Male body length 8-9 mm; antennae unipectinate, with very long branches. Light organ inconspicuous. Female 17-20mm long, wingless, light organ indistinct. Each tergite of larva largely covered by black mark, with red mark in the middle and lateral sides. A pair of light organ located at the 7th abdominal segment.
Distribution
：Deep Water Bay (HK Island), Lung Fu Shan, Tai Po Kau, Tsuen Kam Au, Ng Tung Chai, Wong Cheuk Yeung (Sai Kung)
, Ho Chung.
Adult flight period
：
Late October to late January
Other information
：Ocassionally, a pair of very dim light spots are visible from the ventral side of male abdomen. Whole body of the female glows weakly
, and in rare cases, a pair of much brighter light spots are visible from the 7th abdominal segment. Larvae feed on earthworms.
雄 Male 雄 Male 雄 Male 雄 Male 雌 Female (下 below) 雄 Male (上 above) 雌 Female 雌 Female 雌 Female 雌 Female 成熟幼蟲 Mature larva 初齡幼蟲 Early instar larva 幼蟲捕食蚯蚓 Larva feeding on earthworm
