Subfamily Serrasalminae? or Family Serrasalmidae?

Subfamily Serrasalminae or Family Serrasalmidae?

Keeping up with the scientific changes

By Frank Magallanes, OPEFE

Photo (left) demonstrate different body forms of the pirambeba S. rhombeus (top) P. nattereri (bottom)

INTRODUCTION

The systemic of the Characiformes has long been (and continues to be) a difficult task to undertake. They were recognized as a homogeneous group in 1844 by German ichthyologist's Müller and Trochel. The Viennese Kner and his student Steindachner (between 1858-1915) followed by describing accurately a number of species without paying much attention to the classification. It was not until much later that Carl H. Eigenmann (considered to be the Father of Characoidologist) established the natural classifications of characins from South America. His principal manuscripts were posted between 1910 and 1927. He was then followed by one of his students Dr. George S. Myers. Within recent modern times a series of anatomical studies was completed by S. Weitzman, T. Roberts, and others helped establish the critical position of several groups, which led to the recognition of many families within the suborder (a recognition that would not have been accepted during Eigenmann's time). The research revealed the importance, as well as the complexity, of the Characiformes, and is presently considered as a key-group among teleosts. Included in this huge grouping to be discussed specifically at this website are the Serrasalmin which includes the pacus, silver dollars, pirambebas and of course, the true piranhas. The first authoritative division of the Characoids into several families (16) was done by S. Weitzman, in Greenwood et al. (1966). The French ichthyologist J. Géry (1972) would modify this order in a later manuscript.

Piranha and Pirambeba have distinctive body differences which become apparent as maturity sets in. These differences are the key reason why South American natives call non-true piranhas by other names. It is only outside South America (or S. A. non-fishing city dweller's) that the name "piranha" is loosely applied to all species within the subfamily Serrasalminae.

HISTORICAL IMAGES COURTESY OF ADRIEN LEROY

GENERAL EXPLANATION

The name Serrasalminae means saw-salmon-family the saw or serration pertaining to the scutes (or serrated keel) found on the belly of these fishes. Both carnivorous (single row teeth per jaw) and the vegetarian (double row teeth per jaw) practice mimicry. Perhaps this has much to do with the ecological home they inhabit and survival.

The epithet "piranha" is perhaps the most over used common name on fishes that could not even be scientifically called piranhas. It has been used for Serrasalminae vegetarian fishes and other related forms. In order to properly understand what a piranha is, one must do some research into common names and how they are applied. The Piranha Book, edited by Dr. G. S. Myers, (pg 26, TFH Publications Inc.,1971) covers what the usage of common names should be defined as. I recommend the research student use that reference to understand common name usage.

I frequently use the loose term piranha when I am discussing the "carnivorous" group as a whole, since this is the name more closely associated with the fish. For specifics, I prefer the Brazilian pirambeba for the species not genus Pygocentrus. For the true piranhas placed in genus Pygocentrus I use the epithet Caribe or Piranha. Caribe pertains to the Spanish Venezuelan piranhas but is a much more loose application since many of the piranha-like forms are also called that. But if you get a native fishermen and try to pin him down he will simply distinguish the more innocuous species with another name or the true caribe as caribe. The same holds true for epithet piranha. The native fishermen will give another name for the piranha-like and use the name piranha for the most dangerous ones in genus Pygocentrus. One last thing, native fishermen do not use scientific names in describing their fishes, we do! So we must be careful when attaching a common name to a scientifically described fish.

It has been common practice for biologists, news media and laymen to describe vegetarian fishes (pacus and tambaqui) in the genera Colossoma or Piaractus as belonging to the "piranha family" they are not! Pacus, and piranhas are all members of the Characidae family that hosts well-over 2,000 species of fish. The Characidae family (loosely called tetras) are delineated into groups or subfamilies.

