A redescription of Astyanax gymnodontus (Eigenmann, 1911), new combination, a polymorphic characid fish from the rio Iguaçu basin, Brazil

Pavanelli, Carla Simone; Oliveira, Carlos

doi:10.1590/s1679-62252009000400003

Cited by 14 publications

(16 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At least two described species fits on the species delimitation of "Astyanax sp. F." proposed by those authors: A. varzeae and A. gymnodontus (see Pavanelli & Oliveira, 2009 for comments on A. gymnodontus). The new species herein described also seems to fit to the feeble definition of "Astyanax sp.…”

Section: Discussionmentioning

confidence: 99%

“…The rio Iguaçu basin is known by its high ichthyofaunistic endemism (Haseman, 1911;Garavello et al, 1997;Ingenito et al, 2004;Baumgartner et al, 2006;Ingenito et al, 2008;Alcaraz et al, 2009;Abilhoa & Duboc, 2007;Garavello & Sampaio, 2010), especially concerning to genus Astyanax (Pavanelli & Oliveira, 2009). Among the 14 species of Astyanax reported from the rio Iguaçu basin, 13 are endemic to the basin, with some of them only occurring in smaller sub-basins (e.g.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

A new species of Astyanax (Ostariophysi: Characiformes: Characidae) from the upper rio Iguaçu basin, southern Brazil

Ingenito¹,

Duboc²

2014

Neotrop. ichthyol.

864

View full text Add to dashboard Cite

Astyanax eremus, a new species of geographically isolated characid fish, is described from a small tributary of the upper rio Iguaçu basin. The new species belongs to the Astyanax scabripinnis species complex and is easily distinguished from its congeners included in this group by its allometric growth of the mouth, which goes from terminal in young individuals to subterminal mouth in larger specimens. Additionally, the new species is distinguished by meristic and morphometric characters. Astyanax eremus presents an evident polymorphism on the traditional character "number of teeth in inner premaxillary row". Comments about that character are provided.Astyanax eremus, uma espécie nova de caracídeo geograficamente isolada, é descrita de um pequeno tributário da bacia do alto rio Iguaçu. A espécie nova pertence ao complexo de espécies Astyanax scabripinnis e é facilmente distinguível dos congêneres deste grupo por apresentar desenvolvimento alométrico da boca, a qual passa de terminal nos indivíduos jovens a subterminal nos maiores. Além disso, a espécie nova é diagnosticada por caracteres merísticos e morfométricos. Astyanax eremus apresenta um acentuado polimorfismo do tradicional caráter "número de dentes da série interna do pré-maxilar". Uma discussão a respeito deste caráter é apresentada.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

A new species of Astyanax (Ostariophysi: Characiformes: Characidae) from the upper rio Iguaçu basin, southern Brazil

Ingenito¹,

Duboc²

2014

Neotrop. ichthyol.

864

View full text Add to dashboard Cite

show abstract

“…Vertebral count includes the four vertebrae of the Weberian apparatus and the fused PU1 + U1 as a single element.Counts observed in the syntype series are marked with an asterisk. Meristic data for other species of Astyanax were taken for direct examination of specimens (see Comparative material) or from original description or redescriptions (e.g., Eigenmann, 1927;Garutti, 2003;Melo & Buckup, 2006;Pavanelli & Oliveira, 2009 Description. Morphometrics presented in Table 1.…”

Section: Methodsmentioning

confidence: 99%

“…Similarly increasing are the contributions through redescriptions of poorly known species (e.g., Garutti, 2003;Mirande et al, 2006;Garutti & Langeani, 2009;Pavanelli & Oliveira, 2009;Azpelicueta & Loureiro, 2009;Almirón et al, 2010;Bertaco & Lucena, 2010;Soneira et al, 2010).…”

Section: Introductionmentioning

confidence: 96%

Redescription of Astyanax multidensEigenmann, 1908 (Characiformes: Characidae), a small characid of the Brazilian Amazon

Marinho

Birindelli

2013

Neotrop. ichthyol.

