Protozoa - Nassellaria - Syringocapsidae
Original description: Test multicyrtid, spindle-shaped (conical when broken), with or without constrictions between joints. Cephalis dome-shaped with horn. Earlier chambers covered with layer of microgranular silica, remaining chambers consisting of single layer of regular to subregular polygonal pore frames. Final post-abdominal chambers slightly inflated and terminating in open, narrow, elongate, tubular extension.
Original remarks: Pleesus, n. gen., differs from Katroma Pessagno and Poisson (1981) by lacking a horn on cephalis, and by having a less inflated final post-abdominal chamber.
Etymology: Pleesus is a name formed by and arbitrary combination of letters (ICZN, 1985, Appendix D, pt. VI, Recommndation 41, p. 201).
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
Parent taxon: Syringocapsidae according to K. Y. Yeh 1987
See also Sepkoski 2002
Sister taxa: Dibolachras, Dicolocapsa, Ducatus, Fultacapsa, Japonocapsinae, Katroma, Parapodocapsa, Podobursa, Podocapsa, Quarticella, Squinabollum, Syringocapsa, Teesium, Yamatoum
Subtaxa: Pleesus aptus
Ecology: passively mobile planktonic omnivore
Distribution:
• Jurassic of Canada (3: British Columbia collections), Japan (2), Mexico (1), Oman (2), the Philippines (3), United States (5: Oregon)
Total: 16 collections including 18 occurrences
Specimen images are retrieved through the ePANDDA API.
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