MICROHABITAT SEGREGATION IN TWO CLOSELY RELATED PIERID BUTTERFILES

Abstract

Pieris rapae crucivora and P. napi nesis live in the same area and feed on the same plant in Sapporo, northern Japan. The sympatric relation of these two species was reconsidered spatiotemporally at the immature and adult stages. Though no segregation pattern was found at the adult stage, vertical segregation at the immature stage between the two species was found on a common food plant, Rorippa sylvestris. Origin of the vertcial segregation as being limited to the immature stage is discussed preliminarily.