The terrestrial firefly Pyrocoelia pectoralis (E. Oliv., 1883) (Coleoptera: Lampyridae) was discovered in mainland China in 2002. The larvae of P. pectoralis inhabit moist grasslands and deserted farmlands rich in terrestrial vegetation. We recorded P. pectoralis mainly feeding on two species of land snails, Bradybaena similaris (Férussac) and Bradybaena ravida ravida (Benson) (Stylommatophora: Bradybaeniidae). A predator of adult fireflies was also recorded for the first time: the spider, Tetragnatha praedonia (L. Koch) (Araneae: Tetragnathidae). The prepupal stage of P. pectoralis lasted 5.3 (female) and 6.2 (male) days. The pupal stage lasted 8.4 (female) and 13.4 (male) days at 25°C. The imaginal period lasted from September to October. The photic emission of P. pectoralis was 526.5 ~ 593.9 nm, with the peak emitted wavelength (λ_max) at 548.6 nm. A female can mate with a male immediately after emergence and with several different males. The total number of eggs laid by mated females was correlated with the female's initial mass (y = 235.28x−20.38, R² = 0.7283, n = 44, P < 0.01). The average number of eggs laid was 72.0. In addition, unmated females can also lay eggs. Reflex bleeding was observed in the adults of these fireflies.