Helcystogramma flavifuscum, Li & Zhen, 2011
treatment provided by
Helcystogramma flavifuscum sp. nov.
Helcystogramma flavifuscum sp. nov. is similar to H. perelegans (Omelko et Omelko) , but differs from the latter in the forewing lacking dark silvery-grey markings, with yellowish-brown metallic lustre instead of purplish-blue metallic lustre; the uncus narrowed at two-fifths length (about two-thirds width at base), distal three-fifths parallel sided, slightly acute posterolaterally, the valva narrowest at one-third length (about one-half width at base), then broadened gradually to bluntly rounded apex in the male genitalia.
Adult ( Figure 8A View Figure 8 ). Wingspan 10.5 mm. Head greyish-yellow, frons white. Antenna with scape dark brown on dorsal surface, white on ventral surface; flagellum alternately dark brown and greyish-brown on dorsal surface, ochreous on ventral surface. Labial palpus with second segment about twice length of diameter of eye, about equal to length of third segment; first and second segments silvery-grey, mottled white on inner surface; third segment dark brown on dorsal surface, yellowish-white on ventral surface. Thorax and tegula yellowish-brown. Forewing with costal and dorsal margins nearly parallel, apex pointed, termen concave below apex, then upright; ground colour greyish-brown, with yellowish-brown metallic lustre; area along and below fold yellowish-brown; costal margin with short white streaks at two-fifths length and threefifths length, from beyond three-fifths length to before apex with inverted triangular dark brown mark extending beyond end of cell; two fasciae terminally, inner one shining silvery-grey, outer one yellowish brown above apex, yellow with four longitudinal dark brown streaks below apex; fringe greyish-brown on termen, yellowish-white at tornus, basal half white and distal half greyish-brown at apex. Hindwing and fringe grey. Legs with femora yellowish-white, tibiae and tarsi dark brown, tarsomeres white apically on outer surface, greyish-white on inner surface.
Uncus slightly narrowed at two-fifths length (about two-thirds width at base), distal thre-fifths parallel marginal, posterior margin nearly straight, slightly acute laterally; about one-half length of valva ( Figure 11F View Figure 11 ). Gnathos about three-fifths length of valva; culcitula nearly inverted trapeziform, bluntly rounded posteriorly. Valva narrowest at one-third length (about half width at base), then broadened gradually to bluntly rounded apex, shorter than tegumen–uncus complex. Vinculum with lobes concave near base of inner margin, nearly triangular apically. Aedeagus nearly oval in basal two-fifths, then narrowed gradually to near two-thirds, clubbed in distal one-third. Eighth tergite somewhat semioval, deeply concave anteriorly ( Figure 10E View Figure 10 ).
The specific name is derived from the Latin prefix flav-, meaning yellow, and the Latin fuscus, meaning brown, referring to the forewing with yellowish-brown metallic lustre.
The triannulella group
The species group is characterized by the absence of the ocellus, the ciliate antenna, the labial palpus with third segment about equal to or slightly shorter than second, the lack of the hair pencil from the mesothoracic anepisternum; the eighth tergite concave anteriorly, the uncus nearly oblong, slightly narrowed near base, the gnathos slender, sharp apically, the vinculum with lobes strongly sclerotized in distal part on inner margin and forming a heart shape, distally directed obliquely inward, and widened apically, the saccus narrowly elongate ( Figure 16A View Figure 16 ), and the aedeagus longer than valva, with basal half ellipsoidal, hooked at apex or with a small process at subapex in the male genitalia; the antrum sclerotized, with short spines except median portion, the ductus bursae membranous, and the ductus seminalis arising from posterior part of the corpus bursae in the female genitalia.
The triannulella group includes H. arotraeum ( Meyrick, 1894) , H. fuscomarginatum Ueda, 1995 , H. lutatella (Herrich-Schäffer, 1854) , H. triannulella (Herrich- Schäffer, 1854) and H. brevinodium sp. nov in China. Helcystogramma lutatella and H. triannulella have similar male genitalia, but they can be easily separated by the structures of the female genitalia, and by the darker ground colour of the forewing in H. triannulella .
The triannulella group in China is mainly distributed in the central and east parts (Figure 2). Some are found in northern Xinjiang Uygur Autonomous Region, but seldom in southwest.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.