Argyresthia (Argyresthia) decurtata Liu, Wang & Li, 2017, sp. nov.
Creators: name: Liu, Tengteng
name: Wang, Shuxia
name: Li, Houhun
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Yponomeutidae
Argyresthia
Argyresthia decurtata

description: 31. Argyresthia (Argyresthia) decurtata, sp. nov.
(Figs. 39, 40, 108, 109, 164, 165, 220, 221, 269, 270)
Description. Adult (Figs. 39, 40) wingspan 12.5̄ 14.5 mm. Head yellowish white, face tinged with brown laterally. Labial palpus yellowish fuscous, fuscous on basal two segments ventrally and laterally. Antenna with scape pale yellowish white, pecten yellow; flagellum white, ringed with black. Foreleg with femur grayish fuscous on inner surface, a black line medially on ventral surface, tibia and tarsus blackish fuscous on inner surface, tibia dotted with black near base, at middle, and on distal part dorsally, tarsus black on distal part of each tarsomere dorsally, remainder yellowish white; midleg mostly yellowish white, femur blackish gray ventrally, tibia dotted with black near base and at middle dorsally, dotted with gray on distal part dorsally, tarsus black on distal part of each tarsomere; hindleg mostly gray, tarsus yellow mixed with gray on distal four tarsomeres basally. Thorax yellowish white; tegula brownish fuscous. Forewing ratio 4.1; grayish fuscous, suffused with fine black transverse striae; costa with several distinct black transverse striae on basal 4/5, with a small yellowish-white dot near apex; grayishfuscous streak below basal half of fold; dorsal band yellowish white, extending to before end of fold; dorsal streak from middle of wing blackish-gray, reaching near upper angle of cell, triangular and distinct between fold and dorsum, indistinct anteriorly; cilia yellowish white adjacent to yellowish-white costal dot, brownish fuscous around apex, grayish fuscous near tornus. Hindwing and cilia uniformly gray.
Male genitalia (Figs. 108, 109, 164, 165, 220, 221): Tuba analis shorter than width of valva. Socius covered with 21̄28 scale-like setae, bearing one or two setae posteriorly (Figs. 220, 221). Gnathos not inflated distally, without long thick setae apically. Valva widest at middle, dorsal margin arched before middle; a row of thick setae from disc near ventral margin to distal area. Saccus shorter than width of valva, with distal half conspicuously attenuate to narrowly rounded apex. Phallus curved at basal 3/5, 3.5 to 4.0 times as long as width of valva (Figs. 164, 165). Second sternite with about 13̄15 micro-setae in each row; eighth sternite V-shaped. Coremata present.
Female genitalia (Figs. 269, 270): Ovipositor 2.8 times as long as eighth segment. Anterior apophysis about 7/ 10 length of posterior, bifurcated before middle, branches fused, forming ventral margin of ostium bursae. Lamella postvaginalis narrowly band-shaped. Antrum tubular or slightly funnel-shaped, 1/3 length of eighth segment. Ductus bursae densely spinulate before and near opening of ductus seminalis; ductus seminalis originating from anterior 2/5 of ductus bursae. Corpus bursae oval, with dense micro-spines and denticles; signum with basal plate band-shaped, uniform in width, horns extending outward obliquely or horizontally, broad V-shaped, or nearly straight on anterior margin.
Variation (Fig. 40): Some specimens from Guizhou Province darker; thorax and tegula dark fuscous; forewing grayish fuscous; costa with a row of yellowish-white dots from basal 2/5 to 7/10, with two larger yellow spots at distal 3/10 and before apex; termen with several yellowish-white dots; dorsum with an indistinct V-shaped dark fuscous pattern at basal 1/4 open to costa, reaching near base of costa and middle of cell; dorsal streak dark fuscous, reaching near distal end of cell; tornus with a dark fuscous dot. Some variation in horn shape of signum in female genital.
Type material. CHINA: Holotype, Ƌ, Mt. Baotianman (33.52°N, 111.94°E), Neixiang County, Henan Province, 1350 m, 13.vii.1998, leg. Houhun Li, slide no. LTT12842. Paratypes: 2♀, same data as holotype, except 13, 14.vii.1998, slide nos. LTT12791, LTT12843; 1♂, 1♀, Mt. Fanjing (27.95°N, 108.62°E), Guizhou Province, 2100 m, 31.vii.2001, leg. Houhun Li and Xinpu Wang, slide no. LTT12333♀, LTT12334Ƌ.
Distribution. China (Guizhou, Henan).
Diagnosis. This new species is similar to A. (A.) mala and A. (A.) longa in having a relatively large wingspan, a yellowish-white head, and a yellowish-white dorsal band. Argyresthia (A.) decurtata can be separated from its two congeners by the forewing with the dorsal fascia reaching near the upper angle of the cell; in the male genitalia by the gnathos lacking the long thick apical setae and the phallus slightly curved at basal 3/5; and in the female genitalia by the narrowly band-shaped lamella postvaginalis. Argyresthia (A.) mala differs from A. (A.) decurtata in the forewing by the dorsal fascia reaching the costa, or disconnected near costa; in the male genitalia by the gnathos with four to nine long thick apical setae and a nearly straight phallus; and in the female genitalia by the rectangular lamella postvaginalis. Argyresthia (A.) longa differs from A. (A.) decurtata in the forewing by the dorsal fascia reaching the costa or near the costa; in the male genitalia by the gnathos covered with eight long thick apical setae and the straight phallus; and in the female genitalia by the lamella postvaginalis narrowly triangular on anterior half and linear on posterior half. Argyresthia (A.) mala and A. (A.) longa can be separated by the shape of the lamella postvaginalis as abovementioned. In addition, the ovipositor is extremely long in A. (A.) longa. Darker specimens of A. (A.) decurtata resemble the unicolorous “form” aerariella of A. (A.) conjugella and A. (A.) flavifusca, sp. nov. in forewing ground color, but A. (A.) decurtata has dark fuscous streaks on the forewing, which separates it from its two congeners, both of which lack such streaks on the forewings.
Etymology. The specific name is derived from the Latin decurtatus, meaning truncate, referring to the dorsal streak ending before the costa.
description: Published as part of Liu, Tengteng, Wang, Shuxia & Li, Houhun, 2017, Review of the genus Argyresthia Hübner, [1825] (Lepidoptera: Yponomeutoidea: Argyresthiidae) from China, with descriptions of forty-three new species, pp. 1-135 in Zootaxa 4292 (1) on pages 43-44, DOI: 10.5281/zenodo.827746