There have been several unsuccessful attempts to split the sub-family into 2 groups; Mylinae (pacus and such) and the Serrasalminae (piranhas and associated forms) during the course of ichthyologic history. Norman (1929) lumped the both groups into one subfamily naming it Serrasalmoninae, but got the spelling wrong (should have been Serrasalminae.) His basis was certain characters found on both species. But the problem was much deeper than simple character assimilation. It was the advent of Phylogenetic and DNA evidence which now prevents such delineation. DnA research has also been used to separate the species with results proving confounding. Some species merged to the surprise of experts. A good case is the species Catoprion mento (the wimple piranha), this species is closest (sister) to Pygocentrus in genetic terms. Ichthyologists over the centuries have kept this particular species separate in its own ranking, but with genetics it puts it closer to the true piranhas. The wimple piranha is a good example of a species having the surname "piranha" while it is NOT a piranha by scientific definition. Most recently, genus Metynnis was discovered to be closely aligned with genus Pygocentrus using Phylogenetic and DNA sequencing.

Other species like P. denticulata, which is a piranha, have unique, specialized teeth which help it remove seed husks, much like a pacu's teeth.

TWO SCIENTIFIC OPPOSING VIEWS REGARDING CLASSIFICATION

JACQUES GÉRY

Family Serrasalmidae Classification: Dr. Jacques Géry

The French ichthyologist Jacques Géry (1972), modified the group into a new family and sub-family adding a sub-genera which further delineated the piranhas, pirambebas, and the vegetarian silver dollars and pacus;

Class: Osteichthyes
Superorder: Teleostei
Order: Cypriniformes
Suborder: Characoidei
Family: Serrasalmidae
Sub-family: Serrasalminae

genus Serrasalmus
sub-genus Pristobrycon
sub-genus Pygopristis
sub-genus Pygocentrus
sub-genus Serrasalmus
sub-genus Taddyella

Sub-family: Catoprioninae
genus Catoprion
Sub-family: Mylinae
genus Colossoma
genus Mylossoma
genus Myleus

sub-genus Myloplus
sub-genus Paramyloplus
sub-genus Prosomyleus
sub-genus Myleus
genus Uiaritichthys
genus Metynnis

genus Acnodon
genus Mylesinus

Géry split the group based on several factor's listed below

Teeth variable, usually in more than one row on upper jaw (exceptions occur in Serrasalmidae).Anal fin moderate or long, with at least 3 unbranched rays and 10 branched ones (with a few exceptions in certain regressed species).
Scales usually cycloid (with some exceptions) with circuli of caudal (apical) zone parallel or even divergent with axis of body (except Serrasalmidae).
Maxilla reduced, not toothed; dorsal fin long, with at least 16 rays; usually a predorsal spine and a series of ventral spines (serrae) (body very compressed, usually disciform; teeth variable according to diet; scales small, the circuli concentric).

ANTONIO MACHADO-ALLISON & WILLIAM L. FINK

SCIENTIFIC CLASSIFICATION PIRANHAS - Use this link.

Kingdom: Animalia

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Osteichthyes

Class: Actinopterygii

Subclass: Neopterygii

Infraclass: Teleostei

Superorder: Ostariophysi

Order: Characiformes

Family: Characidae

Subfamily: Serrasalminae

Subfamily Serrasalminae Classification - Dr. William L. Fink & Dr. Antonio Machado-Allison

The most recent evaluation of the number of species, valid names, alimentary habits and their Phylogenetic relationship with other groups was investigated by Fink and Machado-Allison (Fink, 1978; Machado-Allison, 1982a, 1985). Their present findings do not substantiate the further splitting as revised by Géry (1972). The reasoning behind this is because Phylogeny is the now the standard norm. The basic issue is that many of the older classifications, accepted non-monophyletic groups as valid to be named. There is evidence that some "pacus" are more closely related to piranhas than other "pacus" ie; that some pacus share a more recent common ancestor with piranhas than with the other pacus. That makes the group "pacus" non-monophyletic (actually paraphyletic). In relation to today's modern Phylogenetic classifications, the older methods of determining classification (or ranking) is outdated. The older classifications were not built with the Phylogenetic philosophy in mind. Right now the evidence on pacu/piranha relationships is equivocal and its doesn't seem to be useful to revise the previous classifications.

