Megastigmus daduheensis, Chen & Kuang & Tao & Xiong & Mao, 2023

Chen, Xiaoxiao, Kuang, Jingge, Tao, Wenjing, Xiong, Zhongping & Mao, Kangshan, 2023, A new species of Megastigmus (Hymenoptera, Megastigmidae) from China, Biodiversity Data Journal 11, pp. 102828-102828 : 102828

Megastigmus daduheensis sp. n.

Materials

Type status: Holotype. Occurrence: occurrenceDetails: CollectionCode : NHMSU-20201015-XJ; GenBank No : COI ( ON421529 ) and Cytb ( ON478368 ).; individualCount: 1; sex: female; lifeStage: adults; occurrenceID: C3C6985C-AF91-54BA-ACE7-7689077A8ED3; Taxon : scientificName: Megastigmus daduheensis; order: Hymenoptera ; family: Megastigmidae ; genus: Megastigmus ; specificEpithet: daduheensis; Location : country: China; stateProvince: Sichuan; locality: Aba Autonomous Prefecture of Tibetan and Qiang ( Ngawa ), Xiaojin County, Ri'er Township (102°35′ E, 30°59′ N) ; locationRemarks: label transliteration:"15 Χ 2020, coll. Wenjing Tao, Wentao Wang and Xue Li" Type status: Paratype. Occurrence: individualCount: 38; sex: female 36 male 2; lifeStage: adults; occurrenceID: E65DFF05-F6EE-579F-9958-FBF8F77337EE; Taxon : scientificName: Megastigmus daduheensis; order: Hymenoptera ; family: Megastigmidae ; genus: Megastigmus ; specificEpithet: daduheensis; Location : country: China; stateProvince: Sichuan; locality: Aba Autonomous Prefecture of Tibetan and Qiang ( Ngawa ), Xiaojin County, Ri'er Township (102°35′ E, 30°59′ N) ; locationRemarks: label transliteration:"15 Χ 2020, coll. Wenjing Tao, Wentao Wang and Xue Li"

Description

Female. Length (body + ovipositor): 2.81 ~ 3.05 + 3.09 ~ 3.17 mm. Colour: body (Fig. 1 A, H) alternate distribution of yellow, brown and black; head: vertex brown, face yellow, clypeus with apical half dark brown; head antennae light brown; eye reddish-brown; clypeus with apical half dark brown; pronotum brownish-yellow; mesoscutum black anteriorly to brownish-yellow posteriorly; scutellum dark yellow; metanotum light yellow; propodeum black (Fig. 1 J); leg brownish-yellow; wing hyaline, vein and the enlarged part of stigmal vein dark brown, stigma light brown; setae of body pale, having black base; hind coxa black, femora and tibia brown; gaster dark brown; ovipositor dark brown.

Head. Head about 1.6 × as wide as long in dorsal view; whole face with pale, dense setae; frons with many obvious striated sculptures; ocellus arranged in a blunt triangle, POL about twice as long as OOL and OCL; several short setae between ocelli, the rest on other parts of head (Fig. 1 B-E). Antennae moniliform, arising from the area below centre of face; scape almost 3.5x as long as width, pedicel about 0.4 of scape length, anellus about 0.25 of pedicel length; relative length/breadth (ratio) of funiculars (F1-F7) as follows: F1 57/29 (1.96), F2 84/38 (2.21), F3 97/39 (2.48), F4 83/46 (1.80), F5 74/47 (1.57), F6 79/45 (1.76), F7 62/45 (1.38); clava (C1-C3) with relative length/breadth (ratio)131/47 (2.79) (Fig. 1 F).

Mesosoma. Pronotum and mesoscutum with irregular sculpture and orientation of rugae, notauli brown and sparse setae scattered on both sides (Fig. 1 H); axillae with oblique longitudinal ridge; scultellum with transverse costula and white setae on both sides; propodeum with oriaceous, callus with long white setae and irregular reticulate sculpture; callus densely covered with white long setae. Basal cell of fore wing with more than ten setae and the lower part of the basal cell closed by a row of setae; marginal vein shorter than postmarginal vein; stigma large and 2.2 × as long as width, stigma vein short and 0.11 × as long as stigma (Fig. 1 G). Hind coxa with white long setae on both sides, femora and tibia densely covered with white setae (Fig. 1 A).

Metasoma. Gaster not compressed laterally, 1.21 mm long, with sparse bristles scattered with four black horizontal bands and the spacing between the horizontal bands decreasing successively (Fig. 1 A). Ovipositor densely covered with brown long setae and 4.5 × as long as hind-leg tibia.

Male. Body black, 2.4 ~ 2.6 mm long (Fig. 1 I). Gaster black, 1.0 mm long, 1.5 × as long as hind tibia. Antennae brown. Femora wider than female femora. Marginal vein tan, stigma dark brown. Antennae flagellum about the same length as gaster, funicle length greater than width, anellus about 1/3 of pedicel length. Stigma 1.6 × as long as width, stigmal vein short and 0.18 × as long as stigma. Other morphology is similar to female.

Diagnosis

The key from China distinguished the females of Megastigmus daduheensis sp. n. by their body length less than 5 mm, ovipositor exceeding body length, stigma neck less than 0.5 times the width of the stigma and scultellum dark yellow. (Fig. 1 A, G, E). Megastigmus daduheensis sp. n. is similar to Megastigmus duclouxianae Xu & He, 1995 (Fig. 2 A, B) and Megastigmus sabinae Xu & He, 1989 (Fig. 3 A,B), but can be distinguished from the latter two species by: 1) stigma light brown, 2.2 × as long as width, stigma neck short and 0.11 × as long as stigma; 2) ovipositor 4.5 × as long as metatibia; and 3) mesosctum black anteriorly to brownish-yellow posteriorly.

Etymology

The new species is named after its type locality, Daduhe, Sichuan Province.

Biology

The eggs are laid in the cones of Cupressus chengiana S.Y. Hu, feeding on the nuts and the adults fly out of the cones from October to November every year.

Figures

Figure 1. Megastigmus daduheensis sp. n. A-H female holotype; A Body, lateral view; B Head, lateral view; C Head, ventral view; D Head, dorsal view; E Head, frontal view; F Antenna; G Fore wing; H Head and mesosoma, dorsal view; I Male, Body, lateral view.

Figure 2. Megastigmus duclouxianae, female; A Body, lateral view; B Head and mesosoma, dorsal view.

Figure 3. Megastigmus sabinae, female; A Body, lateral view; B Head and mesosoma, dorsal view.