Xestioplexia albicollis, Gyulai, Peter, Ronkay, László & Saldaitis, Aidas, 2015

Gyulai, Peter, Ronkay, László & Saldaitis, Aidas, 2015, Xestioplexia gen. n. with the description of a new species from China (Lepidoptera: Noctuidae), Zootaxa 4007 (1), pp. 131-137 : 132-136

Xestioplexia albicollis sp. n.

( Figs 1–3 , 7, 8, 10 )

Holotype: Male ( Fig. 1 ), China, North Sichuan, road Jiuzhaigou-Songpan, 2900 m, N33°08.770’, E103°43.624’, 27.VIII.2014, leg. Floriani & Saldaitis; slide No. PGY 3924m (coll. PGM, later to be deposited in the HNHM).

Paratypes. China. 7 males, 4 females ( Figs 2, 3 ), with the same data as the holotype; slide Nos PGY 3993m, PGY3922f, 1 female, China, North Sichuan, near Jiuzhaigou, 2161 m, N33°18.955’, E103°55.531’, 25–26.VIII.2014, leg. Floriani & Saldaitis (colls AFM & ASV).

Diagnosis. The detailed comparison of the members of Xestioplexia with the externally more or less similar genera is given in the diagnosis of the new genus. The two congeners are easily distinguishable both by their external and genital features. Xestioplexia albicollis ( Figs 1–3 ) differs externally from X. colorata ( Figs 4 –6) by its more unicolorous blackish forewings and thoracic pubescence, white collar and clear white hindwing, larger and more quadrangular orbicular and reniform stigmata, and the much less prominent, generally faint and simple, not whitish filled crosslines of the forewing. The male genitalia of X. albicollis ( Figs 7, 8 ) and X. colorata ( Fig. 9 ) are surprisingly similar, despite the rather large external differences, indicating their sister taxon relationship. Xestioplexia albicollis differs from X. colorata by its much longer and evenly thinner uncus, somewhat more elongated valvae with slenderer and longer sacculus, somewhat different harpe-ampulla complex (the harpe is thinner, more oblique, and projecting more distally, the vinculum is larger, broader, the aedeagus is longer and more curved, with longer dorsal plate and differently serrate ventro-lateral plate. The ventral plate of X. albicollis has three more or less detached, knob-like, more evenly serrated appendages; this plate in X. colorata has long, sclerotized area with unevenly serrated surface having four stronger teeth.

Description. Wingspan 34–40 mm. The most remarkable external features of the new species is the bipectinate antennae of the males, while filiform of the females, the black forewing combined with clear white hindwing, the faint transverse lines of the forewing and the whitish (males) or white (females) vertex and collar. The main typical features of the male genitalia are the evenly thin and long uncus, the characteristic structure of the harpe-ampulla complex with ventro-lateral, strikingly long and tapered process, the distally evenly slender valva, the entire lack of pollex, the rather short, curved aedeagus with conspicuously strongly sclerotised three, more or less detached, knob-like, somewhat serrated carinal appendages and the large, ample vesica bearing a medial diverticulum terminated in a short, pointed cornutus ( Figs 7, 8 ); those of the female genitalia ( Fig. 10 ) are the strongly sclerotised large, calyculate antrum and the more or less similar shaped and sized, also strongly sclerotised posterior section of ductus bursae.

Biology and distribution. The eight males and four females were collected at ultraviolet light on 25–27 August 2014 in southwest China's Sichuan province in a remote, area located at the southern end of the Minshan mountain range. The collecting area is near the incomparable Jiuzhaigou National Park. The climate in the valley is cool, with a mean annual temperature 7.2 °C and total annual rainfall is 661 mm, 80% of which occurs between May and October. Jiuzhaigou's ecosystem is classified as temperate broad-leaved forest and woodlands, with mixed mountain and highland systems. The 300 km ² heart of this scenic area is covered by virgin mixed forests including oaks and endemic varieties of rhododendron and bamboo.

Etymology. The new species is named after its white collar.

Figures

FIGURES 1 – 5. Xestioplexia spp. adults. 1. X. albicollis sp. n., male, holotype, China, Sichuan (PGM); 2. X. albicollis sp. n., male, paratype, China, Sichuan (AFM); 3. X. albicollis sp. n., female, paratype, China, Sichuan (AFM); 4. X. colorata, male, paratype, China, Tibet (NMB); 5. X. colorata, male, China, Tibet (NMB); 6. X. colorata, female, China, Tibet (NMB).

FIGURES 7 – 10. Xestioplexia spp. Male and female genitalia. 7. X. albicollis sp. n., male, holotype, prep. PGY 3924; 8. X. albicollis sp. n., male, paratype, prep. PGY 3993; 9. X. colorata, male, paratype, China, Tibet, prep. Ch. Boursin, Bsl. 20; 10. X. albicollis sp. n., female, paratype, prep. PGY 3922.