Calathium is an extinct genus of organism found in marine beds of Ordovician age. Its classification is enigmatic: It has long been placed among the receptaculites,[1][2] but it has also been described as a quasi-sponge,[3] possibly akin to the archeocyathids[4] or other hypercalcified sponge.[5] The chief difference from archaeocyathids is that their walls were connected by rods rather than septae.[4]
The organisms were important reef-forming organisms during the Ordovician, forming communities with lithistid sponges that gradually displaced the earlier microbial mounds.[4]
^Fisher, Daniel C.; Nitecki, Matthew H. (January 1982). "Standardization of the Anatomical Orientation of Receptaculitids". Journal of Paleontology. 56 (S13): 1–40. doi:10.1017/S0022336000061928.
^Church, Stephen B. (July 1991). "A new Lower Ordovician species of Calathium , and skeletal structure of western Utah calathids". Journal of Paleontology. 65 (4): 602–610. doi:10.1017/S0022336000030699.
^Toomey, Donald F.; Ingels, Jerome J. C. (1964). "Reported Silurian Occurrence of Calathium from the Thornton Reef, Illinois: A Correction". Journal of Paleontology. 38 (6): 1102–1104. JSTOR 1301646.
^ abcLi, Qijian; Li, Yue; Wang, Jianpo; Kiessling, Wolfgang (May 2015). "Early Ordovician lithistid sponge– Calathium reefs on the Yangtze Platform and their paleoceanographic implications". Palaeogeography, Palaeoclimatology, Palaeoecology. 425: 84–96. doi:10.1016/j.palaeo.2015.02.034.
^Meng, Miaomiao; Fan, Tailiang; Duncan, Ian (March 2021). "Sedimentary characteristics of the Lower to Middle Ordovician Calathium reefs in the northwestern Tarim Basin, NW China". Carbonates and Evaporites. 36 (1): 4. doi:10.1007/s13146-020-00665-7.
Calathium is an extinct genus of organism found in marine beds of Ordovician age. Its classification is enigmatic: It has long been placed among the receptaculites...
specialised, composite flower head or pseudanthium, technically called a calathium or capitulum, that may look superficially like a single flower. The capitulum...
Pausanias says that in the district of Gerenia there was a mountain called Calathium, upon which there was a sanctuary of Claea (an Oread), and close to the...
the McKelligon Member, built up of siliceous sponges and receptaculitid Calathium. The formation was first named by George Burr Richardson in 1904 for exposures...
†Cabrieroceras †Cabrieroceras crispiforme – or unidentified related form †Calathium †Calcispheara †Calcitornella †Calcivertella †Caliendrum – or unidentified...