Original description: Test as with genus, small, subcylindrical, with six to seven post abdominal chambers. Cephalis conical without horn. Thorax and subsequent chambers trapezoidal or rectangular in out line, increasing slightly in width as added. Earlier chambers sparsely perforate, covered with layer of microgranular silica. Post-abdominal chambers with thin to medium costae. About eight to ten costae visible laterally.
Etymology: Bellus-a-um (Latin, adj.) lovely.
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
Sister taxa: Parahsuum carpathicum, Parahsuum edenshawi, Parahsuum formosum, Parahsuum hiconocosta, Parahsuum izeense, Parahsuum longiconicum, Parahsuum mostleri, Parahsuum officerense, Parahsuum ovale, Parahsuum primitivum, Parahsuum publicum, Parahsuum simplum, Parahsuum vizcainoense, Lupherium nitidum, Lupherium snowshoense, Drulanta pulchra, Fantus exiguus, Fantus schoolhousensis
Type specimen: NMNS (000101). Its type locality is Suplee-Izee area, OR-589D, which is in a Toarcian marine mudstone/limestone in the Snowshoe Formation of Oregon.
Ecology: passively mobile planktonic omnivore