Neptis reducta, Fruhstorfer, 1908

Hsu, Yu-Feng, Lu, Chen-Chih, Huang, Hang-Chi, Liang, Jia-Yuan & Huang, Chia-Lung, 2019, Immature stages of Neptis reducta Fruhstorfer, 1908 (Lepidoptera, Nymphalidae Neptini): morphology, ecology and food specialty, Zootaxa 4688 (4), pp. 569-577 : 572-575

Morphology of Neptis reducta immatures.

Ovum ( Fig. 7 ): Approximately 0.10± 0.05mm in diameter, 0.96± 0.06 in height (n=7). Spherical with bottom flattened, surface of chorion glossy, sculptured with hexagonal frames, possessing spines.

Larva ( Figs. 8–12 ). 1 st instar ( Fig. 8 ). Body length up to 3.60± 0.24mm (n = 5). Head nearly rounded, brown ornamented with a few pale dots. Body cylindrical, bearing transparent setae, Legs brown. Paired fleshy tubercles present on T2, T3, A2 and A8, with thoracic ones more prominent. Body dark brown mottled with white markings. Spiracles brown. 2nd instar ( Fig. 9 ). Body length up to 5.53± 0.63mm (n = 5). Body covered with hair-like setae with base enlarged. Setae transparent or tinged with brown. Head shield-like, with a pair of dorsal conical bumps, sculptured with fine, dark brown concave pits, brown with lateral white lines. Tubercles on T2, T3, A2 and A8 further developed, turning conical in shape, bearing many setae. Body pale brown with dark portion laterally. Spiracles brown. 3rd instar ( Fig. 10 ). Body length up to 10.49± 1.33mm (n = 8). Paired prominent processes present on T2, T3 and A8, with length T3> T2> A8. Head similar to 2nd instar, but dorsal processes more prominent, conical. Body surface covered by short, simple setae. Body pale brown, with dark brown, lateral patches from A5 to caudal end. Three dark green or brown chevrons present dorsally from A2 to A5. Spiracles dark brown. 4th instar ( Fig.11 ). Body length up to 14.39± 1.83mm (n = 6). Morphology similar to that of 3rd instar, but T3 processes thicken with base swollen, strongly bent and pointing ahead. T2 processes reduced to small bumps. A8 processes short, rod-like. Transverse, dark stripes present on T2 and T3 dorsally. Head with dorsal processes thicken. Greenish white spots arranged into a letter “L” present laterally. 5th (final instar) ( Fig.12 ). Body length up to 19.00± 0.90mm (n = 5). Morphology similar to that of 4th instar, but T3 processes extending to head, dorsal processes shorten, bump-like. Pupa ( Figs. 13–14 ): Body length 15.31± 0.79mm; width of A3 6.85± 0.46mm (n = 8). Ungirdled. Roughly cylindrical but somewhat flattened dorsoventrad, ridged dorsomesad and along termen and dorsum of wing. A pair of small horns on head. Antenna reaching posterior margin of A4. A conical spine at wing base. Paired spines at A2. Paired, dorsal, silver spots on T1, T2, T3 and A1 dorsally. Body of silver shine with brown markings. Spiracle dark brown.

Diagnosis. Although larva of N. reducta is a specialist on A. aspera , the plant was found utilized by larvae of two other Neptis species, namely, N. sappho and N. nata . The larvae and pupa of N. reducta ( Figs. 8–12 , 13–14 , 19–23 ) may be distinguished from those of N. nata ( Figs. 15–16 , 24–28 ) and N. sappho ( Figs. 17–18 , 29–33 ) by the following characters: 1) processes on vertex of larval head are thick and short in N. reducta in all instars except first instar ( Fig. 19–23 ), whereas they are slender and long in N. nata ( Fig. 24–28 ) and N. sappho ( Fig. 29–33 ); 2) lateral greenish white spots present in A7 and A 8 in final instar larva of N. nata and N. sappho (see p. 443, Lu & Chen, 2014), but only in A 7 in final instar larva of N. reducta ( Figs. 12 ); 4) A2 processes are prominent, as conical, spine in final instar larva of N. sappho (see p. 443, Lu & Chen, 2014), whereas they are reduced, bump-like in N. nata (see p. 443, Lu & Chen, 2014) and N. reducta ( Fig. 12 ); 3) T2 processes of final instar larva are strongly curved, pointing anteriad in N. reducta ( Fig. 12 ), whereas they are nearly straight, pointing dorsad in N. nata and N. sappho (see p. 443, Lu & Chen, 2014); 4) the ground color of pupa is of silvery shine in N. reducta ( Figs. 13–14 ) and N. nata ( Figs. 15–16 ), but it is pale brown tinged with yellow in N. sappho ( Figs. 17–18 ); 5) medial ridge on thorax of pupa is weakly produced and curved in N. reducta ( Fig. 14 ), whereas it is strongly produced into an angle in N. nata and N. sappho ( Fig. 16, 18 ).

