''Obama'' is a

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 ...

land planarian Geoplanidae is a family of flatworms known commonly as land planarians or land flatworms. These flatworms are mainly predators of other invertebrates, which they hunt, attack and capture using physical force and the adhesive and digestive proper ...

s from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. It contains several species adapted to human-disturbed environments, including the only invasive land planarian native to the

Neotropical realm The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...

, ''

Obama nungara Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. Ob ...

'', which has been accidentally introduced in

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Description

The genus ''Obama'' is characterized by having a leaf-shaped body. Most species are about long, but some may reach over . The hundreds of eyes distributed along the body are of two types: monolobulated, which are simple and circular, and trilobulated, which have three lobes. The copulatory apparatus of ''Obama'' has a protrusible penis occupying the entire male atrium or most of it. Morphologically the genus can be divided in two subgroups depending on the shape of the penis papilla, which may be symmetrical or asymmetrical. The group with an asymmetrical penis papilla includes 10 species (''O. anthropophilla'', ''O. carbayoi'', ''O. carrierei'', ''O. decidualis'', ''O. josefi'', ''O. ladislavii'', ''O. marmorata'', ''O. nungara'', ''O. otavioi'' and ''O. ruiva'') and seems to form a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

clade within ''Obama''. On the other hand, the group with a symmetrical penis papilla is

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

, indicating that this is the ancestral state within the genus.

Etymology

The name ''Obama'' is formed by a composition of the Tupi words ''oba'' (leaf) and ''ma'' (animal), being a reference to the body shape of species in this genus. Unlike '' Baracktrema obamai'', Tosanoides obama, and Etheostoma obama, it is not named after former US President

Barack Obama Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. O ...

and the similarity between the names is purely coincidental.

Species

There are 45 species assigned to the genus ''Obama'', making it the largest genus in the subfamily Geoplaninae: *'' Obama allandra'' Marques, Rossi, Valiati & Leal-Zanchet, 2018 *'' Obama anthropophila'' Amaral, Leal-Zanchet & Carbayo, 2015 *''Obama apeva'' (Froehlich, 1959) *'' Obama apiguara'' Oliveira, Almeida & Carbayo, 2020 *''Obama applanata'' ( Graff, 1899) *''Obama argus'' ( Graff, 1899) *''Obama assu'' (Froehlich, 1959) *'' Obama aureolineata'' Iturralde & Leal-Zanchet, 2021 *'' Obama autumna'' Iturralde & Leal-Zanchet, 2021 *''Obama baptistae'' (Leal-Zanchet & Oliveira, 2012) *''Obama braunsi'' ( Graff, 1899) *''Obama burmeisteri'' (Schultze & Müller, 1857) *'' Obama carbayoi'' (Oliveira & Leal-Zanchet, 2012) *''Obama carinata'' (Riester, 1938) *''Obama carrierei'' ( Graff, 1897) *''Obama catharina'' (Hyman, 1957) *'' Obama decidualis'' Amaral & Leal-Zanchet, 2015 *''Obama dictyonota'' (Riester, 1938) *''Obama divae'' (Marcus, 1951) *''Obama eudoxiae'' (Ogren & Kawakatsu, 1990) *''Obama eudoximariae'' (Ogren & Kawakatsu, 1990) *''Obama evelinae'' (Marcus, 1951) *''Obama ferussaci'' ( Graff, 1897) *'' Obama ficki'' (Amaral & Leal-Zanchet, 2012) *''Obama fryi'' ( Graff, 1899) *''Obama glieschi'' (Froehlich, 1959) *''Obama itatiayana'' (Schirch, 1929) *'' Obama josefi'' (Carbayo & Leal-Zanchet, 2001) *'' Obama ladislavii'' ( Graff, 1899) *'' Obama leticiae'' Iturralde & Leal-Zanchet, 2021 *''Obama livia'' (E. M. Froehlich, 1955) *'' Obama maculatentis'' Negrete, Gira & Brusa, 2019 *'' Obama maculipunctata'' Rossi, Amaral, Ribeiro, Cauduro, Fick, Valiati & Leal-Zanchet, 2015 *''Obama marmorata'' (Schultze & Müller, 1857) *''Obama metzi'' ( Graff, 1899) *''

'' Carbayo, Álvarez-Presas, Jones & Riutort, 2016 *''Obama otavioi'' Carbayo, 2016 *''Obama poca'' (Froehlich, 1958) *''Obama polyophthalma'' ( Graff, 1899) *''Obama riesteri'' (Froehlich, 1955) *''Obama rufiventris'' (Schultze & Müller, 1857) *''Obama ruiva'' (E. M. Froehlich, 1972) *''Obama schubarti'' (Froehlich, 1958) *'' Obama tribalis'' Marques, Rossi, Valiati & Leal-Zanchet, 2018 *''Obama trigueira'' (E. M. Froehlich, 1955)

Phylogeny

The genus ''Obama'' was erected after a study of

molecular phylogeny Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

with the subfamily Geoplaninae revealed that the genus ''

Geoplana ''Geoplana'' is a genus of land planarians from South America. Taxonomic history The genus ''Geoplana'' was erected in 1857 by William Stimpson and included most land planarians with several eyes distributed along the body.Stimpson, W. (1857). ...

'', originally containing more than a hundred species, was

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

. One of the monophyletic clades revealed by the study was separate from ''Geoplana'' as the new genus ''Obama''. All species within the new genus share a similar morphology, including the leaf-shaped body, the presence of a permanent penis papilla, ovovitelline ducts entering the female atrium dorsally and dorsal eyes of two types: mono- and trilobulated. The sister-group of ''Obama'' seems to be the genus '' Cratera'', which has a very similar appearance but lacks trilobulated eyes. The following phylogenetic tree shows the relationship of several species of ''Obama'' after several molecular studies:

References

{{Taxonbar, from=Q18355807 Geoplanidae Rhabditophora genera