks on median and lateral lobes of mesoscutum, scutoscutellar groove, basal margin of propodeum, oblique longitudinal fl eck of fi rst tergum and basal transverse bands of second and third terga black.Apical margin of third tergum, basal and apical median portion of fourth to sixth terga, and median transverse band of seventh tergum dark brown.Fore wing with stigma brown, veins brownish black.
Remarks.Dentifemura can be recognised by the following combination of characters.Th e clypeus lacks a transverse ridge or carina next to the apex.Th e lower tooth of the mandible is slightly longer than the upper tooth.Th e malar space is about 1.2 times as long as the basal width of the mandible.Th e third segment of the maxillary palp is gradually expanded apically, its apical truncation strongly oblique.Fore wing vein 2rs-m is basad of 2m-cu.In ventral profi le, the hind femur has a strong, blunt tooth on the hind 0.25.Th e fourth tarsomere is very short.On the propodeum, only the anterior transverse carina, the lateral carina of the area basalis and the lateral longitudinal carina are distinct. Biology.Unknown.