Читать книгу A Manual of Philippine Birds - Richard C. McGregor - Страница 282

 a1. No frontal shield nor lappet; primaries attenuated at their tips; center tail-feathers not elongated. Hydralector (p. 150)

 a2. With a leaf-like frontal lappet; primaries not produced; center tail-feathers greatly elongated. Hydrophasianus (p. 151)