Body length 11-12 mm, vertex yellowish brown, some individuals have darker vertex; elytra bearing a prominent longitudinal ridge; light organs occupying ventrite 6 & 7 in male; only ventrite 6 in female. Female resembles male, but with smaller compound eyes.
Ng Tung Chai Valley, Sha Lo Tung, Lam Tsuen Valley, Lin Au.
Adult flight period
May to June.
：Often found in lowland abandoned farmland, sometimes thousands appear at the same time. Flying male displays flashes with about 100 ms duration and inter-flash intervals of 2.5 s, each flash is composed of 2 closely connected pulses