AMBULYX SIAMENSIS Inoue, 1991

TAXONOMY

Ambulyx siamensis Inoue, 1991, Tinea 13(14): 130. Type locality: Thailand, [Chaiyaphum,] Nam Proam, 800m.

ADULT DESCRIPTION AND VARIATION

Male similar to Ambulyx substrigilis but forewing upperside pattern paler and more indistinct, subbasal spot much smaller than in Ambulyx substrigilis or even absent, subterminal line narrow in blackish, slightly arched and fading just before reaching the tornus, no spot in the submarginal area between veins CuA1 and CuA2; underside subterminal line indistinct, brownish. Hindwing patterns heavier than in Ambulyx substrigilis with more scattered black scales (Jiang, Kitching, Xu, Xu, Yan, Yu, Liu & Hu, 2025).

In the male genitalia, uncus and gnathos similar to Ambulyx substrigilis. Sacculus slender, dorsal margin with a large, sharply pointed and curved, triangular hook, harpe narrowed to a blunt finger-like lobe. Phallus slender and curved, posterior lobe sharply pointed apically and with tiny teeth laterally.

ADULT BIOLOGY

Little known.

FLIGHT-TIME

China: 17.iv (Yunnan); vii (Yunnan); 6-29.viii (Yunnan).

EARLY STAGES

OVUM: Unknown.

LARVA:

Photos: Larvae of Ambulyx species from China. (A) Ambulyx moorei, Foshan, Guangdong, China; (B) Ambulyx sericeipennis sericeipennis, Hongkong, China; (C) Ambulyx ochracea, Guangzhou, Guangdong, China; (D) Ambulyx kuangtungensis, Guangzhou, Guangdong, China; (E) Ambulyx semiplacida montana, Pingbian County, Yunnan, China; (F) Ambulyx schauffelbergeri, Chongqing City, China; (G) Ambulyx siamensis, Mengla County, Yunnan, China; (H) Ambulyx siamensis, Mengla County, Yunnan, China; (I) Ambulyx liturata, Mt. Maoershan, Guangxi, China; (J) Ambulyx tobii, Kunming, Yunnan, China. (© Jiang, Kitching, Xu, Xu, Yan, Yu, Liu & Hu, 2025)

PUPA: Unknown.

Larval hostplants. From Parashorea chinensis in China, but in Thailand recorded from Shorea obtusa (Eitschberger & Ihle, 2010).

PARASITOIDS

Unknown.

LOCAL DISTRIBUTION

China: Yunnan (Xima, Yingjiang County, 1500m; Mengla Couny; Menglun, Xishuangbanna; Nabanhe Nature Reserve, Xishuangbanna, 1093m; Bulangshan, Menghai County, 1450m).

GLOBAL DISTRIBUTION

Southwestern China (Yunnan) and Thailand, Laos and Vietnam.

Map: Distribution of assorted species of Ambulyx from China: Ambulyx substrigilis (purple dotted line); Ambulyx siamensis (ochre squares); Ambulyx liturata (blue dotted line); Ambulyx moorei (red dotted line); Ambulyx canescens (green dotted line); Ambulyx ochracea (yellow patch); Ambulyx maculifera (black triangles); and Ambulyx zhejiangensis (pink triangles). (© Jiang, Kitching, Xu, Xu, Yan, Yu, Liu & Hu, 2025).

BIOGEOGRAPHICAL AFFILIATION