Xestia rimas Gyulai, Ronkay & Saldaitis, 2013

Gyulai, P., Ronkay, L. & Saldaitis, A., 2013, Two new Xestia Hübner, 1818 species from China (Lepidoptera, Noctuidae), Zootaxa 3734 (1), pp. 96-100 : 99-100

Xestia rimas Gyulai, Ronkay & Saldaitis sp. n.

( Figs. 4 , 12–15 )

Type material. Holotype: Male, China, N-Sichuan, road Songpan - Jiuzhaigou, 3000 m, 3308.770’N, 10343.624’E, 23.vii.2011, leg. A. Floriani & A. Saldaitis, slide No PGY 3213m (coll. Peter Gyulai, later in Hungarian Natural History Museum , Budapest, Hungary) . Paratypes: 5 males, with the same data as the holotype, colls Peter Gyulai , Alessandro Floriani ( Milan , Italy) and Gintaras Rimas (Bendoreliai, Lithuania) Slide No PGY 2893m .

Diagnosis and Description. Wingspan 36–38 mm. The new species with its prominent morphological autapomorphies represents a unique lineage within the entire Holarctic genus Xestia s. l. Externally it slightly resembles Rhyacia mirabilis Boursin, 1954 and R. admiranda Gyulai & Ronkay, 2001 , but has a less robust body and broader trigonical forewings with a short apex and straight outer margin. The dark bluish-ashy grey forewing ground colour distinguishes it from the two bright greenish Rhyacia species ; the orbicular and reniform stigmata are lighter than the ground colour, but not so dark as those of R. mirabilis and R. admiranda . Xestia rimas ( Fig. 3 ) is also somewhat similar to certain other Holarctic larger, greyish coloured members of the subgenus Pachnobia Guenée, 1852 (formerly Anomogyna Staudinger, 1871 ; was synonymised with Pachnobia, Lafontaine, 1998 ) but is easily separable by the almost unicolorous dark bluish ashy grey forewing ground colour, the unusual light ochreous suffusion of the basal field, the large, regular, light ochreous-grey filled orbicular stigma and the conspicuous small, dark ochreous spot in the indistinct, darkened reniform stigma. Antennae filiform; legs blackish; hindlegs with a single long and two shorter spines; head, thoracic pubescence and palpi light ashy grey; palpi with black underside; abdomen light brown; antemedial line double, wavy; postmedial line simple, arcuate and serrated; both crosslines diffuse, blackish-grey; subterminal line obsolescent, with blackish trigonical costal patch and black arrowheads at inner side; hindwing brownish-grey, with darker cellular discal spot and wavy medial line; cilia of both wings ashy grey. The male genitalia ( Figs. 12–15 ) are typical of the subgenus Pachnobia but the distal part of the valva is more elongated, terminally bifurcate, and resembles those of some species of the subgenus Raddea Alpheraky, 1892 (formerly Erebophasma Boursin, 1963 ; was synonymised with Raddea, Lafontaine 1998 and Kononenko et al. 2012), especially Raddea hirsuta ( Chen, 1985) . The specific features of the male genitalia of X. rimas are the large, broadly calyciform juxta, with deep, laterally sinuous V-shaped dorso-medial incision; particularly distally elongated, terminally asymmetrically bifurcate, pointed valva; medium-large, thick and basally strongly curved, apically acutely pointed harpe; large knot-shaped carinal plate, appearing rather like a basal cornutus; the dorsally recurved, ample vesica with sclerotised, slightly serrated subbasal plate. Female unknown.

Bionomics and Distribution. The six males were collected at ultraviolet light on 23 July 2011 in Sichuan Province in a remote area located at the southern end of the Minshan mountain range ( Fig. 5 ). The collecting area is near Jiuzhaigou National Park. The climate in the valley is cool, with a mean annual temperature of 7.2 degrees C and total annual rainfall of 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. Among other summer noctuid species collected at the time were Haderonia albirena (Draudt, 1950) , Diphtherocome pallida (Moore, 1867) , Xestia morandinii Gyulai, Ronkay & Saldaitis, 2011 , Papestra florianii Gyulai, Ronkay & Saldaitis, 2011 .

Etymology. Dedicated to Mr. Gintaras Rimas (Bendorėliai, Lithuania) for his special interest in Xestia .

Figures

FIGURES 1–5. Xestia ssp. adults. 1. X. elisabetha sp. n., male, holotype, China, Sichuan (coll. P. Gyulai); 2. X. elisabetha sp. n., male, paratype, China, Sichuan (coll. P. Gyulai); 3. X. aplectoides, male, China, Yunnan (coll. P. Gyulai); 4. X. rimas sp. n., male, holotype, China, Sichuan (coll. P. Gyulai); 5. Mixed forest – the biotope of X. rimas sp. n., China, N-Sichuan, road Songpan/Jiuzhaigou.

FIGURES 12–15. Xestia ssp. males genitalia. 12. X. rimas sp. n., holotype, capsule, prep. PGy3213; 13. X. rimas sp. n., holotype, aedeagus, prep. PGy3213; 14. X. rimas sp. n., paratype, capsule, prep. PGy2893; 15. X. rimas sp. n., paratype, aedeagus, prep. PGy2893.