Abstract
A new acephaline gregarine is described from the earthworms Pheretima californica and Pheretima elongata. The gregarine was either embedded in the pharyngeal glandular tissue or found free in the coelomic fluid around the pharyngeal region in front of the crop. Adult trophozoites measured 48-65 mu m in diameter and are mostly active with a wavy pellicle. Heterogeneity in the endoplasm of active trophozoites was observed. Gametocysts measured 56-81 mu m in diameter, with a characteristic thick cyst wall. Navicular sporocysts measured 5.8 +/- 0.2 x 3.5 +/- 0.4 mu m, with small truncate plugs.