Systematics and biogeography of the fishfly genus Parachauliodes (Megaloptera : Corydalidae) endemic to the east Asian islands

摘要

The fishfly genus Parachauliodes van der Weele, 1909 comprises six species from Taiwan, Japan, and South Korea, ranging along the east Asian islands. Herein, all the Parachauliodes species are described, including two new species, namely P. asahinai sp.n. and P. niger sp.n. A cladistic analysis based on adult and larval morphological characters was conducted to reconstruct the interspecific phylogeny of the Parachauliodes species. Two main clades within Parachauliodes were obtained from the cladistic analysis, namely 'P. asahinai + P. continentalis' and '(P. japonicus + P. yanbaru) + (P. nebulosus + P. niger)'. Based on the present interspecific phylogeny and distribution patterns of Parachauliodes, its ancestor might have invaded the east Asian islands by a land bridge from Taiwan via Ryukyu to the Japanese archipelago about 10-5 million years ago.