A NEW SPECIES OF LOMA (MICROSPOREA) IN SHINER PERCH (CYMATOGASTER AGGREGATA)

Loma embiotocia n. sp. is described from the gills of shiner perch (Cy matogaster aggregata) from waters off Vancouver Island, British Columb ia, Canada. Highest prevalence at a site was 15% and greatest intensit y was 583 xenomas per fish. Xenomas averaged 0.13 mm in diameter (0.06 -0.16 mm) and contained ovoid spores 4.8 x 2.6 (4.0-5.0 x 2.0-3.0) mu m. Sporogonic stages were dispersed throughout the xenomas. The xenoma wall was smooth lacking invaginations into the cytoplasm; sporoblasts were not highly vacuolated, and the sporophorous vesicle formed befor e sporogony. In addition to differences in host and geographic locatio n the new species is distinguished from Loma salmonae, the only other species in the genus known from British Columbia, by its internal tran scribed spacer (ITS) ribosomal DNA sequence.