Actinocephalus carrilynnae N. Sp. (Apicomplexa: Eugregarinorida) from the Blue Damselfly, Enallagma civile (Hagen)

ABSTRACT. Actinocephalus carrilynnae , a new species of actinocephalid gregarine, is described from the blue damselfly, Enallagma civile . Trophozoites are unpaired, lying between the host's gut epithelium and peritrophic membrane, and attain a maximum length of at least 1,700 μ m. Protomerites are subspherical. Epimerites are globular, hemispherical with stub-shaped or truncated cone-shaped projections and are attached to the protomerite by means of a fluted stalk. Protomerite-deutomerite length ratio is 0.12 and relatively constant regardless of trophozoite length. Gametocysts are subspherical, 270–280 μ m in diameter, and undergo sporogenesis in 24–36 h, dehiscing by rupture. Spores are biconical, slightly crescent-shaped, and very uniform in size: 15 μ m long and 4–5 μ m wide. The parasite infects both adult and naiad hosts.