Prodasineura lancastrei sp. nov.

urn:lsid:zoobank.org:act: 6A004DD2-86D3-455A-A266-B7139FA6AFF0

Figs 9B, E–F, 10 C–D, 11 B, D, F, 12 C–D, 13 E–F, 14 C–D, 15 B, 16 B, 18

Diagnosis

Differing from most other congeners and all Vietnamese species of Prodasineura by darkened apical wings (Fig. 14C) in male and morphology of posterior pronotal lobe with three flattened horns in female (Fig. 13 E–F). In Vietnam, P. lancastrei is superficially most similar to P. kong by sharing the same thin antehumeral stripe on the male synthorax (Fig. 9 A–B), but differing by the following characters: in male, transverse band on dorsal head of P. lancastrei narrow (Fig. 9B), wider in P. kong (Fig. 9A); appendages of P. lancastrei mostly black (Fig. 9 E–F), paraprocts yellowish apically in P. kong (Fig. 9 C–D); cerci of P. lancastrei (Fig. 9E) in lateral view not pointed, ventral expansion convex along posterior margin as opposed to concave in P. kong (Fig. 9C). Female of P. lancastrei differing by three horns (Fig. 13 E–F) in stead of two short, robust horns in P. kong (Fig. 13 C–D).

Etymology

This species is named after Mr. Luis de Lancastre (born on 20 December 1990) in appreciation of his financial aid for our fieldwork. A noun in the genitive case.

Material examined

Holotype

VIETNAM • ♂; Nghe An Province, Con Cuong District, Mon Son Commune, a small stream near Khe O Forestry Latch, Pha Lai Ranger Station; 19.52167° N, 105.545° E; 66 m a.s.l.; 12 May 2019; Q.T. Phan leg.; ZCDTU 2019051212-ODO

Paratypes

VIETNAM • 4 ♂♂, 1 ♀; all mature; same collection data as for holotype; ZCDTU 2019051213-17- ODO.

Description

Male (Figs 9B, E–F, 10C–D, 12C, 14C, 15B)

MEASUREMENTS. Hindwing 19 mm, abdomen (including appendages) 31.5 mm.

HEAD. Labrum dark red with black dot medially. Mandibles yellow, pattern extending to level of postclypeus. Anteclypeus dark red, postclypeus matt black (Fig. 9B). Antennae entirely black. Front matt black except for complete narrow transversal reddish stripe running from eye margins, encompassing anterior ocellus. Rear of head entirely black (Fig. 12C).

THORAX. Prothorax black, orange markings as in Fig. 9B; distal margin of anterior, posterior pronotal lobe with small spot, middle of pronotal lobe with large oval spot. Propleuron entirely black. Synthorax black, on each side with narrow orange antehumeral stripe, two other distinct stripes: reddish one on metepisternum and yellowish ones on lower margin of metepimeron (Fig. 12C).

LEGS. Coxae black, lateral yellow lines; trochanter yellow, flexor margin black; femur entirely black; tibia black, flexor surface yellow; tarsus, claws entirely black.

WINGS. Hyaline, darkened from about level of pterostigma (Figs 10C, 14C, 15B). Forewings slightly longer than hindwings, Px 17, 14 in forewings, hindwings respectively. No anal bridge (Fig. 10C). Pterostigma black, covering slightly more than one underlying cell.

ABDOMEN. Mostly black except for yellow triangular spots at lower margins of S1; ventro-lateral sides of S2 with yellowish bands; S3–6 with dorsally interrupted half-rings along anterior margin; anterior S3 with orange spot; S7–10 entirely black (Fig. 14C).

ANAL APPENDAGES. Mostly black except for dark yellowish tips of cerci; cerci axe-shaped, broadened ventro-apically, paraprocts entirely black, broad at base, narrower toward blunt tip (Fig. 9 E–F).

GENITAL LIGULA. Typically shaped for Prodasineura species, two robust flagella lateroapically, extending posteriorly, pointed at tip, bearing subbasal shorter flagellum, which expands apically as rounded lobe (Fig. 10D).

Female (Figs 11B, D, F, 12D, 13 E–F, 14D)

MEASUREMENTS. Hindwing 18.5 mm, abdomen (including appendages) 30 mm.

HEAD. Labrum, mandibles, genea, anteclypeus yellowish except for black spot beneath lateral side of mandibles, border of genae black, two separated black spots on anteclypeus; this pattern over postclypeus at level of base of antennae (Fig. 11B). Postclypeus, antennae entirely black. Front, rear of head black, obscure tiny transverse yellowish stripe at level of anterior ocellus (Fig. 12D).

THORAX. Prothorax black, yellowish laterally (Fig. 11B). Posterior pronotal lobe with three flattened horns (Fig. 13F), strongly erect in lateral view (Fig. 13E). Antehumeral stripe yellow, not reddish as in male, shorter, interrupted at about ¾ of mesepisternum (Fig. 11B).

LEGS. Same as male.

WINGS. Hyaline, forewings slightly longer than hindwings, Px 13, 12 in forewings, hindwings respectively. Pterostigma black (Fig. 14D).

ABDOMEN. Black, following pattern: S1 with two oval yellowish spots; S2 with narrow yellowish stripe along lower margin; S3–6 with dark reddish stripe along lower margin, oval yellowish spot on anterior segments, larger spot at about ¾ of each segment length (Fig. 14D); S7–9 black with yellowish stripe on lower margin; S10 black with oval yellow spot dorsally (Fig. 11D, F).

APPENDAGES. Entirely black; ovipositor black with distal end yellowish (Fig. 11D, F).

Variation in male paratypes

Two paratype males having yellowish compound eyes due to acetone treatment for preservation, other features of paratype specimens showing no significant differential features from holotype male. Compound eyes bright red in living males (Fig. 15B).

Distribution

Vietnam (Fig. 18): Nghe An (Con Cuong District, Mon Son Commune) Province.

Habitat and ecology

The new species was found in a densely vegetated, very narrow (about 1 m width) branch (Fig. 16C) of a shaded, shallow, narrow (about 1–3 m width) and rocky forest mountain stream with slow running water and a sandy bottom. Two other species of Prodasineura ( P. autumnalis and P. croconota) occurred in the same stream with P. lancastrei sp. nov.