Morphology and chaetotaxy of the immature stages of the scorpionfly Panorpa liui Hua (Mecoptera: Panorpidae) with notes on its biology

The immature stages of the scorpionfly Panorpa liui Hua were obtained through rearing. The egg, larva and pupa were observed using light and scanning electron microscopy with special reference to the chaetotaxy of the first instar larva and pupa. The larva is of the eruciform type, with three pairs of thoracic legs and eight pairs of abdominal prolegs. The head of the larva bears a pair of compound eyes, each of which consists of 26 ommatidia. A fleshy tibial lobe is borne distally on the mesal side of the tibia of the thoracic legs. The telson bears a protrusile sucker of four anal forks. The pupa is exarate and decticous with sexual dimorphism in chaetotaxy and caudal segments. This species completes two generations per year, overwintering as the prepupal stage in the soil. The durations of egg, larva and pupa are 3-4, 13-19 and 8-10 days, respectively.