Xestia lanceolata, Gyulai, 2018

Gyulai, Péter, 2018, A new species of Xestia H, 1818 (Lepidoptera, Noctuidae) from China, Zootaxa 4514 (3), pp. 445-448 : 445-448

Xestia lanceolata sp. n. ( Figs 1, 2, 3 , 7, 8 )

Holotype. Male ( Figs 1 , 7 ), China, Yünnan, 40 km North-East of Shangrila town, 4700 m a.s.l., 15–16.VI.2017, native collector leg.; slide no. GYP 4934m (coll. PGM, Miskolc, Hungary, later to be deposited in the HNHM).

Paratypes. Two males with the same data, slide No. GYP 4904m; one male, China , Yünnan, Deqen pass, 4600 m a.s.l., 10–12.VI.2017, native collector leg., (coll. PGM, Miskolc, Hungary) .

Diagnosis. Xestia lanceolata sp. n. ( Figs 1, 2, 3 ) is a medium sized species, similar to X. diagrapha ( Boursin, 1963) ( Figs 4-5 ), from which it is best distinguished by the size, some of the external features and the study of the male genitalia. The distinguishing external features are as follows: the new species is significantly larger than X. diagrapha (28–30 mm, versus 24–26 mm); the male antennae bipectinate versus finely ciliate in the X. diagrapha ; the forewing apex is more elongate; the ground colour of the forewings, including the basal area, is darker and greyish,, versus brownish in X. diagrapha with the basal area conspicuously whitish. Hindwings of X. lanceolata are also darker, greyish and not light brown; the orbicular stigmata are elongate, larger than in X. diagrapha , and without the fine white encircling.

Another somewhat similar, but not related species is Brachylomia pygmaea ( Draudt, 1950), ( Fig. 6 ). X. lanceolata is somewhat larger (28–30 mm, versus 25–27 mm) and differs significantly in the more elongate forewing apex; in being much darker and greyish (not yellowish); in the more elongate orbicular and reniform stigmata; the much darker hindwings and darker undersides of all the wings, with the conspicuous presence of the discal spot in the hindwing, which is not visible in the whitish hindwing of B. pygmaea.

In the male genitalia, the differences between X. lanceolata sp. n. and X. diagrapha are found in the shape and size of the uncus, harpe, cucullus, aedeagus and in the configuration of the vesica. X. lanceolata ( Figs 7, 8 ) differs from X. diagrapha ( Fig. 9 ) by its strong, lanceolate, apically hooked uncus (it is spatulate and broadly flattened apically in X. diagrapha ); larger, longer and not falciform harpe, and larger cucullus. Additionally, the broadly tubular vesica, recurved dorsad with a robust, elongate, sclerotized bar, deriving from the medio-dorsal section of aedeagus, are diagnostic characters and provide easy recognition of the new species relative to X. diagrapha , in which the thin, elongate sclerotised bar is positioned ventrad and the vesica also recurved ventrad.

The male genitalia (the presence of the pollex and harpe, the shape of the valvae, the lack of the corona in the cucullus) of X. lanceolata clearly indicate that it belongs to the subfamily Noctuinae , while B. pygmaea ( Fig. 10 ) is similar only superficially; the male genitalia (the absence of the pollex, the short sacculus, the presence of a short corona in the cucullus) in this latter species reflect its placement in the subfamily Xyleninae .

Description ( Figs. 1, 2, 3 ). Wingspan 28–30 mm, length of forewing 13–15 mm. Male. Antennae bipectinate, vesture of body and forewing ground colour variegate shaded grey, with a slight red-brown suffusion in specimens. The most remarkable external features of the new species are the pointed elongate forewing apex, the black basal dash, a more or less well discernible broad black definition of the prominent intercellular streak of the medial line, a more or less shallow claviform stigma, elongate grey orbicular and reniform stigmata, a wavy antemedial line, an arched—crenulate postmedial line, a slightly sinuous, fine, ochreous subterminal line, and a rather unicolorous, pale brown to greyish hindwing with a fine brown discal spot and pinkshaded grey setae.

The male genitalia ( Figs 7, 8 ) can be characterized by the strong, lanceolate, apically hooked uncus; an almost straight, basally broad, terminally slender harpe; a dorsally rounded cucullus section of the valva; and a fine pollex. The aedeagus is somewhat curved, the vesica broadly tubular and recurved dorsad with a conspicuous, robust, elongate, sclerotized bar, somewhat serrated dorsad, derived from the medio-dorsal section of the aedeagus.

Female is not known.

Distribution. The four specimens have been found only in the high mountain region of Yünnan, China, in 4600- 4700 m, in the beginning of summer period.

Etymology. The specific name indicates the robust, lanceolate uncus.

Figures

FIGURES 1–6. Adults. 1. Xestia lanceolata sp. n., holotype, male, China, Yünnan (PGM); 2. Xestia lanceolata sp. n., paratype, male, China, Yünnan (PGM); 3. Xestia lanceolata sp. n., paratype, male, China, Yünnan (PGM); 4. Xestia diagrapha (Boursin, 1963), male, China, Sichuan (PGM); 5. Xestia diagrapha (Boursin, 1963), male, China, Sichuan (PGM); 6. Brachylomia pygmaea (Draudt, 1950), male, China, Sichuan (PGM).

FIGURES 7–10. Male genitalia. 7. Xestia lanceolata sp. n., holotype, China, Yünnan, slide no. GYP4934 (PGM); 8. Xestia lanceolata sp. n., paratype, China, Yünnan, slide no. GYP4904 (PGM); 9. Xestia diagrapha (Boursin, 1963), China, Sichuan, slide no. GYP2376 (PGM); 10. Brachylomia pygmaea (Draudt, 1950), China, Sichuan, slide no. GYP4905 (PGM).