sirenian
The Sirenia (), commonly referred to as sea-cows or sirenians, are an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. The Sirenia currently comprise two distinct f ...
dugong
The dugong (; ''Dugong dugon'') is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest m ...
that lived in warm shallow seas in what is now
Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
and
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 The species is listed in the
Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.
History
The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ...
, funded by the
Australian Research Council
The Australian Research Council (ARC) is the primary non-medical research funding agency of the Australian Government, distributing more than in grants each year. The Council was established by the ''Australian Research Council Act 2001'', ...
.
In their book, ''Ecology and Conservation of the Sirenia: Dugongs and Manatees'', authors Helena Marsh, Thomas J. O'Shea and John E. Reynolds III, describe the evolution of ''Nanosiren garciae'' from the ''
Crenatosiren
''Crenatosiren'' is an extinct genus of dugongid sirenian known from the late Oligocene (Chattian) of Florida, North Carolina, and South Carolina. The type and only known species is ''Crenatosiren olseni''.
Taxonomy
''Crenatosiren'' was original ...
'' lineage, and argue that their small size allowed them access to very shallow water unavailable to larger sea mammals.
Taxonomy
''Nanosiren garciae'' was named by Domning and Aguilera (2008). Its name was attributed to Domning, not Domning and Aguilera. It was assigned to Dugonginae by Domning and Aguilera (2008).
Description
''Nanosiren garciae'', an extinct sirenian, was classified and named in 2008 based on fossils uncovered from the
Bone Valley
The Bone Valley is a region of central Florida, encompassing portions of present-day Hardee, Hillsborough, Manatee, and Polk counties, in which phosphate is mined for use in the production of agricultural fertilizer. Florida currently contains t ...
Formation near
Tampa, Florida
Tampa () is a city on the Gulf Coast of the United States, Gulf Coast of the U.S. state of Florida. The city's borders include the north shore of Tampa Bay and the east shore of Old Tampa Bay. Tampa is the largest city in the Tampa Bay area and ...
. It is the smallest known post-
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
sirenian, with body lengths of about 2 meters and weighing about 150 kg. Newborn nanosirens may have weighed only 6.8 kg. Its small size gave rise to the naming of its genus as ''Nanosiren'', from the Greek for a "dwarf siren". These mammals were of shallow draft and possessed small, conical tusks, suggesting they foraged in shallower waters than their dugong relatives. ''Nanosiren'' likely fed on smaller seagrasses near shorelines. They thrived approximately 5 million years ago during the
Hemphillian
The Hemphillian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 10,300,000 to 4,900,000 years BP. It is usually considered ...
age.
A map of locations where fossils of ''Nanosiren garciae'' has been created, ranging from Chile and Peru in South America to the United States, can be found at the
Global Biodiversity Information Facility
The Global Biodiversity Information Facility (GBIF) is an international organisation that focuses on making scientific data on biodiversity available via the Internet using web services. The data are provided by many institutions from around the ...
.
The species was described and named by Daryl P. Domning of Howard University and Orangel A. Aguilera of the Universidad Nacional Experimental Francisco de Miranda, Venezuela in 2008, along with a second plausible species ''Nanosiren sanchezi''. The name was chosen to commemorate famed Florida paleontologist Frank A. Garcia, who uncovered many fossil samples of the extinct mammal from the Bone Valley phosphate mines in Central Florida.