''Concavus'' is a genus of

barnacle A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in eros ...

Species

WoRMS Worms may refer to: *Worm, an invertebrate animal with a tube-like body and no limbs Places *Worms, Germany, a city **Worms (electoral district) *Worms, Nebraska, U.S. *Worms im Veltlintal, the German name for Bormio, Italy Arts and entertainme ...

recognizes the following two species: * ''

Concavus concavus ''Concavus'' is a genus of barnacles. Species , WoRMS recognizes the following two species: * '' Concavus concavus'' (Bronn, 1831) — Pliocene–early Pleistocene; Western Europe. * '' Concavus crassostricola'' Zullo, 1984 — Early Miocene; No ...

'' (Bronn, 1831) —

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58early Pleistocene The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...

; Western Europe. * ''

Concavus crassostricola ''Concavus'' is a genus of barnacles. Species , WoRMS recognizes the following two species: * ''Concavus concavus'' (Bronn, 1831) — Pliocene–early Pleistocene; Western Europe. * '' Concavus crassostricola'' Zullo, 1984 — Early Miocene; Nor ...

'' Zullo, 1984 —

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was prece ...

; North Carolina and northern Florida.

Taxonomic history

The genus was

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every polyg ...

by William A. Newman in 1982. His original list of subgenera and species for the genus was the following: * ''Concavus'' genus ** ''Concavus'' subgenus *** '' C. concavus'' ** ''Menesiniella'' subgenus *** ''C. (M.) aquila'' *** ''C. (M.) regalis'' ** ''Arossia'' subgenus *** ''C. (A.) panamensis'' **** ''C. (A.) p. panamensis'' **** ''C. (A.) p. eyerdami'' *** ''C. (A.) henryae'' Newman noted there were multiple fossil taxa in this genus, but didn't classify any except for the type species ''C. concavus''. In 1992, Victor A. Zullo revised the genus. He created a new subfamily, Concavinae, with '' Tamiosoma'' (the senior synonym of ''

Menesiniella ''Menesiniella'' is a genus of the barnacle family Balanidae The Balanidae comprise a family of barnacles of the order Balanomorpha. As a result of research published in 2021 by Chan et al., the members of the family Archaeobalanidae were merg ...

'' according to Zullo), ''

Arossia ''Arossia'' is a genus of barnacles belonging to the family Balanidae The Balanidae comprise a family of barnacles of the order Balanomorpha. As a result of research published in 2021 by Chan et al., the members of the family Archaeobalanidae ...

'' and ''Concavus'' among its genera. With his revision, ''Concavus'' only consists of the two species ''C. concavus'' and ''C. crassostricola''.

Fossil records

This genus is known in the

fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

s from the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

to the

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

(age range: from 28.4 to 0.012 million years ago). Fossils are found in the marine strata of United States, Italy, Mexico, Morocco, Algeria, France, Haiti, Madagascar, Panama, Colombia and Slovenia.Fossilworks
/ref>

Notes

References

Barnacles Aquitanian genus first appearances {{Maxillopoda-stub