The ranks are entirely arbitrary--there is no scientific basis for any ranking procedure, so accepting a group as a subfamily or family is entirely a matter of taste. See below for further arguments.

CURRENT SERRASALMINAE SUBFAMILY GENERIC RANKING - 2009

ABSTRACT

Phylogeny of the Serrasalminae (Characiformes) based on mitochondrial DNA sequences

Previous work (Ortí et al. 1995) based on DNA sequences of mitochondrial (mt) rRNA genes showed three main groups within the subfamily Serrasalminae:

(1) a basal clade of herbivores (Colossoma, Mylossoma, Piaractus);

(2) the "Myleus" clade (Myleus, Mylesinus, Tometes);

(3) the "piranha" clade (Serrasalmus, Pygocentrus, Pygopristis, Pristobrycon, Catoprion, Metynnis). The genus Acnodon was placed as the sister taxon of clade (1+2). However, poor resolution within each clade was obtained due to low levels of variation among rRNA sequences.

D-LOOP PHYLOGENY

Complete sequences of the hypervariable mtDNA D-loop are now presented for a total of 40 taxa representing all genera in the subfamily to address intragroup relationships. Phylogenetic analyses of these sequences identify the same groupings as before and provide further evidence to support the following observations:

(a) the genera Serrasalmus and Pristobrycon are paraphyletic and form a group that also includes Pygocentrus;

(b) Catoprion, Pygopristis, and Pristobrycon striolatus form a well supported clade, sister to the group described above in 'a';

(c) distinction of subgenera within Myleus (i.e., Myleus, Prosomyleus, Myloplus) is not supported;

(d) Mylesinus and Myleus are paraphyletic, since Tometes sp. is the sister taxon of Mylesinus paraschomburgkii and Mylesinus paucisquamatus is most closely related to other species of Myleus.

Present taxonomic structure as accepted by the U.S. systematists et al. (note the different and much shorter structure from the Géry classification above):

The Tree of Life which is Phylogenetic based is controversial in many ways. It establishes a new order of animals that would not have been accepted by previous 19th and early 20th century authors.

The levels at the generic (binomen) are not subdivided into lower ranking than genus. That is the main difference with the Géry classification method which does not use Phylogenetic methods in placing his fishes and the fact he uses subgeneric ranking.

This cladogram places several vegetarian fishes into the "piranha" clade. Unthinkable during Eigenmann's time.

NEWEST INFORMATION REGARDING CREATION OF FAMILY PLACEMENT - 2008

Phylogeny of the Serrasalmidae (Characiformes) based on mitochondrial DNA sequences

Guillermo Ortí, Arjun Sivasundar1, Kelly Dietz and Michel Jégu2

School of Biological Sciences, University of Nebraska, Lincoln, NE, USA.

Abstract

Previous studies based on DNA sequences of mitochondrial (mt) rRNA genes showed three main groups within the

subfamily Serrasalminae: (1) a “pacu” clade of herbivores (Colossoma, Mylossoma, Piaractus); (2) the “Myleus”

clade (Myleus, Mylesinus, Tometes, Ossubtus); and (3) the “piranha” clade (Serrasalmus, Pygocentrus, Pygopristis,

Pristobrycon, Catoprion, Metynnis). The genus Acnodon was placed as the sister taxon of clade (2+3). However,

poor resolution within each clade was obtained due to low levels of variation among rRNA gene sequences. Complete

sequences of the hypervariable mtDNA control region for a total of 45 taxa, and additional sequences of 12S

and 16S rRNA from a total of 74 taxa representing all genera in the family are now presented to address intragroup

relationships. Control region sequences of several serrasalmid species exhibit tandem repeats of short motifs (12 to

