''Nosferatu'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

cichlid Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses ( Labridae), in the order Perciformes, but molecular studies have contradicted this ...

fishes endemic to the

Rio Panuco Rio or Río is the Portuguese, Spanish, Italian, and Maltese word for "river". When spoken on its own, the word often means Rio de Janeiro, a major city in Brazil. Rio or Río may also refer to: Geography Brazil * Rio de Janeiro * Rio do Sul, a ...

Basin and the tributaries of the adjacent Tamiahua Lagoon (to the South) and San Andrés Lagoon (to the North) in the states of

Veracruz Veracruz (), formally Veracruz de Ignacio de la Llave (), officially the Free and Sovereign State of Veracruz de Ignacio de la Llave ( es, Estado Libre y Soberano de Veracruz de Ignacio de la Llave), is one of the 31 states which, along with Me ...

Hidalgo Hidalgo may refer to: People * Hidalgo (nobility), members of the Spanish nobility * Hidalgo (surname) Places Mexico * Hidalgo (state), in central Mexico * Hidalgo, Coahuila, a town in the north Mexican state of Coahuila * Hidalgo, Nuevo Le� ...

San Luis Potosí San Luis Potosí (), officially the Free and Sovereign State of San Luis Potosí ( es, Estado Libre y Soberano de San Luis Potosí), is one of the 32 states which compose the Federal Entities of Mexico. It is divided in 58 municipalities and i ...

Tamaulipas Tamaulipas (), officially the Free and Sovereign State of Tamaulipas ( es, Estado Libre y Soberano de Tamaulipas), is a state in the northeast region of Mexico; one of the 31 states which, along with Mexico City, comprise the 32 Federal Entiti ...

and

Querétaro Querétaro (), officially the Free and Sovereign State of Querétaro ( es, Estado Libre y Soberano de Querétaro, links=no; Otomi language, Otomi: ''Hyodi Ndämxei''), is one of the Political divisions of Mexico, 32 federal entities of Mexico. I ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. The genus is characterized by a prolongation in the size of the symphysial pair of teeth relative to that of the other teeth in the outer row of the upper jaw (nosferatuform teeth); breeding pigmentation that consists of darkening of ventral area extending over nostrils, opercular series, and pectoral fins; depressed

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

rarely expands beyond anterior third of

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

; and an elongated, elastic, smooth

caecum The cecum or caecum is a pouch within the peritoneum that is considered to be the beginning of the large intestine. It is typically located on the right side of the body (the same side of the body as the appendix, to which it is joined). The w ...

adhered to a saccular stomach. All species in ''Nosferatu'' had previously belonged to its sister genus ''

Herichthys ''Herichthys'' is a small genus of cichlid fishes. Most are endemic to Mexico, but '' H. cyanoguttatus'' is also found in southern Texas (United States), and has been introduced to central Texas and Florida. In 2015, the genus was split, and 7 ...

''.

Species

There are currently 7 recognized species in this genus: * '' Nosferatu bartoni'' ( T. H. Bean, 1892) (Barton's cichlid) * ''

Nosferatu labridens ''Nosferatu labridens'', the curve-bar cichlid, is a species of cichlid freshwater fish endemic to the Laguna Media Luna and headwaters of the Río Verde between above sea level in the state of San Luis Potosí, Mexico. Its range is a part of t ...

'' ( Pellegrin, 1903) (Curve-bar cichlid) * ''

Nosferatu molango ''Nosferatu molango'' (previously placed in the genus ''Herichthys''), also known as Atezca Cichlid, is a species of cichlid endemic to the " Laguna Atezca", in the headwaters of the Rio Moctezuma (Rio Panuco Basin), in the municipality of Molang ...

'' ( De la Maza-Benignos & Lozano-Vilano, 2013) (Aztec cichlid) * ''

Nosferatu pame ''Nosferatu pame'', previously placed in the genus ''Herichthys ''Herichthys'' is a small genus of cichlid fishes. Most are endemic to Mexico, but '' H. cyanoguttatus'' is also found in southern Texas (United States), and has been introduced ...

'' ( De la Maza-Benignos & Lozano-Vilano, 2013) * ''

Nosferatu pantostictus ''Nosferatu pantostictus'', the Chairel cichlid, is a species of cichlid native to the Panuco River drainage of Mexico's Atlantic coast where it is mostly found in moderately fast flowing rivers, slightly brackish, murky lakes and lagoons along ...

