Polycystinea - Nassellaria - Hilarisiregidae
Original description: Test dicyrtid. Cephalis medium in size, hemispherical imperforate, covered with layer of microgranular silica. Two horns elongate, nearly equal in length, triradiate with three narrow grooves. Thorax inflated in distal portion, test wall comprised of relatively large polygonal pore frames with larger pore frames in central portion and smaller pore frames at both ends. Pore frames thin in rims and sides. Four feet thin, moderately long, originating from upper part of thorax, feet triradiate in axial section with three narrow ridges alternating with three narrow grooves. Aperture large, circular in outline, with velum-like structure when well-preserved.
Original remarks: Rolumbus beatus, n. sp., can be distinguished from R. mirus Pessagno, Whalen, and Yeh (1986) by having a test with less massive pore frames and horns.
Etymology: Beatus-a-um (Latin, adj.) happy.
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 Rolumbus according to K. Y. Yeh 1987
Sister taxa: Diceratigalea gastili, Diceratigalea halseyensis, Rolumbus hilarus, Rolumbus lautus
Type specimen: NMNS (000115). Its type locality is Suplee-Izee area, OR-589D, which is in a Toarcian marine mudstone/limestone in the Snowshoe 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.