Triancyra cucphuongensis, Pham & Broad & Zhu & Achterberg, 2018

Pham, Nhi Thi, Broad, Gavin R., Zhu, Chao-Dong & Achterberg, Cornelis Van, 2018, A review of the genus Triancyra Baltazar (Ichneumonidae: Rhyssinae) from Vietnam, with descriptions of three new species, Zootaxa 4377 (4), pp. 565-574 : 569-570

Triancyra cucphuongensis sp. nov.

( Figure 3 )

Diagnosis. Ground colour yellow with black marks; occipital carina interrupted dorsally; scutellum with V-shaped striation on anterior half; tergite 4 onwards with longitudinal blackish/black stripes connecting to transverse anterior and posterior bands.

Material examined. Holotype: ♀ ( RMNH), Ninh Binh, Cuc Phuong NP, 225 m a.s.l., 29.xii.2000 – 31.i.2001, P.Q. Mai leg.

Description of female holotype. Head: antenna with 27 flagellomeres, first flagellomere 1.3× length of second; frons smooth with fine punctures laterally; face as high as wide, with fine, sparse punctures laterally, medially densely and coarsely punctate; clypeus about 0.4× as high as wide, apical margin slightly concave; malar space 0.5× longer than basal width of mandible, granulose; mandible with lower tooth slightly longer and broader than upper; inner margins of eyes weakly convergent medially; diameter of lateral ocellus 0.8× as long as ocellar-ocular distance, distance between posterior ocelli 1.1× as long as ocellar-ocular distance; vertex with large punctures; occipital carina evenly curved, interrupted dorsally, ventrally meeting hypostomal carina about 0.4× basal mandible width from base of mandible.

Mesosoma. Epomia present, short; pronotum polished, with dense, small punctures along dorsal and posterior margins; mesoscutum 0.9× as long as wide at anterior level of tegulae, notauli present, short; scutellum punctate with V-shaped striation on anterior half, lateral carina present anteriorly; metascutellum polished, impunctate; mesopleuron with dense, small punctures anteriorly and ventrally, medially with sparse punctures, epicnemial carina extending nearly to groove below subalar prominence; metapleuron with dense punctures; propodeum with dense punctures laterally, polished and sparsely punctate dorsally, with shallow groove anteriorly, posterior transverse carina present, area petiolaris polished, distance from pleural carina to propodeal spiracle about 0.8× length of spiracle; fore basitarsus 1.6× second tarsomere; mid basitarsus 1.5× second tarsomere; hind leg with femur 5.3× as long as wide, 0.8× length of tibia, tarsus slightly longer than tibia, basitarsus 1.6×second tarsomere, fifth tarsomere 1.1× longer than third, 0.7× second. Fore wing length 10.2 mm, vein Rs&M distad of cu-a about 0.4× length of cu-a, vein 2 rs-m basad of 2 m-cu by about 0.4× length of 2 rs-m, hind wing with first abscissa of vein Cu 1 very short.

Metasoma. Tergites densely, coarsely punctate, especially on anterior part of tergite 2 onwards; first tergite 1.15× as long as apical width, with smooth and polished posterior band; second tergite 1.35× as long as first tergite, posteriorly with narrow smooth band; ovipositor sheath about 4.6× length of hind tibia, 1.5× length of fore wing, lower ovipositor valve with 9 apical teeth, upper valve with 5.

Colour. Ground colour yellow with black marks; antenna with apical flagellomere yellowish, outer face of first and second flagellomeres brown; frons medially to ocellar area and vertex black, broadening to compound eyes; occipital area largely yellow; mandibular teeth and malar space black; pronotum posterior margin black; mesoscutum black except large rectangular area medially and two lateral longitudinal stripes yellow; mesopleuron with anterior and posterior margins black, anterior patch expanding medially and ventrally; mesosternum black anteriorly; metapleuron and propodeum black anteriorly and posteriorly; tergites with black bands both anteriorly and posteriorly; tergite 4 onwards with median longitudinal blackish to black stripes; hind leg with black marks on coxa apically, femur basally reddish brown, tarsus black; wings with apical margin infuscated.

Male. Unknown.

Comparison. The new species can be distinguished from its congeners by the V-shaped striation on the anterior half of the scutellum. In general colour pattern, the new species is most similar to Triancyra latifacialis Wang & Hu, 1992 . However, the metasomal tergites of the new species are marked with black instead of ferruginous in T.

latifacialis . In addition, the new species has its occipital area largely black and its face as long as wide whereas in T. latifacialis the occipital area is entirely yellow and its face about 0.7× as high as wide

Etymology. The new species is named after its type locality, Cuc Phuong National Park.

Distribution. Currently known only from the type locality.

Ecological notes. The single specimen was collected in limestone forest at an elevation of 225 m a.s.l.

Figures

FIGURE 3. Triancyra cucphuongensis sp. nov. (Holotype female): a. face; b. lateral view of mesosoma; c. tergites; d. dorsal view of scutellum and propodeum.