'' ( J. N. Taylor &

R. R. Miller Robert Rush Miller (April 23, 1916 – February 10, 2003) "was an important figure in American ichthyology and conservation from 1940 to the 1990s." He was born in Colorado Springs, earned his bachelor's degree at University of California, Berke ...

, 1983) (Chairel cichlid) * ''

Nosferatu pratinus ''Nosferatu pratinus'' (previously placed in the genus ''Herichthys''), also known as green labridens or mojarra caracolera verde in Spanish, is a species of cichlid "endemic to the Rio el Salto,in the Rio Pánuco Basin in Mexico. The river runs ...

'' ( De la Maza-Benignos & Lozano-Vilano, 2013) * ''

Nosferatu steindachneri ''Nosferatu steindachneri'', Steindachner's cichlid, is a species of cichlid endemic to Mexico where it is found in the Tamasopo, Gallinas and Ojo Frio Rivers of the Panuco River basin. It reaches a maximum size of SL. This species can also ...

'' ( D. S. Jordan & Snyder, 1899) (Steindachner's cichlid)

Phylogenetics

Separate analysis of the mitochondrial gene ''

Cox1 Cytochrome c oxidase I (COX1) also known as mitochondrially encoded cytochrome c oxidase I (MT-CO1) is a protein that in humans is encoded by the ''MT-CO1'' gene. In other eukaryotes, the gene is called ''COX1'', ''CO1'', or ''COI''. Cytochro ...

'' by León-Romero ''et al.'' and by De la Maza-Benignos, ''et al.'' confirmed the monophyly of the genus group, and revealed the existence of three clades within: The

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

bartoni

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

, conformed by

sympatric In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sh ...

''N. labridens'' and ''N. bartoni''; the

(in their study León-Romero ''et al.'' did not consider ''N. pame'' nor included ''N. pratinus'' and consequently report

monophyly In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic grou ...

) steindachneri

, conformed of the allopatric ''N. pratinus'', and sympatric ''N. pame'' and ''N. steindachneri''; and the

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

pantostictus

(in the study by León-Romero ''et al.'' some of the lineages of ''N. pantostictus'' are misidentified as ''N. labridens''; consequently they report

polyphyly A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

) composed of the nominal species ''N. pantostictus''. In comparison to ''Herichthys'', high levels of intrageneric

divergence In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the quantity of the vector field's source at each point. More technically, the divergence represents the volume density of the ...

and

structure A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ...

within ''Nosferatu'' were revealed.

Evolution

Divergence time for the split between ''Herichthys'' and ''Nosferatu'' has been estimated in ~5 Mya. During these times (i.e.

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 ...

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58endorheic An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes ...

shallow lakes, where ''Nosferatu'' evolved into the bartoni (~3 Mya), steindacheri (~2Mya) and pantostictus (~2 Mya) clades. Later on (~1.8 Mya), as regional faulting rejoined the Rio Verde with the Pánuco Basin during the course of the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

, the genus re invaded the Pánuco, this time with the evolved mechanisms of reproductive isolation that allows its

sympatry In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sh ...

with ''

''.

Name

The name of this genus, ''Nosferatu'' was given because of the pair of well-developed recurved fangs in the upper jaw present possessed by all species of the genus, these were said to be reminiscent of those of the eponymous vampire in

F. W. Murnau Friedrich Wilhelm Murnau (born Friedrich Wilhelm Plumpe; December 28, 1888March 11, 1931) was a German film director, producer and screenwriter. He was greatly influenced by Schopenhauer, Nietzsche, Shakespeare and Ibsen plays he had seen at t ...

’s ''

Nosferatu ''Nosferatu: A Symphony of Horror'' (German: ''Nosferatu – Eine Symphonie des Grauens'') is a 1922 silent German Expressionist horror film directed by F. W. Murnau and starring Max Schreck as Count Orlok, a vampire who preys on the wife ...

''.

References

{{Taxonbar, from=Q16797260 Heroini Endemic fish of Mexico Freshwater fish of Mexico Freshwater fish genera Cichlid genera Taxa named by Mauricio De la Maza-Benignos Taxa named by María de Lourdes Lozano-Vilano Nosferatu