Protozoa - Nassellaria - Bagotidae
Original description: Test spindle-shaped (conical when broken), with five to seven post-abdominal chambers. Cephalis small, hemispherical without horn. Chambers increasing gradually in length, rapidly in width as added. Final post-abdominal chamber terminating in narrow tubular extension. Test wall double-layered. Inner latticed wall consisting of regularly aligned square to rectangular pore frames. Outer layer of cephalis imperforate, covered with layer of microgranular silica. Thorax and subsequent chambers with massive costae and thin transverse bars forming rectangular pore frames overlapping on inner layer. Bars of outer layer fragile, often broken and leaving short remnants at costae. About eleven to thirteen costae visible laterally. Pore frames gradually increasing in size from thorax to final post-abdominal chamber then decreasing in size distally.
Original remarks: Broctus ruesti n. sp., di&64256;ers from B. sp. A by having a narrower test with regular rectangular pore frames throughout the test rather than irregular pore frames on earlier chambers and regular pore frames on &64257;nal post-abdominal chambers.
Further remarks: Broctus ruesti Yeh is similar to Broctus selwynensis Pessagno & Whalen in general shape of the test and linear arrangement of pores. These two species differ in the shape of the first segments: B. ruesti is pointed apically whereas B. selwynensis is rounded.
Etymology: This species is named for Dr. D. Ruest, in honor of his contribution to the study of Radiolaria.
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 Broctus according to K. Y. Yeh 1987
Sister taxa: Broctus kuensis, Broctus selwynensis
Type specimen: NMNS (000065). Its type locality is Suplee-Izee area, OR-536J, which is in a Pliensbachian marine mudstone/limestone in the Nicely Formation of Oregon.
Ecology: passively mobile planktonic omnivore
Distribution:
• Jurassic of Canada (14: British Columbia collections), Japan (1), United States (3: Oregon)
Total: 18 collections each including a single occurrence
Specimen images are retrieved through the ePANDDA API.
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