Protozoa - Nassellaria - Parvicingulidae

Named by Carter.

Original description: Test elongate, quite pointed apically, usually with ten to twelve post-abdominal chambers. Cephalis conical, possibly including a short apical horn. Remaining chambers in apical half of the test trapezoidal, increasing more in height than width as added; next few chambers cylindrical, final two chambers slightly constricted. Slightly raised circumferential ridges visible between postabdominal chambers on the distal portion of the test. Costae fine, narrowly spaced throughout length of test. Pores subcircular to subelliptical in shape.

Original remarks: Elodium mackenziei n. sp. differs from Elodium nadenense Carter (1988) in having less prominent circumferential ridges between post abdominal chambers and an absent to poorly developed apical horn. It differs from E. wilsonense Carter (1988) in having a more narrowly conical shape and less differentiated apical horn. Genus Elodium is queried because the three rows of aligned pores between chambers that characterize the genus are not well developed. E. mackenziei n. sp. may be ancestral to all other species of Elodium in the upper Toarcian and Aalenian of Queen Charlotte Islands and it may also represent the link between Parahsuum and Elodium.

Etymology: This species is named for J.D. MacKenzie (Geological Survey of Canada) who first mapped central Graham Island in 1913-1914.

Full reference: S. Gorican, E. S. Carter, P. Dumitrica, P. A. Whalen, R. S. Hori, P. De Wever, L. O'Dogherty, A. Matsuoka, and J. Guex. 2006. Catalogue and systematics of Pliensbachian, Toarcian and Aalenian radiolarian genera and species 446

Belongs to Elodium according to S. Gorican et al. 2006

Sister taxon: Elodium wilsonense

Type specimen: GSC 80758 (Carter et al1988, pl. 13, figs. 5, 10, 12).

Ecology: passively mobile planktonic omnivore

Distribution:

Show more details

Specimen images are retrieved through the ePANDDA API.