Yufengus atrophaneuroides Lin, Lin & Epstein, 2025

Yufengus atrophaneuroides Lin, Lin & Epstein sp. nov.

Figs 1–8 View Figures 1–8 , 13 View Figures 13–16 , 14 View Figures 13–16 , 17 View Figures 17, 18 , 19 View Figures 19–22 , 20 View Figures 19–22 , 23–34 View Figures 23–40 , 41–51 View Figures 41–58

Type materials.

Holotype. Taiwan • 1 ♂; New Taipei City, Wulai, Xinfu Rd. ; 24.8259, 121.5240; alt. 380 m; 28 Feb. 2022; Y. C. Lin, R. J. Lin, C J. Hung & H. Chang leg.; reared from Oreocnide pedunculata , pupated 21 Mar. 2022, emerged 17 Apr. 2022; HSU 22 B 39 M (Figs 1 View Figures 1–8 , 2 View Figures 1–8 ) GoogleMaps .

Paratypes. Taiwan • 1 ♂; New Taipei City, Wulai, Xinfu Rd. ; 24.8259, 121.5240; alt. 380 m; 28 Feb. 2022; Y. C. Lin, R. J. Lin, C. J. Hung & H. Chang leg.; reared from Oreocnide pedunculata , pupated 25 Mar. 2022, emerged 23 Apr. 2022; HSU 22 B 39 M (Figs 7 View Figures 1–8 , 8 View Figures 1–8 , 13 View Figures 13–16 , 14 View Figures 13–16 , 17 View Figures 17, 18 , 19 View Figures 19–22 ) GoogleMaps • 1 ♂; New Taipei City, Wulai, Xinfu Rd. ; 24.8259, 121.5240; alt. 380 m; 28 Feb. 2022; Y. C. Lin, R. J. Lin, C. J. Hung & H. Chang leg.; reared from Mussaenda parviflora , pupated 9 Mar. 2022, emerged 31 Mar. 2016; HSU 22 B 40 M (Figs 3 View Figures 1–8 , 4 View Figures 1–8 ) GoogleMaps • 1 ♀; New Taipei City, Wulai, Xinxian ; 24.8355, 121.5274; alt. 220 m; 31 Mar. 2016; M. X. Luo & H. P. Lu. leg.; reared from Smilax bracteata , emerged 4 May 2016; GenBank: MK 128293 View Materials ; HSU 16 C 67 M (Figs 5 View Figures 1–8 , 6 View Figures 1–8 , 20 View Figures 19–22 ) GoogleMaps .

Diagnosis.

See under Yufengus above.

Description.

Male (Figs 1–8 View Figures 1–8 , 13 View Figures 13–16 , 14 View Figures 13–16 , 17 View Figures 17, 18 ). Head: frons hairy, brown with yellow scaling; eyes semioval, black; antenna bipectinate from base to apex, medial side of antenna protrusions shorter than the lateral side; labial palpus upcurved with the apex pointing dorsally, covering dark brown scales dorsally and yellow scales ventrally, with the 3 rd segment longer than 1 / 3 of 2 nd segment (Fig. 14 View Figures 13–16 ); proboscis present (Fig. 13 View Figures 13–16 ). Thorax: dark brown, with long, yellow hairs laterally and posteriorly near abdomen; legs brown, banded with yellow on tarsi (Fig. 7 View Figures 1–8 ), midleg with one pair of tibial spurs, hindleg with two pairs of tibial spurs, each pair of unequal length (Fig. 8 View Figures 1–8 ). Forewing: 8.16–8.79 mm long ( x ̄: 8.44 ± 0.32 mm, n = 3). Upperside ground color dark brown, a reddish-brown spot surrounded by black at apex, three black patches on discal cell, discal area, and postdiscal area. Four white spots from inner margin to discal cell (latter two sometimes invisible) (Figs 1 View Figures 1–8 , 3 View Figures 1–8 ), fringe with dark-brown scales. Underside ground color dark brown, broadly pale grey along inner margin, a reddish-brown spot surrounded by black at apex. Forewing venation: Rs 2 and Rs 3 on common branch originating from Rs 1 near discal cell; Rs 4 originating from discal cell; MS bisecting discal cell; 1 A + 2 A with basal fork. Hindwing: upperside dark brown; fringe with contrasting pale-yellow scales, becoming mostly black near tornus. Underside similar to upperside. Hindwing venation: MS present in discal cell; a very short cross vein between R and RS at the proximal third of the wing, inside the discal cell; RS and M 1 meet at outer end of discal cell; CuP, 1 A + 2 A, and 3 A present as typical in Limacodidae . Abdomen: dark-brown dorsum, yellow in posterior half of ventrum.

