Meleonoma tenuicaulis, Zhu & Wang, 2025

Zhu, Xiaoju & Wang, Shuxia, 2025, Taxonomy of the facialis species-group of the genus Meleonoma Meyrick, 1914 (Lepidoptera: Autostichidae) from China, with descriptions of nineteen new species, Zootaxa 5637 (1), pp. 99-125 : 120-121

Meleonoma tenuicaulis sp. nov.

( Figs 20 , 42 )

Type material. CHINA, Yunnan: Holotype ♂, Qinlangdang (27.69°N, 98.27°E), Mt. Gaoligong, Nujiang , 380 m, 28.V.2017, leg. KJ Teng et al., slide No. ZXJ19390 .

Diagnosis. The new species is silimar to M. spicijuxta sp. nov. in the shape of the costal part of the valva in the male genitalia. The major differences lie in the sacculus with two apical processes and the elongate U-shaped juxta of the new species. In M. spicijuxta , the apex of the sacculus lacks apical processes, and the sub-rectangular juxta has a small spine-like process posterolaterally.

Description. Adult ( Fig. 20 ). Forewing length 5.0 mm.

Head with yellow scales, tipped with dark brown. Labial palpus lost. Antenna yellow; scape with dark brown scales dorsally; flagellum dark brown on dorsal surface except several basal flagellomeres yellow.

Thorax (worn) yellow; tegula dark brown, yellow distally. Legs yellow, with exceptions on ventral surface: femur and tibia of foreleg greyish black except tibia yellow apically, tarsus greyish black except yellow at base of basal tarsomere and at apices of basal two tarsomeres, tibia of midleg greyish black distally, tarsus greyish black except yellow at apices of basal two tarsomeres, tibia of hindleg with scattered greyish brown scales, tarsus with basal four tarsomeres greyish brown except yellow at apices. Forewing elongate lanceolate, with costal margin arched, apex narrowly rounded; ground colour yellow, with scattered dark brown and black scales; costal margin with an indistinct spot at base; costal spot dark brown, diffused posteriorly crossing anterior margin of cell; apical patch (worn) dark brown; several equally sized dark brown dots evenly spaced from distal part of costal margin along termen to tornus; discocellular spot black, touching with costal spot; fringe yellow. Hindwing and fringe dark brown.

Abdomen. Male genitalia ( Fig. 42 ). Uncus slender, hooked and pointed at apex. Gnathos sclerotized laterally, membranous anteriorly, exceeding anterior margin of tegumen. Tegumen arched, uniform in width, with a semicircular anterior emargination. Costal part of valva semielliptical, setose ventrally; costal band narrow, reaching before tip of costal margin; transtilla slender, clavate. Sacculus large, heavily sclerotized, narrow at base, gradually widened to apex; apex with two processes: dorsoapical process short, sub-triangular; ventroapical process longer and slenderer, spine-shaped distally. Saccus rounded. Juxta developed, elongate U-shaped, lateral arms narrowest at middle. Phallus slender, approximately 2/3 length of costal part of valva.

Female unknown.

Distribution. China (Yunnan).

Etymology. The specific epithet is derived from the Latin tenuis (thin) and caulis (stalk), referring to the slender phallus.

Figures

FIGURES 17−22. Adults of Meleonoma spp. 17, M. seorsispina sp. nov., ♂, holotype; 18, M. similicatenata sp. nov., ♂, holotype; 19, M. spicijuxta sp. nov., ♂, paratype; 20, M. tenuicaulis sp. nov., ♂, holotype; 21, M. tenuispina sp. nov., ♀, holotype; 22, M. verticalis sp. nov., ♂, holotype. Scale bars = 2.0 mm.

FIGURES 41−44. Male genitalia of Meleonoma spp. 41, M. spicijuxta sp. nov., holotype, slide No. ZXJ19372, 41a, enlarged gnathos, 41b, enlarged juxta, slide No. ZXJ18336; 42, M. tenuicaulis sp. nov., holotype, slide No. ZXJ19390; 43, M. tenuispina sp. nov., holotype, slide No. ZXJ19384; 44, M. verticalis sp. nov., holotype, slide No. ZXJ19381. Scale bars = 0.2 mm.