male, China, Hainan, Mt. Diaoluo, 109.87°E, 18.72°N, 900 m, 23.V.2014, leg. Li-Jun Xu & Dan Xu, pinned, slide number XD15056. Original label: “Hainan, Diaoluo Mountain, vocational village, 900 m, 23.V.2014, Li-jun Xu & Dan Xu”.

1 female, same data as holotype, slide number XD15050.

This species can be distinguished by the wingspan of 33.0–35.0 mm (Fig. 1); the brown patch near base of the labial palpus (Fig. 2), the male antenna with ventral cilia nearly as long as the diameter of flagellomere; in the male genitalia by the thick finger-like gnathos bearing long setae on the apex (Fig. 3), the phallus with a dorsally protruding sclerotized structure with a slant nailhead-like apex, and a long thick needle-like cornutus stretching out from a cluster of spicular cornuti near apex (Fig. 4).

Figures 1–4. 

Patania clava sp. n., Holotype. 1 Adult 2 Head 3 Gnathos 4 Cornuti.

Adult (Figs 1–2). Wingspan 33.0–35.0 mm. Body pale yellow. Antenna pale yellow dorsally, orange ventrally. Male antenna with ventral golden cilia nearly as long as the diameter of flagellomere. Labial palpus upturned, pale yellow with a brown patch near base. Maxillary palpus small, pale yellow. Patagium pale yellow, with large fuscous spots. Tegula pale yellow and fuscous. Forewing pale yellow, with fuscous lines, spots and patches; a spot at inner edge near basal line; a large elliptical patch between basal line and antemedial line; orbicular stigma distinct; discoidal stigma reniform, its posterior part overlapping postmedial line partly; a large patch outspread between discoidal stigma and inner margin; postmedial line oblique inward from costa, excurved vertically from M₁ to CuA₂, with a distinct punctiform pattern between M₂ and CuA_2, then sharply incurved along CuA₂ as an indistinct line before curving towards the dorsum; a large patch between anterior half of postmedial line and marginal line, marginal line consisting of a line of spots. Hindwing pale yellow; discoidal stigma brown; a brown slant stripe below end of discal cell and a pale brown fuzzy band beyond it; postmedial line oblique inward from costa, excurved vertically from M₁ to CuA₂, with a distinct punctiform pattern between M₂ and CuA₂, then sharply incurved along CuA₂ as an indistinct line before curving towards the dorsum; marginal line fuscous; brown blot near apical angle. Fringes of forewing and hindwing white at base, pale brown terminally. Fore coxa yellow, with two big black spots; femur yellow except for black distal end; tibia pale yellow with distal half black, tibial comb orange. Mid femur white, with a black spot near centre; tibia pale yellow, black distally, a black spot near the base. Hind femur white, with a brown spot near the distal end; tibia white, somewhat pale brown near the base. Abdomen orange dorsally; anterior edge of 2^nd segment with two lateral black spots flanking the centre, 7^th segment with a big black spot separated slightly at the center; pale yellow ventrally.

Male genitalia. (Figs 3–4, 9). Uncus triangular, blunt on posterior margin. Gnathos thick finger-like, apex circularly widened and dorsally studded with long thin simple setae. Valva ligulate. Fibula near base of valva, flat, triangular, with long dense setae. Transtilla triangular, connected medially, with sparse setae. Saccus oblong, with the anterior apex rounded. Juxta ovate. Phallus cylindrical, with a dorsally protruding sclerotized structure with a slant nailhead-like apex, a long thick needle-like cornutus stretching out from a cluster of spicular cornuti.

Female genitalia. (Fig. 10). Apophysis anterioris about 1.5 times length of apophysis posterioris, triangular extension near base unilaterally. Ductus bursae about 4 times length of corpus bursae, middle ductus bursae widened, area posterior of widening slightly sclerotized; ductus seminalis originating at posterior end of ductus bursae. Corpus bursae elliptical, without signum. Both ductus bursae and corpus bursae densely studded with tiny granules.

The specific name is derived from the Latin clavus (nail), in reference to the nail head-like apex of sclerotized structure of the phallus.

This species is only known from the Diaoluo Mountain of Hainan Island, China.

Unknown except that the moths fly late May and are attracted to light. The habitat in which this species has been collected is located at an altitude of 900 m. The vegetation of the habitat is a blend of shrubs, conifer trees and broad leaved trees.

The most similar congener to P. clava sp. n. is Patania iopasalis (Walker, 1859). However, the wingspan of P. iopasalis is smaller with 21.0–30.0 mm (Fig. 5); the labial palpus has no brown patch near the base but a big brown patch near the apex (Fig. 6), the male antenna has ventral cilia about one-fourth the length of the diameter of flagellomere; in the male genitalia the short broad sheet-like gnathos lacks setae on the apex (Fig. 7), the phallus has an ovate sclerotized structure protruding from apex, and a long thick needle-like cornutus is embedded in a cluster of spicular cornuti (Fig. 8). Patania clava sp. n. is also similar to Patania obfuscalis (Yamanaka, 1998) in appearance. The latter can, however, be distinguished by its serrated postmedial line of forewing; in the male genitalia by the middle costa slightly inflated and bearing a cluster of setae, the vestigial gnathos, the board-like sclerotized, apically tapering structure protruding from apex, and a short broad thorn-like cornutus near a cluster of spicular cornuti.

Figures 5–8. 

Patania iopasalis (Walker). 5 Adult 6 Head 7 Gnathos 8 Cornuti. Slide number XLJ14083.

Figures 9–10. 

Genitalia of Patania clava sp. n. 9 Male, Holotype a Without phallus b Phallus, Holotype 10 Female, paratype.

The new species is only known from Diaoluo Mountain of Hainan Island at present. Patania iopasalis is widely distributed in south Asia, southeast Asia, east Asia, including Hainan Island, China, the Caroline Islands, New Guinea, Australia and Guatemala (Hampson 1896, 1898; Klima 1939; Xu 2015). Patania obfuscalis is distributed in Nepal and some areas of China, excluding Hainan Island.