UNIKARYON MONTANUM SP. N. (PROTISTA, MICROSPORA), A NEW PATHOGEN OF THE SPRUCE BARK BEETLE, IPS-TYPOGRAPHUS (COLEOPTERA, SCOLYTIDAE)

Unikaryon montanum,sp. n. infects the fat body, muscle, Malpighian tub ules and ovaries of adult Ips trypographus L. The development is haplo karyotic, with separate nuclei during the schizogony and sporogony. Sp oronts have the cellular envelope with added layer of electron dense m aterial. Two types of spores are formed: small broad-oval primary spor es, 1.5 x 1.0 I-lm, with warty surface of spore wall, uninucleate, wit h isofilar polar filament in 5/6 coils and elongated-oval environmenta l spores, 0.8-1 x 2 mu m, with warty spore wall attenuated at the ante rior end, uninucleate, with spore polar filament in 8 coils. Both type s have a dual polaroplast with the anterior part of a layer of conflue nt fine lamellae ending posteriorly in bulbous processes, and posterio r part composed of coil of tubules.