Abstract: The aquatic firefly Luciola substriata (Gorham) was newly found in the mainland of China. The external morphological studies showed adults were yellow in the whole except that the head and the end of elytra were black in ventral view. The light organs of adults were all cream white. Males had two luminescent organs, the first one at the 5th abdominal segment is rectangular in shape where as the second one at the 6th abdominal segment V-shaped. Females had only one luminescent organ in rectangular shape located at the fifth abdominal segment. Eggs were elliptic and yellow orange in color. There were two types of larva. The 1st－2nd instar larva had 7 pairs of branched tracheal gills located laterally on the 1st－7th abdominal segment. The 3rd-6th instar larva had no gills. Larva had a pair of spot-shaped light organs located at the 7th abdominal segment. The larval light organs regressed and were replaced by adult lantern in the pupal stage. Luciola substriata was normally found in ponds, lakes and rivers with flourish duckweeds and other aquatic vegetation. The firefly occurred one generation per year. The lastinstar larva climbed the strand and constructed earthen pupa cells, in which prepupal, pupal and preimaginal stages were spent till it matured in May next year. The prepupal stage lasted 6.17 days, and the pupal stage las td 4.43 days, in room temperature. The imaginal period lasted from May to mid September. The courtship flashing activity reached peak one hour after sunset. Eggs hatched after 12.5 days. Prey records included 2 species of aquatic snails, Lymnaea stagnalis and Gyraulus conwexiusculus. Three predators of this firef ly were recorded: red swamp crayfish (Procambarus clarkii), crab (Eriocheir sinensis) and grass carp (Ctenopharyngodon idellus). The light spectrum emitte d by Luciola substriata was measured as 425－603 nm with the peak 504 nm.

Key words: Aquatic firefly, Luciola substriata, morphology, biology, courtship flashing rhythm, light spectrum