Spilopteron brunneum, Pham & Broad & Matsumoto & Achterberg, 2019

Pham, Nhi Thi, Broad, Gavin R., Matsumoto, Rikio & Achterberg, Cornelis Van, 2019, First records of the genus Spilopteron Townes (Hymenoptera: Ichneumonidae: Acaenitinae) from Vietnam, with descriptions of five new species, Zootaxa 4590 (1), pp. 153-165 : 154-155

Spilopteron brunneum sp. nov.

( Fig. 1 )

Material examined. Holotype: ♀ ( IEBR), Cao Bang, Phia Oac - Phia Den NP, 18–18.v.2013, Malaise trap, T.H. Pham leg.

Description of holotype female. Head. Antenna with 35 flagellomeres, first flagellomere 1.4× length of second; frons concave and polished medially, punctate laterally, carina between antennal sockets extending to face dorsally; face 0.7× as high as wide, subpolished with fine punctures laterally, medially slightly swollen and striatepunctate; clypeus about 0.4× as high as wide, subpolished, with sparse, small punctures, median tubercle small; malar space equal to basal width of mandible; exposed part of labrum about 0.4× as long as basal width; lower tooth of mandible longer than upper; inner margins of eyes divergent ventrally; diameter of lateral ocellus 0.6× ocellar-ocular distance; vertex with dense, small punctures; occipital carina evenly curved, ventrally meeting hypostomal carina about 0.7× basal mandible width from base of mandible.

Mesosoma. Epomia 0.7× basal width of mandible; pronotum with striations across median groove and dense, small punctures at dorsal posterior corner; mesoscutum 0.9× as long as wide at anterior level of tegulae, with dense punctures, pubescent; scutellum densely punctate, pubescent, lateral carina extending to apex, posterior margin with striations; metanotum polished, impunctate; mesopleuron smooth, impunctate medially, ventrally with striations and punctures, pubescent, epicnemial carina complete, sharply defined; metapleuron subpolished, with dense, small punctures, pubescent; propodeum with area basalis smooth, longer than wide, carinae medially incurved, area externa densely punctate, pubescent, area dentipara not defined and with many curved ridges posteriorly, area petiolaris polished, impunctate; fore basitarsus 3.2× second tarsomere; mid basitarsus 2.5× second tarsomere; hind leg with femur 3.7× as long as wide, 0.65× length of tibia, tarsus 0.75× tibia, basitarsus 2.5× second tarsomere, fifth tarsomere 2.3× longer than third. Fore wing length 10.4 mm, vein M&RS distad of 1 cu-a, vein 2 rs-m opposite 2 m-cu, hind wing with first abscissa of vein CU 0.6× length of vein cu-a.

Metasoma. Tergites with small punctures, pubescent; first tergite 2.9× as long as posterior width, with moderately dense punctures, lateral longitudinal carina shortly present anteriorly; second tergite 0.4× as long as first tergite, wider than long, slightly longer than third, with dense, small punctures, pubescent; sclerotized part of first sternite extending 0.9× length of first tergite; ovipositor sheath about 1.7× as long as hind tibia; hypopygium 2.6× as long as second tergite.

Colour. Black with yellow as follows: flagellomeres 11 to 22, face (except small black spot medio-dorsally), inner orbit, clypeus, mandible teeth (except distal ends), labrum, gena ventrally, scutellum, metanotum anteriorly, a small spot at distal end of first metasomal tergite, tergites 7–8, hypopygium, ovipositor, fore and mid legs, hind trochanter, hind tibia and tarsus. Hind femur reddish, posterior margin of second tergite and metasomal tergites 3–6 reddish brown. Wings with apical margin infuscate.

Male. Unknown.

Comparison. This species is most similar to Spilopteron flaviapicus Wang & Huang, 1993 in general appearance. It differs from the latter by the sculpture of the propodeum dorsally, and the colour of the propodeum, metasomal tergites and subgenital plate.

Etymology. This species is named after its largely brown metasomal tergites. Distribution. Currently known only from the holotype, collected in Phia Oac - Phia Den NP, Cao Bang Province, Vietnam.

Figures

FIGURE 1. Spilopteron brunneum sp. nov., holotype female: a. habitus, lateral view; b. face; c. dorsal view of head and mesoscutum; d. lateral view of head and mesosoma; e. dorsal view of propodeum; f. tergites.