Female (Figs 5 View Figures 1–8 , 6 View Figures 1–8 , 50 View Figures 41–58 , 51 View Figures 41–58 ). Similar to male, but larger (forewing 11.14 mm long, from base to apex); antenna filiform; ground color of wing brown, hindwing with a small dark-brown spot at apex, fringe of hindwing brown with dark scales throughout; the 5 th tarsomere with a triangular, recessed pad bearing sensilla and spinules (Fig. 51 View Figures 41–58 ); abdomen brown ventrally.

Male genitalia (Fig. 19 View Figures 19–22 ). Uncus narrow throughout and curved slightly downward at apex. Gnathos absent. Tegumen and vinculum wider than the uncus. Juxta roughly triangular, slightly sclerotized, and setose. Valva elongate, round at apex and with short hairs on inner surface and slightly narrow at base; medial portion with sclerotized process with distal sawteeth. Saccus short. Phallus straight, tubular.

Female genitalia (Fig. 20 View Figures 19–22 ). Papillae anales flat, drop-shaped; anterior apophyses short, digitate, posterior apophyses about two times as long as anterior apophyses. Ductus burse membranous and straight. Corpus bursae ovate, about two-thirds length of ductus burse; signum with spines: two large and a few small ones.

Immature stages (Figs 23–34 View Figures 23–40 , 41–49 View Figures 41–58 ). Egg (Fig. 23 View Figures 23–40 ): flat oval, 1.92–2.00 mm in long axis (1.97 ± 0.05 mm, n = 3) and 1.22–1.30 mm in short axis (1.26 ± 0.04 mm, n = 3). First instar larva (Fig. 24 View Figures 23–40 ): yellow ground-colored body with broken orange stripes on mid-dorsum and dorsolateral lines. Prothorax (T 1) without tubercles and T 2 and T 3 each have three tubercles on each side, one D tubercle on A 1, two tubercles — D and SD — on A 2 – A 9; each tubercle has three setae. Two L setae on each segment. Early to mid-instar larvae (Figs 25–28 View Figures 23–40 ): ground color of body yellow to white; some individuals with black patches on the range of T 3 – A 1 and A 3 – A 5 (Fig. 26 View Figures 23–40 ); some individuals in the stage before the final instar (Fig. 28 View Figures 23–40 ) with the slightly visible color of the final instar. Final instar larva (Figs 29–32 View Figures 23–40 ): 12.10–12.48 mm in length (12.3 ± 0.19 mm without spine length, n = 3), 4.93–6.69 mm in width of A 3 (5.93 ± 0.9 mm without spine length, n = 3). Head dark brown; labrum with multiple spinules anteriorly and laterally (Fig. 42 View Figures 41–58 ); stemmata with gaps of approximately the width of a stemma between stemma 1 and stemma 2, and between stemma 5 and stemma 6 (Fig. 43 View Figures 41–58 ); has only one seta (encircled by stemmata); spinneret brush-like with apex tapered (Fig. 44 View Figures 41–58 ). Body slug-like, ground color black. Prothorax (T 1) white with no tubercles; mesothorax (T 2) with two single black D tubercles, one single black SD tubercle, and two short white L tubercles; metathorax (T 3) with a branched D tubercle (two black branched parts on a quadripartite base, Fig. 32 View Figures 23–40 ), and two single black SD tubercles, and two short white L tubercles. First abdominal segment (A 1) with only a branched D tubercle. Abdominal segments with same D tubercles as A 2 – A 8 as A 1 but have one single black SD tubercle on each segment, two short white outgrowths for L of A 2 – A 8. The longest D tubercle is on A 4 and there are red patches on the tubercle apices of A 5 – A 8, especially distinct on A 6 and A 7; one long tubercle for D and one white tubercle for L of A 9. All tubercles bear numerous plumose setae (Fig. 46 View Figures 41–58 ) and a single long bristle with tactile function, and those for D and SD can be easily detached when touched. The pretarsal claw of the thoracic leg (Fig. 45 View Figures 41–58 ) is wide proximally, hook-like distally, with hair-like setae. Cocoon (Figs 33 View Figures 23–40 , 34 View Figures 23–40 ): spheroid, 8.36– 6.80 mm in long axis (7.57 ± 0.78 mm, n = 3) and 6.96– 5.63 mm in short axis (6.19 ± 0.69 mm, n = 3), brown, with silk blending setae of final instar and forming a thin outer membrane. Pupa (Figs 47–49 View Figures 41–58 ): thin cuticle, pupal eyepiece with a fracture line, maxilla without maxillary extension, pupal frons rough and shagreened, dorsum of abdominal segments with patch of spicules along anterior margin.

