Black-and-white-casqued Hornbill (Bycanistes subcylindricus) [XC18188]
by Rory Nefdt from Kakamega Forest Reserve, Kenya (call)
Black-and-white-casqued Hornbill (Bycanistes subcylindricus) [XC452010]
by Andres Angulo from Zimmerman Plot, Kakamega Forest, Kenya (song)
Subspecies
Genus sometimes merged with Ceratogymna. Subspecies rather poorly differentiated.
The following 2 subspecies are recognised:
subcylindricus (Sclater, 1870) - Sierra Leone, north-eastern Liberia and Ivory Coast east to western Nigeria (delta of R Niger).
subquadratus Cabanis & Schutt, 1880 - Eastern Nigeria, Cameroon and Central African Republic east to southern Sudan, and south to northern and eastern Zaire, Uganda, south-western Kenya and north-western Tanzania. Also northern Angola.