Revised description: Specimens with lattice and spine structure apparently identical with T. sicarius are comparatively common in the Ford Lake assemblage, though breakage frequently prevents determination of the full spine complement and symmetry. At least four specimens can reliably be allocated to Defiandre's species, though one is partly crushed. The spines of the species are highly distinctive, very broad at the base, fundamentally three-bladed but with each blade subdivided along the earlier part of its length, the spine terminating as a weakly three-bladed or unbladed rod. Edges of main and subsidiary blades are blunt, rounded, and, in at least some cases, swollen. Stratigraphic range:Early to Middle Tournaisian, Carboniferous, Paleozoic. Visean, France; Ford Lake Shale, Kandik Basin, Alaska.

Revised description:Specimens VA 2460 and UA 2461 have pore and spine structure apparently identical with T. sicarius s.s.; but, in UA 2461, one spine is distinctly weaker than the other three, and, in UA 2460, no trace of a fourth spine can be found, though orientations of the three spines present are similar to the orientations of any three spines in T. sicarius s.s. Remarks:It is not known whether such variants occur in the Cabrières type material, but they do occur associated with T. sicarius s.s. in the Baltalimani assemblage. Nineteen specimens with shell and spine structure similar to T. sicarius s.s. were examined in the Keele University collection. In one specimen (and perhaps a second) no trace of a fourth spine was found, and, in two specimens (and perhaps a third), the fourth spine is weaker than the other three. Thus, Ford Lake and Baltalimani populations appear to be similar, and it is reasonable to extend the definition of Triaenosphaera to include such populations with a minority of "abberrant" specimens. Stratigraphic range:Early to Middle Tournaisian, Carboniferous, Paleozoic. Visean, France; Ford Lake Shale, Kandik Basin, Alaska. Subsequent description:?

Literature cited:- Holdsworth, B. K., D. Jones, and Allison (1978). Upper Devonian radiolarians separated from chert of the Ford Lake Shale, Alaska. Journal of Research, United States Geological Survey 6(6): 775-788.