Polycystinea - Nassellaria - Tripedurnulidae
Original description: Test medium sized, subspherical, with nearly uniformly sized of pentagonal and hexagonal pore frames. Pore frames with thick rims and sides without prominent nodes at vertices. Apical horn about four times as long as vertical horn. Foot about as four fifths length of apical horn. Apical horn andfoot massive, triradiate in cross-section, with three narrow ridges alternating with three wide grooves, grooves nearly twice as wide as ridges. Vertical horn much shorter and thinner, triradiate with three narrow ridges alternating with three narrow grooves.
Etymology: Fidus-a-um (Latin, adj.) faithful.
Full reference: K. Y. Yeh. 1987. Taxonomic Studies of Lower Jurassic Radiolaria from East-Central Oregon. National Museum of Natural Science Special Publications 2:1-169
Belongs to Turanta according to K. Y. Yeh 1987
Sister taxa: Turanta morinae, Turanta nodosa
Type specimen: NMNS (000163). Its type locality is Suplee-Izee area, OR-600A, which is in a Toarcian marine tuff/limestone in the Hyde Formation of Oregon.
Distribution:
• Jurassic of United States (3: Oregon collections)
Total: 3 collections each including a single occurrence
Specimen images are retrieved through the ePANDDA API.
Click image to enlarge. Click to access iDigBio record.