''Calodiscus'' is a genus of Eodiscinid

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...

in the family

Calodiscidae The Calodiscidae Kobayashi, 1943 'nom. transl.'' Öpik, 1975 ''ex'' Calodiscinae Kobayashi, 1943are a family of trilobites belonging to the order Agnostida that lived during the Lower Cambrian (Botomian and Toyonian). They are small or very smal ...

. It lived during the late Lower Cambrian, with remains found in Canada (Newfoundland & Labrador), the United States (Massachusetts, New York State), Greenland, The United Kingdom (England), Sweden, France, Germany, Italy (Sardinia), Kazakhstan, the Russian Federation and China. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

by original designation is ''Agnostus lobatus'' Hall, 1847 from the upper part of the lower Cambrian Browns Pond Formation (formerly Schodack Formation) at Troy in the Taconic region of New York State, USA ''Calodiscus korolevi'' Pokrovskaya ''in'' Ergaliev and Pokrovskaya, 1977; ''Calodiscus lakei'' Rasetti, 1952; and ''Calodiscus'' n. sp. A of Geyer, 1988, according to Cederström ''et al''., 1988 Lochman (1956)LOCHMAN, C. 1956. Stratigraphy, paleontology, and paleogeography of the ''Elliptocephala asaphoides'' strata in Cambridge and Hoosick Quadrangles, New York. ''Bulletin of the Geological Society of America'', 67, 1331 – 1396. demonstrated that ''Calodiscus agnostoides'' (Kobayashi, 1943) represents late meraspid instars of ''C. lobatus'' (Cederström ''et al''., 1988, p. 500).

References

Agnostida genera Cambrian trilobites Cambrian trilobites of Europe Eodiscina {{Trilobite-stub Cambrian genus extinctions