33 bp) in the 3’ end of this region, accounting for substantial length variation. Bayesian inference and maximum parsimony

analyses of these sequences identify the same groupings as before and provide further evidence to support

the following observations: (a) Serrasalmus gouldingi and species of Pristobrycon (non-striolatus) form a monophyletic

group that is the sister group to other species of Serrasalmus and Pygocentrus; (b) Catoprion, Pygopristis,

and Pristobrycon striolatus form a well supported clade, sister to the group described above; (c) some taxa assigned

to the genus Myloplus (M. asterias, M tiete, M ternetzi, and M rubripinnis) form a well supported group whereas other

Myloplus species remain with uncertain affinities (d) Mylesinus, Tometes and Myleus setiger form a monophyletic

group.

Key words: piranhas, pacus, D-loop, phylogeny, Bayesian inference.

Received: September 13, 2006; Accepted: April 19, 2007.

INTRODUCTION

(taken from: Phylogeny of the Serrasalmidae (Characiformes) based on mitochondrial DNA sequences Guillermo Ortí, Arjun Sivasundar, Kelly Dietz and Michel Jégu, School of Biological Sciences, University of Nebraska, Lincoln, NE, USA.)

Piranhas and pacus (Serrasalmids) form a distinctive assemblage of characiform fishes. For a long time, they were considered a subfamily within the family Characidae. Recent phylogenetic studies of these fishes, however, strongly suggest that Characidae is non-monophyletic and that serrasalmids are not closely related to taxa originally placed in the subfamily Characinae, or other characid subfamilies (Zanata, 2000), but rather that they may be more closely related to Anostomoidea (Calcagnotto et al., 2005).

All these arguments support the separate family status of piranhas and pacus; their relationships to other families within the order Characiformes, however, remain uncertain (Ortí and Meyer, 1997; Calcagnotto et al., 2005; Hubert et al., 2005). Species of the Serrasalmidae are endemic to the Neotropics and are distributed widely in all the major river systems of South America. At least 60 species (in 15 genera) have been recognized. This family includes the well known piranhas, notorious from accounts of their group predatory behavior, the seed-eating tambaquí, which is highly regarded as a food species, and the pacus. Several serrasalmid species are of economic importance and are used in aquaculture (Junk, 1984; Marshall, 1995; Araujo-Lima and Goulding, 1997) . Although based on a single molecular marker (mtDNA), the results of this study carry several taxonomic implications. Most notably, many of the generic designations in the family seem to lack support or are clearly contradicted by the data. Some of these conclusions are not new: Pristobrycon striolatus has previously been regarded as quite distinct from its congeners (Machado-Allison et al., 1989), differing in several morphological aspects and its well-supported grouping with Catoprion and Pygopristis is consistent with the finding of Ortí et al. (1996)(Ortí, Sivasundar, Dietz and Michel Jégu 2008).

Our present results confirm this observation and therefore we prefer to restrict Pristobrycon to the single species P. striolatus, and place all other taxa previously assigned to this genus in Serrasalmus. According to the classification of Géry (1977), the genus Serrasalmus contained the subgenera Pygopristis, Pristobrycon, Pygocentrus, Taddyella and the nominate subgenus Serrasalmus; Serrasalmus (Pristobrycon) striolatus was noted to resemble closely the subgenus Pygopristis. This observation is well supported by our molecular analysis of control region data, as this species forms a clade with Catoprion and Pygopristis (Figure 4), and is not closely related to the other specimen putatively assigned to Pristobrycon (#224 designated Serrasalmus serrulatus here) in the rRNA tree (Figure 2). Based on various morphological characters, Serrasalmus gouldingi is distinct from other members of the genus (Machado-Allison and Fink, 1996). In this analysis, it was found to be more closely related to the remaining Pristobrycon than it is to other species of Serrasalmus. This group containing S. gouldingi, S. eigenmanni and S. serrulatus is the sister group to the Serrasalmus- Pygocentrus clade. The genus Serrasalmus contains within it the genus Pygocentrus. Results from analysis of control region sequences of a dense taxonomic sampling for Serrasalmus and Pygocentrus provides strong evidence for the monophyly of Pygocentrus but its relationship to diverse components of Serrasalmus remains unresolved (Hubert et al., 2007). Some of the poor resolution obtained in our study is evidently the consequence of poor taxonomic sampling (Ortí, Sivasundar, Dietz and Michel Jégu 2008).

