Megaloptera

Megaloptera contains alderflies, dobsonflies and fishflies. There are two living families: Sialidae and Corydalidae. Both families have aquatic larvae with terrestrial eggs, pupae and adults.

Sialidae (alderflies) is sparse in oriental, there are only seven species recorded. Sialis is the dominant genus which are mainly found in temperate regions such as Korea and Japan, and Sialis navasi was described from China in 2009. In Hong Kong, there is one endemic Indosialis mentioned in Handbook of Zoology edited by New, T. & Theischinger, G., but not much detail information is available.

Corydalidae (dobsonflies and fishflies) is widely distributed in holarctic and neotropic. There are eleven species recorded in Indochina including Neochauliodes boweringi that is widespread in Hong Kong. Corydalid larvae are predacious with well-developed mandibles by which capture a variety of aquatic invertebrates. Lateral abdominal filaments faciliate respiratory function and presence of abdominal spiracles enhance their survival in streams which dry out periodically. A pair of anal prolegs each bearing two terminal hooks is a key characteristics to distinguish it from other taxa group such as hydrophilid larvae.

 

References:

X. Y. Liu & D. Yang (2006) Revision of the genus Sialis from Oriental China (Megaloptera: Sialidae) Zootaxa 1108: 23-35