View full text Add to dashboard Cite

Astyanax multidens is redescribed based on syntypes and additional specimens from the rio Amazonas at Silves, Amazonas State and Óbidos, Pará State, and the rios Trombetas, Tapajós, Xingú, and Araguaia. Astyanax multidens is distinguished from congeners by the unique combination of five to seven maxillary teeth, 31 to 34 pored lateral-line scales, 20 to 23 branched analfin rays, and a dark triangular blotch restricted to the middle caudal-fin rays. Astyanax multidens was collected syntopically with Jupiaba paranatinga in the rio Tapajós basin and with Jupiaba cf. essequibensis in the rio Xingu basin, which have paired anteriorly oriented pelvic-fin spines, a antipredatory mechanism. Based on the external morphological similarity between Astyanax multidens and the two species of Jupiaba, their sympatric occurrence, and their distinct phylogenetic position, we interpret this a case of Batesian mimicry.Astyanax multidens é redescrita com base no exame dos síntipos e espécimes adicionais do rio Amazonas em Silves, AM e Óbidos, PA e rios Trombetas, Tapajós, Xingú e Araguaia. Astyanax multidens distingue-se dos congêneres pela exclusiva combinação de cinco a sete dentes no maxilar, 31 a 34 escamas perfuradas na linha lateral, 20 a 23 raios ramificados na nadadeira anal, e uma mácula triangular escura restrita aos raios medianos da nadadeira caudal. Astyanax multidens foi coletada sintopicamente com Jupiaba paranatinga na bacia do rio Tapajós, e com Jupiaba cf. essequibensis na bacia do rio Xingu, que possuem espinho pélvico voltado para frente, um mecanismo antipredatório. Baseado na similaridade morfológica externa entre Astyanax multidens e estas duas espécies de Jupiaba, sua ocorrência simpátrica, e sua distante posição filogenética, nós interpretamos como um caso de mimetismo Batesiano.

show abstract

“…F and Psalidodon gymnodontus, Pavanelli and Oliveira (2009) gathered these two species in a single one called Astyanax gymnodontus (Eigenmann, 1911). For this species, literature reports that it feeds primarily on terrestrial insects, also eating plants and other fish (Hahn, Fugi, Almeida, Russo, & Loureiro, 1997;Cassemiro, Hahn, & Delariva, 2005;LoureiroCrippa & Hahn, 2006).…”

mentioning

confidence: 99%

Population structure and reproductive biology of Astyanax gymnodontus (Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil

Baumgartner

Silva²,

Baumgartner

2016

RBT

View full text Add to dashboard Cite

Success in fish breeding depends on reproduction intensity, periodicity and the place where it occurs. Information about fish species reproduction is important to assist managers, and to determine conservation and management strategies. The fish assemblage of the Iguaçu River basin is already known for its high endemism, and despite this privilege, the large number of dams built along it, threat this particular biodiversity. Astyanax gymnodontus is an endemic fish species and studies on its population structure and reproductive biology are important, since they represent the first step for further community studies. Our objective was to evaluate some aspects of the population structure and reproductive biology of A. gymnodontus in the influence area of Salto Santiago dam, Iguaçu River, Paraná State, Brazil. Sampling was made monthly from July 2003 to June 2005, and bimonthly from July 2005 to March 2013, at five sites in the influence area of Salto Santiago dam. Fishes were collected using 10 m length gillnets with meshes ranging from 2.5 to 6.0 cm between non-adjacent knots and trammel nets with inner meshes of 6.0 cm between non-adjacent knots. Nets were arranged on surface, bottom and margins of each site, exposed for 24 h. Additional drags on littoral areas were performed from January to March and October to December from 2009 to 2011, with 50.0 m nets, 0.5 cm mesh size, for juveniles capture. We captured and analyzed 21 932 individuals, being 9 249 females and 12 683 males, representing 42.2 % and 57.8 %, respectively. The average body length was 8.8 cm for females and 8.3 cm for males. The average weight was 18.8 g for females and 16.0 g for males. Sex ratio calculated for the entire period was 1.8 males/female. Males were more abundant than females in 73.2 % of samples and significant differences were observed in 35.3 % of samples. The estimated length at first maturity (SL 50 ) was 6.4 cm for females and 6.2 cm for males. We suggest that sexual differences in body length and weight, and sex ratio occurred as a result of sexual differences in energy allocation. Females spend more energy on body growth, which means more eggs production and higher fecundity. As an integrated response, males spend more energy on sperm production, in competition with other males, leading to a smaller body size. Differences in estimated SL 50 might be an indicator of this sexual difference in energy allocation. The reproduction period was from September to February, with greater intensity at the beginning of this period, and the sites of highest reproductive intensity were those immediate downstream from dams, and therefore with more riverine characteristics. Rev. Biol. Trop. 64 (1): 69-77. Epub 2016 March 01.

show abstract

A redescription of Astyanax gymnodontus (Eigenmann, 1911), new combination, a polymorphic characid fish from the rio Iguaçu basin, Brazil

Cited by 14 publications

References 12 publications

A new species of Astyanax (Ostariophysi: Characiformes: Characidae) from the upper rio Iguaçu basin, southern Brazil

A new species of Astyanax (Ostariophysi: Characiformes: Characidae) from the upper rio Iguaçu basin, southern Brazil

Redescription of Astyanax multidensEigenmann, 1908 (Characiformes: Characidae), a small characid of the Brazilian Amazon

Population structure and reproductive biology of Astyanax gymnodontus (Characiformes: Characidae), a poorly known endemic fish of the Iguaçu River basin, Brazil

Contact Info

Product

Resources

About