Etymology.

The specific name atrophaneuroides is derived from the swallowtail genus Atrophaneura Reakirt (Papillionidae) and the Latin suffix - oides, which means “ - like ”, because the black and red outgrowths of the final instar is reminiscent of Atrophaneura larvae. The species epithet is a compound descriptive name comprising an adjective combination with the ending of the second name in masculine form to agree in gender with the generic name.

Distribution.

Yufengus atrophaneuroides is usually found from montane areas at low altitude in Taiwan.

Biology.

Yufengus atrophaneuroides is polyphagous. Its larvae have been found on Oreocnide pedunculata (Shirai) Masam ( Urticaceae ) ( HSU 22 B 39 M ), Mussaenda parviflora Miq. ( Rubiaceae ) ( HSU 22 B 40 M ), Smilax bracteata C. Presl var. verruculosa (Merr.) T. Koyama ( Smilacaceae ) ( HSU 16 C 67 M , 22 B 42 M), and Maesa perlaria (Lour.) Merr. var. formosana (Mez) Yuen P. Yang ( Myrsinaceae ) ( HSU 22 B 41 M ). According to Taiwan Moth Information Center ( https://twmoth.tbri.gov.tw), established and maintained by Taiwan Biodiversity Research Institute, Yufengus larvae have been found from January to June. Based on rearing data, larvae reared in captivity developed directly, with the pupal stage around a month. The cocoons (Fig. 33 View Figures 23–40 ), similar to Phrixolepia (Fig. 40 View Figures 23–40 ), do not encorporate the tubercles from the prepupa as in Phobetron (see figure in Epstein et al. in press). These observations suggest there are multiple generations of Y. atrophaneuroides annually. Eggs are laid singly (Fig. 23 View Figures 23–40 ), similar to Phrixolepia (Fig. 35 View Figures 23–40 ) and other gelatines (Epstein et al. in press).

Remarks.

The final instar larvae of Y. atrophaneuroides shows marked variation in tubercle apices from different locations. For example, there is no white patch on larvae collected from New Taipei City (Fig. 29 View Figures 23–40 ); however, there are little white patches on larvae from Hualien County, eastern Taiwan (Figs 30 View Figures 23–40 , 31 View Figures 23–40 ). According to the “ Taiwan Moth Information Center ”, these white patches are bigger on the larvae from Hsinchu County (collecting number: 497121; https://twmoth.tbri.gov.tw/peo/FBMothInfo/497121) than that from Hualien County; furthermore, the largest white patches occur on the larvae from Pingtung County (collecting numbers: 240751 and 339953; https://twmoth.tbri.gov.tw/peo/FBMothInfo/240751 and https://twmoth.tbri.gov.tw/peo/FBMothInfo/339953, respectively). Whether this represents discrete or continuous variation requires additional investigation. Another from Xinxian, Wulai, Taiwan on 15 Dec. 2021 by David Tai may be an earlier instar of Y. atrophaneuroides ( https://twmoth.tbri.gov.tw/peo/FBMothInfo/466895).

The early instars of Y. atrophaneuroides closely resemble some mealybugs such as Phenacoccus madeirensis Green, 1923 . Many mealybugs are covered with white, powdery or mealy wax secretion on the body, which are believed to protect them from predators ( Gullan and Kosztarab 1997). According to a mealybug study in Taiwan ( Tsai 2011), P. madeirensis is widely distributed and polyphagous, and it co-occurs with Y. atrophaneuroides in New Taipei city. In the field, mealybugs have also been found in the same area where Y. atrophaneuroides occurs. Hence, the possibility of mimicry cannot be excluded.

There may be additional species in Yufengus , as suggested by larval photographs available online from outside Taiwan. For example, one is observed in Gunung Mulu National Park, Sarawak, Malaysia, at 131 m on 29 Sept. 2012 by Bernard Dupont ( https://www.inaturalist.org/observations/85512375).