Obama (genus)

Obama
Obama nungara
Scientific classification
Kingdom: Animalia
Phylum: Platyhelminthes
Class: Rhabditophora
Order: Tricladida
Suborder: Continenticola
Family: Geoplanidae
Subfamily: Geoplaninae
Genus: Obama
Carbayo et al., 2013
Type species
Geoplana fryi
Graff, 1899

Obama is a genus of land planarians from South America. It contains several species adapted to human-disturbed environments,[1] including the only invasive land planarian native to the Neotropical ecozone, Obama nungara, which has been accidentally introduced in Europe.[2]

Description

The genus Obama is characterized by having a leaf-shaped body. Most species are about 10 centimetres (3.9 in) long, but some may reach over 20 centimetres (7.9 in). The hundreds of eyes distributed along the body are of two types: monolobulated, which are simple and circular, and trilobulated, which have three lobes.[3]

The copulatory apparatus of Obama has a protrusible penis occupying the entire male atrium or most of it.[4] 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 clade within Obama.[5] On the other hand, the group with a symmetrical penis papilla is paraphyletic, indicating that this is the ancestral state within the genus.[5]

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.[3]

Species

There are 40 species assigned to the genus Obama:

Phylogeny

Three specimens of Obama of different species in a Petri dish. From top to bottom: O. ladislavii, O. anthropophila and O. nungara

The genus Obama was erected after a study of molecular phylogeny with the subfamily Geoplaninae revealed that the genus Geoplana, originally containing more than a hundred species, was polyphyletic.[3] 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.[3]

The sister-group of Obama seems to be the genus Cratera, which has a very similar appearance but lacks trilobulated eyes.[3][6]

The following phylogenetic tree shows the relationship of several species of Obama after several molecular studies:[2][3][5][6]

 

 

 

Obama baptistae

 
 

 

Obama braunsi

 
 

 

Obama apeva

 
 

Obama ficki

 
 
 
 
 

 

Obama fryi

 
 

 

 

Obama eudoximariae

 
 

 

Obama carinata

 
 

Obama itatiayana

 
 

 

Obama burmeisteri

 
 

Obama maculipunctata

 
 

 

Obama applanata

 
 

Obama argus sensu Graff, 1899

 
 
 
 
 
 

 

Obama argus sensu Schirch, 1929

 
 

 

Obama ladislavii

 
 

 

Obama nungara

 
 

Obama otavioi

 
 

 

Obama josefi

 
 

 

Obama marmorata

 
 

 

Obama anthropophila

 
 

Obama decidualis

 
 
 
 
 
 
 
 
 
 

References

  1. ↑ Boll, Piter Kehoma; Leal-Zanchet, Ana Maria (2016). "Preference for different prey allows the coexistence of several land planarians in areas of the Atlantic Forest". Zoology. 119: 162–168. doi:10.1016/j.zool.2016.04.002. ISSN 0944-2006.
  2. 1 2 3 Carbayo, Fernando; Álvarez-Presas, Marta; Jones, Hugh D.; Riutort, Marta (2016). "The true identity of Obama (Platyhelminthes: Geoplanidae) flatworm spreading across Europe". Zoological Journal of the Linnean Society. 177 (1): 5–28. doi:10.1111/zoj.12358. ISSN 0024-4082.
  3. 1 2 3 4 5 6 Carbayo, F.; Álvarez-Presas, M.; Olivares, C. U. T.; Marques, F. P. L.; Froehlich, E. X. M.; Riutort, M. (2013). "Molecular phylogeny of Geoplaninae (Platyhelminthes) challenges current classification: Proposal of taxonomic actions". Zoologica Scripta. 42 (5): 508–528. doi:10.1111/zsc.12019.
  4. 1 2 3 Marques, Alessandro; Rossi, Ilana; Valiati, Victor Hugo; Leal-Zanchet, Ana Maria (2018). "Integrative approach reveals two new species of Obama (Platyhelminthes: Tricladida) from the South-Brazilian Atlantic Forest". Zootaxa. 4455 (1): 99–126. doi:10.11646/zootaxa.4455.1.4. ISSN 1175-5334.
  5. 1 2 3 Carbayo, Fernando; Francoy, Tiago M.; Giribet, Gonzalo (2016). "Non-destructive imaging to describe a new species of Obama land planarian (Platyhelminthes, Tricladida)". Zoologica Scripta: n/a–n/a. doi:10.1111/zsc.12175. ISSN 0300-3256.
  6. 1 2 Rossi, Ilana; Amaral, Silvana Vargas; Ribeiro, Giovana Gamino; Cauduro, Guilherme Pinto; Fick, Israel; Valiati, Victor Hugo; Leal-Zanchet, Ana Maria (2015). "Two new Geoplaninae species (Platyhelminthes: Continenticola) from Southern Brazil based on an integrative taxonomic approach". Journal of Natural History. 50 (13–14): 787–815. doi:10.1080/00222933.2015.1084057. ISSN 0022-2933.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.