In the present study we describe a Nosema infection in a Phyllotreta nigripens population. The parasite was identified as Nosema phyllotretae. The spores are oval, 3.97 +/- 0.47 mu m (2.85-4.75) in length and 2.19 +/- 0.36 mu m (1.90-2.85) in width. The polar filament has commonly 14 coils. The spore wall is 138-200 nm thick and made up of a clear endospore (88-140 nm) and a uniform exospore (40-70 nm). The polar filament measures 100-125 nm in diameter in the mature spirals. The polaroplast is thin lamellar. This study presents P. nigripens as a new host for N. phyllotretae and a second infection locality in Turkey.