''Callavia'' is an
extinct
Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
,
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of
trilobite
Trilobites (; meaning "three-lobed entities") are extinction, extinct marine arthropods that form the class (biology), class Trilobita. One of the earliest groups of arthropods to appear in the fossil record, trilobites were among the most succ ...
arthropod
Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...
s. ''C. broegeri'' lived during the late
Atdabanian
Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approxi ...
stage, which lasted from 530 to 524 million years ago during the early part of the
Cambrian Period
The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovici ...
in what are today Canada and the United States.
Taxonomy
The position of ''Callavia'' in relation to other Olenellina has shifted repeatedly over time. Initially it was assigned to the Holmiinae by
Pierre Hupé, and was later moved back and forth to the Callaviinae.
Lieberman, however, argues ''Callavia'' is a basal member of the Judomioidea.
[
]
Reassigned species
* ''C. brevioculata'' = '' Nevadella cartlandi''
* ''C. burri'' = '' Pleisionevadella burri''
* ''C. callavei'' = '' Callavalonia callavei''
* ''C. cartlandi'' = '' Nevadella cartlandi''
* ''C. cobboldi'' = '' Nevadella cartlandi''
* ''C. eucharis'' = '' Nevadella eucharis''
* ''C. hastata'' = '' Callavalonia callavei''
* ''C. lotzei'' = '' Sdzuyomia lotzei''
* ''C. perfecta'' = '' Nevadella perfecta''
Distribution
''C. broegeri'' is known from the Lower Cambrian of Newfoundland (Brigus Formation, Branchian Series, Conception Bay), Nova Scotia (between Docters Brook and Malignant Brook, northernmost Antigonish Highlands), Canada, and Massachusetts, USA ( Weymouth Formation, Pearl street, North Weymouth, Mill Cove, Norfolk County).
Ecology
''C. broegeri'' occurs together with lampshells ''Sunnaginia imbricata'' and ''Eccentrotheca kanesia'', and
the agnostid ''Serrodiscus bellimarginatus''.Paleobiology Database
/ref>
See also
*'' Nevadella''
References
{{Taxonbar, from=Q26183
Olenellina
Cambrian trilobites
Fossils of Canada
Fossils of the United States
Monotypic trilobite genera
Paleontology in Newfoundland and Labrador
Paleontology in Nova Scotia
Paleozoic life of Nova Scotia