Some authors (e.g. Géry, 1977) have recognized the existence of four subgenera within Myleus, namely Myloplus, Paramyloplus, Prosomyleus and the nominate subgenus Myleus, within this genus. These subgeneric distinctions have been, as with all previous classifications, based primarily on dental morphology. Other authors, however, rejected these subgeneric distinctions due to the lack of autapomoprhies (Machado-Allison and Fink, 1995). The monophyly of subgenera within Myleus is not supported by analyses of mtDNA data. Analysis of the Myleus group reveals the polyphyly of the formerly designated genus Myleus and supports the taxonomic rearrangement proposed by Jégu and Dos Santos (2002) and Jégu et al. (2003), but relationships among the various components of this group remain tentative. The group formed by Myleus setiger with Mylesinus and Tometes is relatively well-supported (PP = 1.00, BV = 67, Figure 3) suggesting strong affinities of Myleus with species designated to these genera. A robust group of Myloplus species (M. rubripinnis, M. asterias, M. tiete, and M. ternetzi) is also well supported by the control region data. As these analyses have shown, there are several taxonomic inconsistencies in this subfamily. While this study represents the most comprehensive molecular systematic treatment of this group, and utilizes a highly variable mtDNA marker to provide resolution of shallow nodes, placement of some taxa remains uncertain. In order to provide a strong foundation for taxonomic revision of the group, future studies would benefit from utilizing dense taxonomic sampling, nuclear gene sequences, together with mtDNA and morphological characters (Ortí, Sivasundar, Dietz and Michel Jégu 2008).

To read more about these new revisions contact the authors above or read the .pdf report. Not available at OPEFE web site.

