Polycystinea - Nassellaria - Hilarisiregidae
Original description: Cephalis relatively small, dome-shaped, imperforate, covered with layer of microgranular silica. Two horns elongate, triradiate in axial section with three narrow ridges alternating with three narrow grooves. Thorax narrow proximally, wide distally; distal end about two to three times as wide as proximal end. Pore frames of thorax moderately massive, slightly variable in size. Four feet originating from cephalis, elongate, triradiate in axial section with three narrow ridges alternating with three wide grooves. Aperture large, subcircular in outline.
Original remarks: Rolumbus lautus, n. sp., can be distinguished from other Rolumbus spp. in this report by having extremely long horns and feet.
Etymology: Lautus-a-um (Latin, adj.) fine, elegant.
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 beatus
Type specimen: NMNS (000119). 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 (5: Oregon collections)
Total: 5 collections each including a single occurrence
Specimen images are retrieved through the ePANDDA API.
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