Functional morphology of the larval mouthparts of Panorpodidae compared with Bittacidae and Panorpidae (Insecta: Mecoptera)

摘要

In Mecoptera, the larvae of Bittacidae and Panorpidae are saprophagous, but the feeding habit of larval Panorpodidae remains largely unknown. Here, we compare the ultramorphology of the mouthparts of the larvae among the hangingfly Bittacus planus Cheng, 1949, the scorpionfly Panorpa liui Hua, 1997, and the short-faced scorpionfly Panorpodes kuandianensis Zhong, Zhang & Hua, 2011 to infer the feeding habits of Panorpodidae. The molar region of Panorpodidae is glabrous, lacking the long spines for filtering (preventing larger particles from entering the pharynx) as found in Bittacidae or the tuberculate teeth for grinding as present in Panorpidae. The mandibles of Panorpodidae are unsuitable for grinding, and most likely, larval Panorpodidae have different feeding habits than larval Bittacidae and Panorpidae. The diversity of the larval feeding habits in Mecoptera and its evolutionary advantage are briefly discussed.