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

(Figs 1a, 1b, 1c, 1d, 5a, 5b, 8, 9a, 10d, 11a, 11e, 11f, 11g, 12a, 13a, 13b, 13c, 14a, 15a 16a, 17a, 18a, 20a, 21a)

Type material. Holotype: ♂: Kautun [Guadun] (2300.m) 27,40n. Br. 117,40ö. L. J. Klapperich. 27. 5. 1938 (Fukien) [China, Fujian] / Sammlung Daniel / MWW 36.331 / Holotypus, Palpifer nielseni ♂, Ignatev, Grehan & C. Mielke des. 2023. Deposited in collection of MWW.

Paratypes: 2 ♂: Kautun [Guadun] (2300 m) 27,40n. Br. 117,40ö. L. J. Klapperich. 27. 5. 1938 (Fukien) [Fujian province] / Palpifer pellicia Sroh. Det. F. Daniel / ZFMK Lep148051, Lep148050. 1♂: Shaowu—Fukien [Fujian province] (500 m) J. Klapperich. 10. 5. 1937 / ZFMK Lep148049. All depostited in the collection of ZFMK.

Diagnosis. The subequal length of the valva digitiform branch and blade of the male genitalia distinguishes P. nielseni sp. n. 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 sharing a subequally long digitiform arms and blade, the anteriorly oriented and narrowed rounded pseudoteguminal apex of P. nielseni sp. n. (Fig.20a) differs from the medially oriented and broad apex of P. chui sp. n. (Fig. 20b). The two species also differ by tapered medial ridges in the fultura inferior of P. chui sp. n. (Fig. 21b). The rounded pseudoteguminal apex of P. nielseni sp. n. separates the species from the Laotian P. boonei Grehan & Mielke, 2019, P. hylandae, P. sexnotatus (Moore, 1879), P. falkneri Viette, 1968 that have a narrowly pointed pseudoteguminal arm apex (Fig. 22). The strongly sclerotized and anteriorly oriented pseudotegumen arms P. nielseni sp. n. (Fig. 20a) differentiate this species from the Taiwanese P. hopponis Matsumura, 1931 (Fig. 20c).

Description. Male. Wingspan (HT): ~ 22 mm; forewing length: 9 mm, width: 4 mm; hindwing length: 8 mm, width: 3 mm. External colour and pattern given below for specimen L148049 (ZMFK) in best condition.

Head: (Figs 5a–b, 9a, 10d): Scales grey, piliform; eye tuft scales yellowish brown (Fig. 5b). Eyes prominent, partially obscured by surrounding scales. Antenna filiform with 33 flagellomeres (WMW 36.331, ZFMK L148051), annuli covered with numerous sensilla chaetica (Fig. 10d); scape barrel shaped, covered with piliform scales; pedicel ovoid and subequal to flagellomeres. Palpomeres covered with piliform scales; three segmented, second palpomere longest—about twice basal palpomere; distal palpomere small, ovoid and positioned apically (Fig. 9a).

Thorax: Scales of body and legs piliform, coloured as for head. Legs (Fig. 12a); pro-, meso-, and metalegs length subequal, tibial scales, about half length of tibia, dorsal scales of tarsi about twice segment length, ventral tarsal scales short, epiphysis and arolium present.

Wings. Dorsal and ventral ground colour greyish-brown (Fig. 1b, 11e–g). Forewing with prominent, yellowish-white stigma (‘great white spot’) at base of anterior discal cell, two yellowish white spots near wing base near CuP and A, black marginal spot on posterior margin between CuA 2 and CuP, and two small yellowish white spots between R and Rs near apex (faintly visible in HT specimen only); Hindwing with pale yellowish brown ground colour between R and costa, outer margin with yellowish-white patch on fringe and outer margin between Rs3- M 1 veins. Costal margin nearly straight, apex, outer and dorsal margins forming a continuous curve, tornus not discernable. Venation hepialine (sensu Dumbleton 1966), forewing with Sc1 present, CuP very short beyond cross veins A-CuA 2; Hindwing Sc1 absent, single anal vein present.

Pregenital abdomen: (Fig. 13a–c). Coloured as for thorax, anterior segments dorso-ventrally taller, and segments narrowing posteriorly. Tergosternal sclerite narrow; tergosternal bar curving dorso-anteriorly to junction with lateral tergal brace with no discernible central region, angled antero-ventrally to form an acute angle with lateral tergal arm, latter subequal length to tergosternal bar; dorsal tergal merging with anterior ridge of tergum II anterior to tuberculate plate. Abdominal segments lightly sclerotized; tergum II with anterior ridge fused across median, lateral ridge extending posteriorly from ventral corner of lateral tuberculate plate, but not reaching posterior margin; sternum II subrectangular, lateral arms broad, laterally edged with sclerotized ridge angled medially towards posterior; sternum III subsquare; tergum VIII subrectangular, narrowing posteriorly, four times longer than wide; sternum VIII subtriangular with concave lateral edges and digitiform shaped posterior half (Fig. 13c).

Genitalia (Fig. 14a, 15a, 16a, 17a, 18a, 20a, 21a). Tergum IX membranous (sclerotized tergal lobes absent). Tegumen fused with pseudotegumen, boundary indistinct. Pseudotegumen rim bordering anogenital field with, densely sclerotized, sub-equal, and laterally curved postero-ventral and postero-medial spines (Figs 14a, 16a); pseudoteguminal arms (antero-ventral margin of anogenital field) not fused across median, distally rounded and strongly sclerotized, angled medially (Fig. 20a). Valva with posterior elongate digitiform arm, curving medially, apex expanded as a flattened lobe covered with numerous short setae, setae also extending basally along inner surface; and broad anterior flange, distally narrowing to blunt apex, medial surface with setae over approximately anterior half. Fultura superior sclerotized, forming a ‘V’ shape, articulating dorsally with pseudotegumen and ventrally with fultura inferior; latter forming a vertically elongate, tongue-like sclerite, length almost double maximum basal width, laterally convex; medial and posterior sclerotization forming an inverted ‘T’. Phallus membranous. Saccus with broadly U-shaped anterior margin, posterior margin almost straight.

Habitat and Phenology. Habitat unknown, presumed to be forest or adjacent agricultural environments as known for some other species (Grehan & Mielke 2019). Specimens were collected in May, which corresponds to late Spring emergence, and precedes the highest rainfall between June and August for Fujian province (Zhao e t al. 2017).

Distribution. Eastern China, Fujian province (Fig. 25).

Etymology. Named for Australian lepidopterist John Nielsen, for his research support and collaborations on Hepialidae .