Bionomics. Although the hostplant A. aspera is a tree that may grow up to 20m in height ( Fu et al. 2003), immatures of N. reducta were only found from young trees, at position 71.8–299.2 cm (170.1± 65.1cm, n = 25) above the ground. Female of Neptis reducta was observed sitting on mature leaf of the hostplant with head in the direct of the trunk for oviposition, bending abdomen depositing an egg at the tip of the leaf. All eggs found in the wild were also at upperside of the leaf tip ( Fig. 7 ). Young larva stays at the tip of a leaf, on upperside, constructing “curtain”-like feeding artifact by devouring lamina into leaflets connected by thin veins ( Figs. 8–9 ). Older larva rests on distal part of a leaf, with head directing toward the trunk of the hostplant ( Fig. 12 ). Pupa hangs under mature leaf ( Figs. 13–14 ).

Vouchers. TAIWAN: TAIZHONG (= TAICHUANG) CITY , 1♂, Heping, Defulan Trail , ca 600 m, XII. 29. 2012, reared from Aphananthe aspera , emgd. I. 25. 2013, HSU 12 M21 (C. C. Lu), 2♂ 1♀, same locality, XI. 12. 2018, reared from A. aspera , emgd. XII. 25/27. 2018 ; 1♂ 1♀, Heping, Dongmaoshan , ca 800 m, X. 10. 2013, reared from A. aspera , XII. 9/15. 2013, 13K7 (Y. F. Hsu) ; 1♂, Heping, Guguan , ca 800 m, XI. 24. 2017, reared from A. aspera , emgd. XII. 30. 2017, HSU 17 L15 (Y. F. Hsu); NANTOU Co ., 1♂, Renai, Huisun Forest Field, X. 15. 2012, reared from A. aspera , emgd. XII. 11. 2012, HSU 12 K14 (Y. F, Hsu); 1♂, Renai, Aowanda , VIII. 17. 2014, reared from A. aspera , emgd. XII. 11. 2012, HSU 14 H29 (W. J. Lin & J. R. Chen).

Figures

FIGS. 7–12. Ovum and larvae of Neptis reducta. 7. Ovum, lateral view. 8. 1st instar. 9. 2nd instar. 10. 3rd instar. 11. 4th instar. 12. 5th (final) instar.

FIGS. 13–18. Pupae of Neptis species associated with Aphananthe aspera. 13–14. N. reducta; 15–16. N. nata; 17–18. N. sappho.

FIGS. 19–23. Head capsules of Neptis reducta larvae. 19. 1st instar. 20. 2nd instar. 21. 3rd instar. 22. 4th instar. 23. 5th (final) instar. Scale bar = 200 μm for 19–20, 500 μm for 11–23.

FIGS. 24–28. Head capsules of Neptis nata larvae. 24. 1st instar. 25. 2nd instar. 26. 3rd instar. 27. 4th instar. 28. 5th (final) instar. Scale bar = 200 μm for 14–25, 500 μm for 26–28.

FIGS. 29–33. Head capsules of Neptis sappho larvae. 29. 1st instar. 30. 2nd instar. 31. 3rd instar. 32. 4th instar. 33. 5th (final) instar. Scale bar = 200 μm for 29–30, 500 μm for 31–33.