Contributors and Advisers

Fink, William L.
Orti, Guillermo
Petry, Paulo

REFERENCES

Anderson S, Bankier AT, Barrell BG, de Bruijn MHL, Coulson AR, Drouin J, Eperon IC, Nierlich DP, Roe BA, Sanger F, et al. (1981) Sequence and organization of the human mitochondrial genome. Nature 290:457-465.
Aquadro CF and Greenberg BD (1983) Human mitochondrial DNA variation and evolution: Analysis of nucleotide sequences from seven individuals. Genetics 103:287-312.
Araujo-Lima C and Goulding M (1997) So Fruitful a Fish: Ecology, Conservation, and Aquaculture of the Amazon’s Tambaqui. Columbia University Press, New York, 191 pp.
Bentzen P, Wright JM, Bryden LT, Sargent M and Zwanenburg KC (1998) Tandem repeat polymorphism and heteroplasmy in the mitochondrial control region of redfishes (Sebastes, Scorpaenidae). J Hered 89:1-7.
Brown GG, Gadaleta G, Pepe G, Saccone C and SbisE (1986) Structural conservation and variation in the D-loop-containing region of vertebrate mitochondrial DNA. J Mol Biol 192:503-511.
Calcagnotto D, Schaefer SA and DeSalle R (2005) Relationships among characiform fishes inferred from analysis of nuclear and mitochondrial gene sequences. Mol Phylogenet Evol 36:135-153.
Cann RL, Brown WM and Wilson AC (1984) Polymorphic sites and the mechanism of evolution in human mitochondrial DNA. Genetics 106:479-499.
Carpenter J (1988) Choosing among equally parsimonious cladograms. Cladistics 4:291-296.
Eigenmann C (1915) The Serrasalminae and Mylinae. Ann Carnegie Mus Pittsburgh 9:266-272.
Farris JS (1969) A successive approximations approach to character weighting. Syst Zool 18:374-385.
Farris JS, Källersjö M, Kluge AG and Bult C (1994) Testing significance of incongruence. Cladistics 10:315-319.
Farris JS, Källersjö M, Kluge AG and Bult C (1995) Constructing a significance test for incongruence. Syst Biol 44:570-572.
Géry J (1972) Poissons Characoïdes des Guyanes. I. Généralités. II. Famille des Serrasalmidae. Zool Verhand 122:1-250.
Géry J (1977) Characoids of the World. T.F.H. Publications Inc, Neptune City, 672 pp.
Géry J (1984) The fishes of Amazonia. In: Sioli H (ed) The Amazon, Limnology and Landscape Ecology of a Mighty Tropical River and its Basin. Junk Publishers, Dordrecht, pp 343-370.
GoslineW(1951) Notes on the characoid fishes of the Subfamily Serrasalminae. Proc Cal Acad Sci ser 4 27:17-64.
Goulding M (1980) The Fishes and the Forest: Explorations in Amazonian Natural History. University of California Press, Berkeley, 280 pp.
Hoelzel AR (1993) Evolution by DNA turnover in the control region of vertebrate mitochondrial DNA. Curr Opin Genetics 3:891-895.
Hubert N, Bonillo C and Paugy D (2005) Does elision account for molecular saturation: Case study based on mitochondrial ribosomal DNA among Characiform fishes (Teleostei, Ostariophysii). Mol Phylogenet Evol 35:300-308.
Hubert N, Duponchelle F, Nuñez J, Garcia-Dávila C, Paugy D and Renno J-F (2007) Phylogeography of the piranha genera Serrasalmus and Pygocentrus: Implications for the diversification of the Neotropical ichthyofauna. Mol Ecol 16:2115-2136.
Huelsenbeck JP and Ronquist F (2001) MRBAYES: Bayesian inference of phylogeny. Bioinformatics 17:754-755.
Jégu M and Dos Santos GM (1990) Description d’Acnodon senai n. sp. du Rio Jari (Brésil, Amapá) et redescription d’A.normani (Teleostei, Serrasalmidae). Cybium 14:187-206.
Jégu M and Dos Santos GM (2002) Révision du statut de Myleus setiger Müller and Troschel, 1844 et de Myleus knerii (Steindachner, 1881) (Teleostei, Characidae, Serrasalminae) avec une description complémentaire des deux espèces.
Cybium 26:33-57. Jégu M, Keith P and Le Bail PY (2003) Myloplus planquettei n. sp. (Teleostei, Characidae, Serrasalminae), une nouvelle espèce de grand Serrasalminae phytophage du bouclier guyanais (Guyane française). Rev Suisse Zool 110:823-853.
Jobb G (2006) TREEFINDER, v. of May 2006. Munich, Germany, http://www.treefinder.de.
Junk WJ (1984) Ecology, fisheries and fish culture in Amazonia. In: Sioli H (ed) The Amazon, Limnology and Landscape Ecology of a Mighty Tropical River and its Basin. Dr W Junk Publishers, Dordrecht, pp 443-476.
