Polycystinea - Spumellaria - Hagiastridae
Description: Test as with genus, medium to large in size; central area moderately large, cortical shell with extremely large tetragonal, pentagonal, or hexagonal pore frames without nodes at vertices. Rays
wide, medium in length, tapering with short massive triradiate spines. Each ray with six rows of widely spaced external beams visible laterally. Well-preserved specimens with short bars connecting two contiguous external beams and forming large rectangular pore frames above two rows of smaller polygonal pore frames.
Remarks: Tetratrabs izeensis,n. sp., is compared with T imlayi, n. sp., under the latter species.
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 Tetratrabs according to Yeh 1987
Sister taxa: Tetratrabs acutusspina, Tetratrabs bulbosa, Tetratrabs noricus, Tetratrabs radix, Tetratrabs robustusspina, Tetratrabs zealis
Type specimen: NMNS (000029). 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 Japan (6 collections), United States (3: Oregon)
Total: 9 collections each including a single occurrence
Specimen images are retrieved through the ePANDDA API.
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