Palpifer chui Ignatev, Grehan & C. Mielke, sp. n.

(Figs 2, 6a, 6b, 10a, 11h, 12b, 13d, 13,e, 13f, 14b, 15b, 16b, 17b, 18b, 20b, 21b)

Palpifer pellicia (Daniel 1940)

Type material: Holotype ♂: (with the following labels separated by forward slashes [no collection date]): Lingping [ Guangxi], Südchina, H Höne / Palpifer pellicia Smh. Det F. Daniel / ZFMK Lep 155605 / ZFMK dissection 148052. / Palpifer chui ♂: Ignatev, Grehan & C. Mielke des. 2023. Deposited in the collection of ZFMK .

Diagnosis. The subequal length of the valva digitiform branch and blade distinguishes P. chui sp. n. (Fig. 14b) from the Malaysian P. hylandae Grehan & Mielke, 2019 (Fig. 22b) and P. climoi sp. n. (Fig. 14d), each with a shorter digitiform branch, and from the Himalayan P. murinus (Moore, 1879) that lacks a digitiform branch (Fig. 22d). Within the cluster of species with a subequal digitiform branch, P. chui sp. n. has a medially oriented and wide pseudoteguminal arms apex that distinguishes it from P. boonei of Laos, P. hylandae, and the Himalayan P. sexnotatus and P. falkneri, that have a narrow pointed pseudoteguminal arms apex (Fig. 22). The medially oriented and broad apex of P. chui sp. n. (Fig. 20b) distinguishes this species from P. nielseni sp. n. with an anteriorly oriented and narrowed pseudoteguminal apex (Fig. 20a). These two species also differ from each other by the posteriorly narrowed medial ridge in the fultura inferior of P. chui sp. n. (Fig. 21c). The short, deep anterior convex lateral margins of the fultura inferior of P. chui sp. n. (Fig. 21b) distinguish this species from P. hopponis with a broad and shallow anterior concave margin (Fig. 21b).

Description. Male. Wingspan (HT): ~ 27 mm; forewing length: 11 mm, width: 5 mm; hindwing length: 9 mm, width: 4 mm.

Head (Figs 6a–b, 10a): As for P. nielseni sp. n., except that ocular-antenna scales were not observed due to disturbed scale condition of specimen. Labial palps not dissected.

Thorax: Body and legs (Fig. 12b) as for P. nielseni sp. n. Forewing with white outer discal spot (Fig. 11h).

Pregenital abdomen (Figs 13d–f): Sternum I removed intact, membranous (Fig. 13e). Hook-shaped spur on dorsal brace of tergosternal sclerite is an artefact of flattening the integument for imaging (Fig.13d); sternum II (Fig. 13e) proportionately broader with a more strongly curved lateral ridge than in P. nielseni sp. n.

Genitalia (Figs 14b, 15b, 16b, 17b, 18b). Medially oriented apex of pseudoteguminal arms broad, rounded, without strong distal sclerotization (Fig. 20b). Fultura inferior with medial ridge slightly coiled and narrowing postero-dorsally (Fig. 21b).

Habitat and Phenology. Unknown. No collection date and location not precise.

Distribution. Known from type locality only (Fig. 25).

Etymology. Named for Hong-Fu Chu, a leading entomologist of China who published extensively on new species and genera of Chinese Hepialidae .