Kocher TD, Thomas WK, Meyer A, Edwards SV, Paabo S, Villablanca FX and Wilson AC (1989) Dynamics of mitochondrial DNA evolution in animals. Proc Natl Acad Sci USA 86:6196-6200.
Leite RG and Jégu M (1990) Food habits of two species of Acnodon (Characiformes, Serrasalmidae) and scale-eating habits of Acnodon normani. Cybium 14:353-360.
Lowe-McConnel RH (1975) Fish Communities in Tropical Freshwaters: Their Distribution, Ecology and Evolution. Longman, London, 337 pp.
Machado-Allison A (1983) Estudios sobre la sistemática de la subfamilia Serrasalminae (Teleostei, Characidae). Parte II. Discusión sobre la condición monofilética de la subfamilia. Acta Biol Venez 11:145-195.
Machado-Allison A and Fink WL (1995) Sinopsis de las Especies de la Subfamilia Serrasalminae Presentes en la Cuenca del Orinoco. Serie Peces de Venezuela. Museo de Biologia, Caracas, 89 pp.
Machado-Allison A and Fink WL (1996) Los Peces Caribes de Venezuela: Diagnosis, Claves, Aspectos Ecologicos y Evolutivos. Universidad Central de Venezuela, Caracas, 149 pp.
Machado-Allison A, Fink WL and Antonio ME (1989) Revisión del género Serrasalmus Lacepede, 1803 y géneros relacionados en Venezuela: I. Notas sobre la morfología y sistemática de Pristobrycon striolatus (Steindachner, 1908). Acta Biol Venez 12:140-171.
Marshall E (1995) Homely fish draws attention to Amazon deforestation. Science 267:814.
Meyer A (1993) Evolution of mitochondrial DNA of fishes. In: Hochachka PW and Mommsen P (eds) Molecular Biology Frontiers, Biochemistry and Molecular Biology of Fishes. Elsevier Press, Amsterdam, pp 1-38.
Müller K (2005) SeqState - Primer design and sequence statistics for phylogenetic DNA data sets. Appl Bioinf 4:65-69.
Müller K (2006) Incorporating information from length-mutational events into phylogenetic analysis. Mol Phylogenet Evol 38:667-676.
Nelson, Joseph S. 1994, Fishes of the World, Third Edition xvii + 600, ISSN: 0-471-54713-1, John Wiley and Sons, New York, NY.
Nico L and Taphorn DC (1988) Food habits of piranhas in the low llanos of Venezuela. Biotropica 20:311-321.
Norman JR (1929) The South American characid fishes of the subfamily Serrasalmoninae with a revision of the genus Serrasalmus Lacepede. Proc Zool Soc London 52:661-1044.
Ortí G and Meyer A (1997) The radiation of characiform fishes and the limits of resolution of mitochondrial ribosomal DNA sequences. Syst Biol 46:75-100.
Ortí G, Petry P, Porto JIR, JéguMand Meyer A (1996) Patterns of nucleotide change in mitochondrial ribosomal RNA genes and the phylogeny of piranhas. J Mol Evol 42:169-182.
Palumbi S, Martin A, Romano S, McMillan WO, Stice L and Grabowski G (1991) The Simple Fool’s Guide to PCR. University of Hawaii, Honolulu, 46 pp.
Posada D and Crandall KA (1998) Modeltest: Testing the model of DNA substitution. Bioinformatics 14:817-818.
Rand DM (1993) Endotherms, ectotherms, and mitochondrial genome-size variation. J Mol Evol 37:281-295.
Ronquist F and Huelsenbeck JP (2003) MRBAYES 3: Bayesian phylogenetic inference under mixed models. Bioinformatics 19:1572-1574.
Saitou N and Nei M (1987) The neighbor-joining method: A new method for reconstructing phylogenetic trees. Mol Biol Evol 4:406-425.
Sambrook J, Fritsch EF and Maniatis T (1989) Molecular Cloning: A Laboratory Manual. 2nd ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor.
Starnes, William C , Characiformes - Research Curator of Fishes, North Carolina State Museum of Natural Sciences, Research Laboratory, 4301 Reedy Creek Rd., Raleigh, NC, 27607.
Swofford DL (2000) PAUP* Phylogenetic Analysis Using Parsimony (*and Other Methods), v. 4. Sinauer Assoc, Sunderland.
Thompson JD, Gibson TJ, Plewniak F, Jeanmougin F and Higgins DG (1997) The ClustalX windows interface: Flexible strategies for multiple sequence alignment aided by quality analysis
tools. Nucleic Acids Res 25:4876-4882.
Winemiller KO (1989) Ontogenetic diet shifts and resource partitioning among piscivorous fishes in the Venezuelan Llanos. Env Biol Fishes 26:177-199.
Zanata AM (2000) Estudo das relações Filogenéticas do gênero Brycon Müller and Troschel, 1844 (Characidae, Characiformes).

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