Vespina sichuana Hirowatari, Huang & Wang, sp. nov.

(Figs 1E, F, 2E, F, 3E, F, 7–12, 13A, B)

Type material: Holotype ♂, “[China] Longcangou / Ya’an Sichuan / 17.vii.2017 / 25.vii.2017 em.”, “ G.H. Huang / M. Wang ” in HUNAU.

Paratypes: 7 ♂, 11 ♀, same locality as holotype, larvae 18–24.vi.2016, emerged 15–29.vii.2016, G.H. Huang, host plant: Castanopsis fargesii, sample ID: SaY93 (HUNAU); 18 ♂, 11 ♀, larvae or pupae 17.vii.2017, emerged 18–26.vii.2017, G.H. Huang, M.Wang, host plant: Castanopsis fargesii, sample ID: SaY94 (♀), genitalia slide no. SY480, (HUNAU).

Other material. Larvae: 5 exs 18–24.vi.2016, Longcangou, Ya’an, Sichuan, China, G.H. Huang; pupae: 12 exs 17.vii.2017, Longcangou, Ya’an, Sichuan, China, G.H. Huang and M.Wang, sample ID SaY92 (a part of larvae and pupae were preserved in 80% ethanol; all collected on Castanopsis fargesii, Fagaceae).

Diagnosis. Distinguished from other Vespina species by the scattered blackish brown scales on the forewing and the indistinct dark-brown stria along the discal cell. In the male genitalia, the pecten of the valva is very long, nearly half the length of the valva, consisting of more than 30 spines. In the female genitalia, the anterior end of the apophysis posterioris is extremely swollen, 3–6 × as wide as the base.

Description.

Male (Figs 1E, 2E, 3E, 7A). Wingspan 9.0 mm in holotype, 8.0–9.0 mm in paratypes (n = 25).

Forewing length 4.2 mm in holotype, 4.0– 4.7 mm in paratypes (n = 25).

Male. Head: Vertex and frons with yellow hairs, mixed with light-brown hairs on the posterior, entirely rough (Fig. 2E); antenna 3/4 the length of the forewing. Ocellus absent. Compound eye large. Maxillary palpus short (slightly shorter than labial palpus), pale yellow mixed with dark brown. Labial palpus porrect, short and slender, pale yellow mixed with brown, second segment with several distal blackish-brown bristles.

Thorax: Tegula, prothorax and mesothorax dorsally dark brown with a weak purple gloss. Metathorax with dark brown scales on the posterior. Foreleg dark brown, partly mixed with pale yellow; midleg dark brown, partly mixed with pale yellow, with dark brown tibial spurs; hindleg ochreous brown dorsally, partly mixed with pale yellow, with dorsal and ventral pale yellow hairs on the tibia, and pale yellow tibial spurs. Wings narrow. Forewings dark brown with scattered blackish brown scales, those on the basal 1/3 rising; an indistinct short blackish-brown stria present at the end of the discal cell with 12 veins, all veins arising separately from the discal cell; accessory and intercalary cells, indistinct. Hindwing, dark brown. Frenulum consisting of a single large bristle followed by 12–15 pseudofrenular bristles.

Abdomen: Dorsal part dark brown with golden luster, terminally with brown tufts of long hairs. Ventral part similar to dorsal part, terminally with brown smooth scales.

Female (Figs 1F, 2F, 3F, 7B, 11G, H). Wingspan 8.0–11.0 mm (n = 22). Forewing length 4.4–5.0 mm (n = 22). Coloration of the head and wings similar to that of the male, but wings tend to be brighter than in males. Frenulum absent or reduced with 17–22 thin pseudofrenular bristles.

Male genitalia (Fig. 8): Uncus hooked. Vinculum and saccus triangular and slightly shorter than the valva in length. Valva spatulate over the apical 1/2, width 1/2 of the base. Sacculus not expanded; pecten long, nearly half the length of the valva, consisting of 30–36 spines arranged in a single row midway along the ventral margin. Transtilla present and horn-shaped. Phallus relatively short, slightly shorter than valva, anteriorly swollen, with a large spinelike subapical carina penis; cornuti consisting of many minute spines. Juxta, broad.

Female genitalia (Fig. 9): Apophyses stout, each anterior end swollen and trumpet-shaped; apophysis posterioris slightly shorter than apophysis anterioris, with the anterior end extremely swollen, 6 ×as wide as the base, and the posterior half depressed and expanded laterally. Apex of ovipositor dorsoventrally flattened with one median semicircular projection. Spermathecal vesicle small and roundish. Corpus bursae elongate ellipsoidal; signa, absent. Ductus bursae relatively short, 1/2 as long as corpus bursae, weakly sclerotized near the caudal portion of the corpus bursae.

Immature stages.

Pre-mature larva: Not examined.

Mature larva (Figs 10E, F, 11 A–C). Color yellowish-white.

Length approximately 4.0– 4.8 mm (n = 5). Body: Stout and fat. Head: Head capsule pale-yellow with palebrown area around clypeus; enclosed area of six stemmata blackish-brown. Head capsule flattened. Posterior margin more bluntly V-shaped than that of the pre-mature larva. Antenna with three weakly sclerotized segments. Thorax: Thoracic tergites not well-sclerotized. Prothoracic spiracle not pigmented. Pretarsus with a squamiform seta adjacent to the claw. Abdomen: Yellowish-white with no distinctive pigmentation. Prolegs reduced; crochets reduced or present as an indistinct transverse band consisting of a row of 4–8 spines on segments 3, 4, 5, 6, and a row of 12–16 transverse spines on segment 10. Spiracles small oval on segments 1–8.

Pupa (Figs 11 D–F, 12). Length 3.3–4.0 mm; width 1.2–1.4 mm; height 0.8–0.9 mm (n = 8). Color: Pale-yellow. Body flattened dorsoventrally. Vertex smooth. Galea short, shorter than the labial palpus. Antenna extending beyond wing tip. Wings extending to abdominal segment 8. Anterior half of abdominal segments, weakly pigmented and dorsally pale-brown. Abdominal segments 3–8 with minute scattered tergal spines; spines on abdominal segment 3 indistinct. A pair of dorsal hooked spines on the caudal margin of segment 8. Spiracles weakly protruded on abdominal segments 2–8, especially on 7 and 8.

Etymology. The specific name is derived from the type locality, Sichuan Province.

Barcode data. DNA barcodes of the three specimens were generated (Table 1) and their sequences showed no difference (Table 3). The closest sequences were V. meridiana sp. nov. (SaY448) and V. nielseni (SaY97) (pairwise distance: 7.7%).

Host plant. Fagaceae: Castanopsis fargesii.

Biology. All examined adults were reared from larvae or pupae within portable cases collected from host plants. In 2016, we collected portable cases of mature larvae during middle- to late-June. In 2017, we collected the pupae in portable cases during mid-July; all adults emerged in middle- to late-July during both years. This shows that the adults of this species fly in middle- to late-July in the type locality. However, we were unable to collect any flying adults during the daytime nor those attracted by light at night.

Distribution. China (Sichuan Province).

Remarks. Although the host plant Castanopsis fargesii is widely distributed in southern China and Taiwan (Hong & Blackmore 2015), we have never found the larval portable case or larval feeding trace of Vespina sichuana anywhere other than in the Sichuan Province. However, the larval portable cases that seem to be of the genus Vespina are found in Taiwan on some evergreen oaks (S. Yagi, unpublished data).