Pnigalio eriocraniae Li & Yang

Li, Tao, Yang, Zhong-Qi, Sun, Shu-Ping & Wang, Rong, 2017, A new species of Pnigalio (Hymenoptera, Eulophidae) parasitizing Eriocraniasemipurpurellaalpina (Lepidoptera, Eriocraniidae) in China, with its biology and a key to Chinese known species, ZooKeys 687, pp. 149-159 : 149-152

Pnigalio eriocraniae Li & Yang sp. n. Figures 1, 2, 3-10, 11, 12-17

Etymology.

The specific name is derived from the host’s generic name Eriocrania .

Type material.

Holotype, ♀, (GSFPM), Ganchonggou, Huzhu County, Qinghai Province, leg. Tao Li, 31 May 2011, collected using intercept traps. Paratypes (101♀♀ 60♂♂): (GSFPM, 36♀♀ 12♂♂ are deposited in CAF): 32♀♀ 2♂♂, same data as holotype; 1♀ 4♂♂, same but 10 May 2011; 13♀♀ 15♂♂, same, 30 May 2011; 9♀♀ 5♂♂, same, 1 June 2011; 5♀♀ 9♂♂, same, 2 June 2011; 5♀♀ 3♂♂ (reared from larva of Eriocrania semipurpurella alpina Xu), same, 27 June 2011; 11♀♀ 6♂♂ (reared), same, 28 June 2011; 7♀♀ 4♂♂(reared), same, 29 June 2011; 18♀♀ 12♂♂ (reared), same, 30 June 2011.

Diagnosis.

Body (Fig. 1) green to blue-green with purple metallic tinge. Antenna (Fig. 5) dark brown. Scape same color as body. Posterior margin of mesoscutum with one pair of bristles (Fig. 6, arrows). Propodeal disc smooth; costulae absent (Fig. 6) or if present, then weak and not reaching median carina (Fig. 9, arrow). Fore wing (Fig. 11) length 2.7 × width; costal cell length 10.0 × width. Hind coxa (Fig. 7) coarse reticulate dorsally; hind femur, tibia (apical portion brown), yellow to yellowish white.

Description.

Female, holotype (Fig. 1). Length of body of females 3.1-3.4 mm. and of fore wing 2.8-3.0 mm. Body green to blue-green with purple metallic tinge. Vertex golden-green. Antenna (Fig. 5) dark brown. Mandible brown. Maxillary and labial palpi, tegula, fore leg (coxa same color as body, tarsi and claw pale brown), mid leg (coxa same color as body, tarsus 4 brown), hind leg (coxa same color as body, apical portion of tibia and tarsi 3-4 brown) yellow to yellowish white. Wing membrane hyaline, venation and pilosity brown.

Head. In dorsal view, width 2.8 × length. Ocellar triangle convex, micro-reticulate, smooth with long brown setae. Ocelli medium-sized, and lateral areas of ocellar triangle concave. POL 1.7 × OOL, OOL 1.6 × OD. Area between eyes and ocellar triangle smooth. Head (Fig. 3) in anterior view width 1.4 × height. Eye oval, with dense microtrichia; length 1.3 × width. Malar space 0.5 × length of eye, malar sulcus straight and obvious. Face (Fig. 3) smooth, micro-reticulate texture, with sparse long white setae; Median portion of lower face with fine transverse wrinkles. Lower margin of toruli located above ventral line of eyes (Fig. 3). Distance between toruli 0.9 × diameter of toruli, 0.7 × distance between socket and eye. Antenna (Fig. 5) with 4 funiculars and 2 clavomeres. Scape length 3.8 × its width, reaching median ocellus, 3.3 × as long as pedicel. Pedicel length 1.4 × its width. Funicle 1 length 2.8 × as long as pedicel. Ratio of length of funicles 1.6:1.4:1.3:1.0, and ratio of width 1.0:1.1:1.1:1.1. Clavomere 1 length 1.3 × as long as segment 2. Mesosoma (Figs 6-7). Width about 1.2 × as long as head. Mesosoma reticulate, length 1.4 × width. Pronotum length 0.3 × as long as mesoscutum, width 0.7 × mesoscutum. Mesoscutum (Fig. 6) slightly convex, length 0.7 × its width, with dense white setae; anterior half of notaulus obvious; median and apical portions of mesoscutum reticulate, setae relatively sparse; posterior margin with one pair of stout bristles (Fig. 6, arrows). Axilla elongate, micro-reticulate. Mesoscutellum (Fig. 6) nearly circular, sublaterally more coarsely reticulate than apical and median portions; laterally micro-reticulate; with two pairs of bristles. Dorsellum narrow, median length 0.6 × as long as propodeum length. Propodeal disc (Figs 6, 9) smooth; width of median area 1.6 × its length; costula incomplete (Fig. 9, arrow); spiracles nearly circular, posterior to hind margin of metanotum; callus densely setose. Fore wing (Fig. 11) length 2.7 × width; costal cell length 10.0 × width; area of speculum mostly bare posterior to parastigma; marginal vein length 1.3 × length of submarginal vein, 1.8 × length of postmarginal vein; postmarginal vein length 2.1 × length of stigma. Lateral and ventral panel of pronotum and prepectus with coarse reticulate sculpture; mesepisternum (Fig. 7) imbricate anteriorly; subalar area and upper mesepimeron smooth. Dorsal area of hind coxa (Fig. 7) reticulate; basitarsus (Fig. 8) length 0.8 × as long as tarsus 2.

