Two new tetras found

8d21454c-2e03-401f-8516-b5dff8d04e4a

Editor's Picks
Features Post
The brightest pupils
04 October 2021
Features Post
Dealing with egg ‘fungus’
04 October 2021
Features Post
Rathbun’s tetra in the wild
13 September 2021
Fishkeeping News Post
Report: 2021 BKKS National Koi Show results
13 September 2021
Features Post
The World's forgotten fishes
16 August 2021


Two new species of tetra from the Astyanax genus have been discovered in Brazil.

The new characins, which are members of the family Characidae, have been named Astyanax microschemos and Astyanax pelecus by Vinicius Bertaco and Carlos de Lucena in a paper in the journal Neotropical Ichthyology.

A. microschemos was found in the Corrego Palmital area of the Rio Itapemirim drainage, while A. pelecus was found in the Rio Pardo drainage in Bahia, Brazil.

Astyanax microschemos has a massive head, shallow body, short snout and a vertically-elongated black humeral spot, which is a characteristic of the members of the Astyanax scabripinnis group.

Astyanax pelecus has a humeral spot above the lateral line, as well as a dark stripe running along the middle of its flanks from the edge of the gill cover to the base of the tail.

Both species also have some morphomeristic features that set them apart from other Astyanax species.

A. microschemos has a shallower body depth than others, at around 26.9-29.7% of its body length, it also has 14-18 branched anal rays and a smaller interorbital width.

Astyanax pelecus differs from other Astyanax species by a body depth of 26.7-34.8% of standard length, 16-18 branched anal rays and 38-39 scales in the lateral line series.

For more information on the new tropical fish species see the paper: Bertaco VA and CAS de Lucena (2006) - Two new species of Astyanax (Ostariophysi: Characiformes: Characidae) from eastern Brazil, with a synopsis of the Astyanax scabripinnis species complex. Neotropical Ichthyology, 4(1):53-60, 2006.

Astyanax species distributionsThe members of the Astyanax genus are quite widespread through South and Central America and the genus currently contains around 90 valid species. You can view the distributions of some of these fishes on Practical Fishkeeping's Fish Mapper application.

Astyanax abramis

Astyanax alburnus

Astyanax altiparanae

Astyanax angustifrons

Astyanax anterior

Astyanax argyrimarginatus

Astyanax armandoi

Astyanax asuncionensis

Astyanax atratoensis

Astyanax bimaculatus

Astyanax bourgeti

Astyanax brachypterygium

Astyanax brevirhinus

Astyanax caucanus

Astyanax chaparae

Astyanax cordovae

Astyanax correntinus

Astyanax cremnobates

Astyanax daguae

Astyanax depressirostris

Astyanax eigenmanniorum

Astyanax erythropterus

Astyanax fasciatus

Astyanax fasslii

Astyanax festae

Astyanax filiferus

Astyanax gisleni

Astyanax giton

Astyanax goyacensis

Astyanax gracilior

Astyanax guaporensis

Astyanax guianensis

Astyanax gymnogenys

Astyanax hastatus

Astyanax integer

Astyanax intermedius

Astyanax ita

Astyanax jacuhiensis

Astyanax janeiroensis

Astyanax jenynsii

Astyanax jordani

Astyanax kennedyi

Astyanax kompi

Astyanax kullanderi

Astyanax latens

Astyanax laticeps

Astyanax leonidas

Astyanax leopoldi

Astyanax lineatus

Astyanax longior

Astyanax maculisquamis

Astyanax magdalenae

Astyanax marionae

Astyanax maximus

Astyanax megaspilura

Astyanax mexicanus

Astyanax microlepis

Astyanax multidens

Astyanax mutator

Astyanax myersi

Astyanax nasutus

Astyanax nicaraguensis

Astyanax obscurus

Astyanax ojiara

Astyanax orbignyanus

Astyanax orthodus

Astyanax paraguayensis

Astyanax parahybae

Astyanax paranahybae

Astyanax paris

Astyanax pelegrini

Astyanax poetzschkei

Astyanax pynandi

Astyanax ribeirae

Astyanax robustus

Astyanax ruberrimus

Astyanax saguazu

Astyanax saltor

Astyanax scabripinnis

Astyanax schubarti

Astyanax scintillans

Astyanax stenohalinus

Astyanax stilbe

Astyanax superbus

Astyanax symmetricus

Astyanax taeniatus

Astyanax trierythropterus

Astyanax troya

Astyanax turmalinensis

Astyanax unitaeniatus

Astyanax validus

Astyanax venezuelae

Astyanax villwocki