Protozoa - Nassellaria - Hsuidae
Original description: Test small, subconical, with short horn. Cephalis and thorax sparsely perforated, covered with layer of microgranular silica. Abdomen and subsequent five to six post-abdominal chambers trapezoidal to rectangular in outline, comprised of an inner latticed layer of small tetragonal pore frames. Outer layer comprised of long, relatively massive costae extending longitudinally from abdomen to final post-abdominal chamber Early chambers increasing in width gradually, first or second post abdominal chamber increasing rapidly in width, subsequent chambers decreasing slightly in width as added.
Original remarks: Hsuum parvulum n. sp. differs from Hsuum gratum n. sp. by having a smaller test with a shorter horn and by lacking ridges on the apical portion of the test.
Etymology: Parvulus-a-um (Latin, adj.) very small.
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 Hsuum according to K. Y. Yeh 1987
Sister taxa: Hsuum acutum, Hsuum altile, Hsuum amabile, Hsuum arabicum, Hsuum arenaense, Hsuum belliatulum, Hsuum brevicostatum, Hsuum cuestaense, Hsuum feliformis, Hsuum gratum, Hsuum lucidum, Hsuum lupheri, Hsuum matsuokai, Hsuum maxwelli, Hsuum mclaughlini, Hsuum medium, Hsuum mirabundum, Hsuum modicum, Hsuum mulleri, Hsuum optimum, Hsuum parasolense, Hsuum plectocostatum, Hsuum robustum, Hsuum rosebudense, Hsuum rutogense, Hsuum tamanense
Type specimen: NMNS (000089). Its type locality is Suplee-Izee area, OR-600A, which is in a Toarcian marine tuff/limestone in the Hyde Formation of Oregon.
Ecology: passively mobile planktonic omnivore
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.