Metasoma (Fig. 10). Elongate-ovate in dorsal view; length about equal to head plus mesosoma, 2.0 × width of metasoma. Tergite 1 smooth; lateral area of tergite 2 with sparse white setae; sub-lateral portion of tergite 3 with sparse white setae; tergites 4-7 with dense setae; ratio of length of tergites 7.0:2.5:3.0:3.5:4.0:2.0. Ovipositor sheath slightly longer than apex of metasoma. Male (Figs 2, 17). Length of body 2.1-2.6 mm, and of fore wing 2.1-2.3 mm. Similar to female except as follows: Antennal (Fig. 4) flagellum dark brown; fore leg with coxa same color as body, basal half of femur brown with purple metallic tinge, apical tarsomere brown; mid leg with coxa same color as body, most of femur brown with purple metallic tinge, tarsus 4 brown); hind leg with coxa, most of femur same color as body, trochanters, apical half of tibia, tarsus 4 brown to fuscous, apex of femur and basal half of tibia yellowish brown; apex of tergite 1, tergite 2 and basal half of tergite 3 yellowish white to yellowish brown. Scape length 3.2 × width, 4.7 × length of pedicel; pedicle nearly circular; ratio of length of funiculars (Fig. 4) 1.0:1.6:1.6:3.1; funiculars 1-3 pectinate, projections with long setae. Dorsellum smooth, micro-reticulate. Costula absent.

Variation.

The variation of specimens is mainly focus on the body color, size, and costulae absent or present. The body color green with metallic tinge (26♀♀ 13♂♂) to blue-green with purple metallic tinge (76♀♀ 47♂♂); tarsi 1-3 of fore leg yellowish (72♀♀, others pale brown); apical portion of mid tibia brown (68♀♀); costula weak (79♀♀, Fig. 9) or absent (23♀♀ 60♂♂, Fig. 6). Costulae of male absent.

Biology.

Parasitoid eggs were deposited on the surface of the host’s cuticle (Fig. 12). It is a larval ectoparasitoid (Fig. 13) of the third to fourth instar larvae of E. s. alpina Xu ( Lepidoptera , Eriocraniidae ) which forms leaf mines on birch trees, Betula platyphylla Suk., B. albo-sinensis Burkill and B. utilis D. Don ( Betulaceae ) in Qinghai Province.

The prepupa (Fig. 14) is motionless, fusiform and with distinct lateral protuberances along the abdominal segments, length of body about 0.6-0.7 mm. The pupa is initially white to white brown (Fig. 15) and then begins to darken to brown or black (Fig. 16), with length 0.4-0.5 mm.

Distribution.

Northwestern China (Qinghai Province)

Remarks.

The new species is similar to Pnigalio maijishanensis Yang & Yao but can be distinguished from the latter by the following combination of characters: scape blue-green with purple metallic tinge; propodeal disc laterally smooth; hind coxa with coarse reticulate sculpture dorsally; hind femur, tibia (apical portion brown), yellow to yellowish white. In addition, the shape of the costulae and the stout bristle are different as indicated in the key.