taxonID	type	description	language	source
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	diagnosis	Diagnosis. The new species can be easily distinguished from all other congeners by the valva having a short fingerlike process at the dorsal base, and a long clavate process extending from the ventral base to the cucullus.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	description	Description. Adults (Figs. 1 – 2, 5, 7). Forewing length: 14 – 18 mm in males; 18 – 22 mm in females. Frons and vertex covered with dark orange hairs. Labial palpus orange. Antenna bipectinate, stronger in males than in females, pale orange. Thorax and abdomen white. Forewing and hindwing white, with brown hairs on termen in males. Forewing costa orange about distal 1 / 4. Wing venation light green, forewings with vein R 3, R 4 and R 5 stalked, R 5 and M 1 almost parallel, M 2 and M 3 originating from the lower angle of discal cell; hindwing with R s and M 1 stalked, M 2 present. Legs white, with orange hairs terminally; hindlegs with a pair of white tibial spurs. Male genitalia (Fig. 9). Uncus short, digitate, pointed apically. Valva broad, elongate, folded inward at dorsum, with a short fingerlike process at dorsal base, a long clavate process from ventral base extending to cucullus; cucullus concaved inward at ventral half, dentate and strongly sclerotized at outer edge of dorsal half. Aedeagus short, more sclerotized distally. Female genitalia (Fig. 11). Papillae anales strongly sclerotized, finger-shaped, curved medially. Apophyses anteriores short, apophyses posteriores reduced. Ostium V-shaped, sclerotized. Ductus relatively long, membranous. Bursa nearly elliptical, with numerous stripe-like wrinkles, signum large, densely covered with tiny thorns. Larvae (Figs. 12 – 18). First instar body length 3 mm; yellow green dorsally, dark brown laterally; thoracic verrucae white; A 2, A 5 and A 9 with white verrucae. Second, third and fourth instars with black body coloration; thoracic verrucae orange in second instar, dark orange in third instar, black in fourth instar; abdominal verrucae white on A 2 and A 5 of instars 2 – 4, orange or black on A 9 of the third and fourth instars; A 3 – 5 with orange and black short brushes. Fifth instar body length 28 mm, ochre in ground color, with white stripes on thorax and abdomen; cephalic capsule black, clypeus white, labial, and antenna orange; each segment with a pair of orange lateral verrucae; brushes of A 3 – 5 and A 9 orange, but mixed with black color; middorsal gland white in all instars. Pupae (Fig. 19). Green, with a small yellow dot near spiracle on A 2 – A 5.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	biology_ecology	Host-plant. Castanopsis fissa. (Champ. ex Benth.) Rehd. et Wils. (Fagaceae).	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	materials_examined	Type material. Holotype: ♂, Fenghuangshan Provincial Nature Reserve, Chaozhou, Guangdong, China, 23 º 53 ’ 3.5376 ” N, 116 º 35 ’ 46.896 ” E, altitude 600 m, 1 - V- 2024, leg. Ziqi Yuan. Paratypes: 4 ♂, 2 ♀, same collecting data as holotype.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	distribution	Distribution. China (Guangdong).	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B237FF14BDC4B86CFA9C.taxon	etymology	Etymology. The new species is named after Lingnan, an area to the south of Wu Ling mountains in China.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	diagnosis	Diagnosis. The new species is similar to the above new species in external morphology, but can be separated from the latter by the forewing having a black dot in the discal cell, male genitalia with a bilobate uncus, and a sickle-shaped process originating from the dorsal base of the valva.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	description	Description. Male adults (Figs. 3 – 4, 6, 8). Forewing length 13 – 14 mm. Frons and vertcx covered with orange hairs. Labial palpus red. Antenna bipectinate, pale orange. Thorax and abdomen white. Forewing and hindwing both white, with brown hairs on termen. Forewing costa orange about distal 1 / 4, with a black dot in discal cell. Wing venation light green, forewings with vein R 3, R 4 and R 5 stalked, M 1 arising from near the upper angle of discal cell, M 2 originating from near the lower angle of discal cell; hindwing with Rs and M 1 arising from the upper angle of discal cell, M 2 present. Legs white, with orange hairs terminally, forelegs less; hindlegs with a pair of white tibial spurs. Male genitalia (Fig. 10). Uncus bilobate, well sclerotised apically. Valva lightly sclerotised, approximately rectangle, upper left corner slightly pointed, with a sickle-shaped process originating from dorsal base. Juxta weakly sclerotised. Aedeagus short, with a forked sclerotization terminally. Larvae (Figs. 20 – 27). First instar body length 2. 8 mm, dorsal side dark green, with white blotches; second instar dark green dorsally, throacic verrucae with orange bristles; third, fourth and fifth instars with two black dots and a cluster of brown bristles on a white blotch at the dorsal side between A 3 and A 4; fourth and fifth instars with two black longitudianl stripes on the dorsalateral side of body; head orange in the first three instars, black in the final two instars; forns with a yellow inverted V-shaped stripes along ecdysial suture; middorsal gland small and transparent in all instars.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	biology_ecology	Host-plant. (Fig. 28): Castanopsis fissa. (Champ. ex Benth.) Rehd. et Wils. (Fagaceae)	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	materials_examined	Type material. Holotype: ♂, Fenghuangshan Provincial Nature Reserve, Chaozhou, Guangdong, China, 23 º 53 ’ 3.5376 ” N, 116 º 35 ’ 46.896 ” E, altitude 600 m, 9 - V- 2024, leg. Ziqi Yuan. Paratypes: 3 ♂, 1 ♀, same collecting data as holotype.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	distribution	Distribution. China (Guangdong).	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	etymology	Etymology. The new species is named after the sickle-shaped protrusions on both sides of the valva in the male genitalia.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
03CB4B7E3053B230FF14B898BE6DF878.taxon	discussion	Remarks. Female adults of this new species are not described in the present paper for the following reasons: the only female adult specimen collected from field has been severely damaged after laying eggs during transportation, and no female adults have been successfully reared with its eggs.	en	Yuan, Ziqi, Ye, Peizhao, Huang, Weichao, Wang, Houshuai (2025): Two new species of the genus Arctornis Germar (Lepidoptera: Erebidae: Lymantriinae) from China. Zootaxa 5609 (3): 437-444, DOI: 10.11646/zootaxa.5609.3.9, URL: https://doi.org/10.11646/zootaxa.5609.3.9
