Brachypopomus gauderio is not the only electric knifefish recently described from South America, U.S. researchers John P. Sullivan* and Carl D. Hopkins** have described another member of the genus Brachyhypopomus and given it the name Brachyhypopomus bullocki.

This new species is named in honour of Theodore Holmes Bullock, a renowned neurobiologist who died in 2005. Bullock was a pioneer of the comparative neurobiology of both invertebrates and vertebrates and is credited with the first physiological recordings from an electroreceptor and for championing electric fishes as a model system in neurobiology. The electric organ discharge waveform of Brachyhypopomus bullocki is biphasic, 0.9–1.6 milliseconds in duration, and the pulse rate varies from 20–80 Hz.

Brachyhypopomus bullocki is found throughout the Orinoco Basin in Venezuela and
Colombia. It can also be encountered in the in the Rio Branco drainage of Guyana and the Roraima State of Brazil, as well as in the upper part of Rio Negro near the mouth of Rio Branco.

Brachyhypopomus bullocki appears to prefer clear, shallow, standing water in open savannah, or savannah mixed with stands of Mauritia palm. It has also been collected among plants growing along the banks of small pools fed by streams. In Rio Negro, a specimen was found amongst palm leaf litter near the outlet of a black water stream.

Brachyhypopomus bullocki distinguishes itself from its close relatives by having larger eyes (comparative to the head), a short abdomen, and distally enlarged poorly ossified third and fourth branchiostegal rays.

The paper can be downloaded from Cornell University.

* John P. Sullivan, Department of Ichthyology, The Academy of Natural Sciences, Philadelphia. Email: sullivan@ansp.org

** Carl D. Hopkins, Department of Neurobiology and Behavior, Cornell University, New York. Email: cdh8@cornell.edu

Brazilian ichthyologists Julia Giora and Luiz Malabarba have described a new species of electric knifefish and named it Brachypopomus gauderio.

The fish lives in the central, southern and coastal regions of the Rio Grande do Sul state in Brazil, as well as in Uruguay and Paraguay, and its name is derived from the word “gaúcho”, a local term denoting a person living in the countryside (pampas) of the Rio Grande do Sul state, southern Brazil, Uruguay and Argentina.

Brachypopomus gauderio inhabits river banks, slow-moving creeks, lagoons, and flooded areas with muddy or sandy bottoms and has only been found among surfacing or floating plants.

You can distinguish Brachypopomus gauderio from its close relatives by its yellow dorsal surface, and on the brown markings which form a reticulate pattern.

I have not been able to find a picture.

The description has been published in the journal Zootaxa.

”Giora, J and LR Malabarba (2009) Brachyhypopomus gauderio, new species, a new example of underestimated species diversity of electric fishes in the southern South America (Gymnotiformes: Hypopomidae). Zootaxa 2093, pp. 60–68.”

A new cichlid species has been described from the Río Negro and Río Tacuarí basins in the Uruguay River drainage by Uruguay ichthyologists Iván González-Bergonzoni, Marcelo Loureiro and Sebastián Oviedo.

The fish has been given the name Gymnogeophagus tiraparae (picture here) after María Luisa Tirapare, a Guaraní woman who founded the town of San Borja del Yí (no longer existing) close to one of the collecting localities for this fish.

Gymnogeophagus tiraparae is found in larger rivers with clear water over both sandy and rocky bottoms where underwater vegetation is scarce. The fish is decorated with two horizontal series of moderately elongated light blue dots between the dorsal fin spines, and a series of light blue stripes between the soft rays, sometimes merging with the second series of elongated dots. Between the series of dots, the body of the fish displays a red ground colour. On this spotty fish, the caudal fin is also adorned with dots, which are vertically aligned on the distal border. The body has no transversal bands at all. Another important characteristic is how the adipose hump on the head is located deeper than the upper border of the dorsal fin.

The description was published in the most recent issue of the journal Neotropical ichthyology.

González-Bergonzoni, I, M Loureiro and S Oviedo (2009) A new species of Gymnogeophagus from the río Negro and río Tacuarí basins, Uruguay (Teleostei: Perciformes). Neotropical Ichthyology 7, pp. 19–24.

* Guaraní is a group of culturally related indigenous people of South America who speak the Guaraní language. They are chiefly found between the Paraguay River and the Uruguay River.

Two new species of the genus Leporinus has been described from the Araguaia-Tocantins River system in the Amazon basin: Leporinus unitaeniatus and Leporinus geminis.

Brazilian ichthyologists Julio Garavello and Geraldo Santos describe them both in a paper* published in the most recent issue of Brazilian Journal of Biology.

Leporinus unitaeniatus

Leporinus unitaeniatus derives its name from its distinguishing colour pattern; uni is the Latin word for one and taenia means ribbon. This fish is adorned with a conspicuous longitudinal dark brown bar along the lateral line on the flanks. Other distinguishing characteristics are the slender and elongated body, the narrow snout, and the small eyes. The mouth is sub-inferior and filled with elongated, incisor-like teeth forming a straight cutting edge. There are 42–44 lateral line scales; 6 scale rows above and 5 scale rows below the lateral line; and 16 circumpeduncular scales.

Picture credit: http://www.scielo.br

Leporinus geminis

Juvenile Leporinus geminis fish look very similar to juveniles of the close relative Leporinus unitaeniatus, hence the name Leporinus geminis. Geminius is the Latin word for twin.

Leporinus geminis is decorated with three large and vertically elongated brown blotches on the trunk and has one inconspicuous dark bar on the body. The body is deep, the snout is blunt, and the eyes are large. The mouth is sub-inferior and fitted with large incisor-like teeth forming a curved cutting edge. There are 40–42 lateral line scales; 5.5 or 6 scale rows above and 5 scale rows below the lateral line; and 16 circumpeduncular scales.

Picture credit: http://www.scielo.br

* Garavello, JC and GM Santos (2009) Two new species of Leporinus

Agassiz, 1829 from Araguaia-Tocantins system, Amazon basin, Brazil (Ostariophysi, Anostomidae). Brazilian Journal of Biology 69, pp. 109–116.

This post will introduce a number of new catfish species, a couple of tetras and an a few cichlid species.

Let’s start with the cichlid species. The species known as Apistogramma sp Mamore have been scientifically described by Wolfgang Staeck and Ingo Schindler and named A. erythrura. It is a small species and the largest speciemen that have been found so far was 30.8 mm SL. (just over 1.2 inch). It seems to feed on small invertebrates. Thy can be found in waters with the following conditions pH 5.2–6.4; electrical conductivity <10–20 μS/cm; total and temporary hardness < l°dH; water temperature 25.1–31.0°C. They are cave spawners and can be bred in aquariums. The male guards a territory which can contain several females. The females guard the fry.

Scientists Felipe Ottoni and Wilson Costa from Brazil have in the latest issue of the journal Vertebrate Zoology described nine new species of Australoheros cichlids from southern Brazil[1].

Australoheros autrani, A. Barbosae, A. ipatinguensis, A. macacuensis, A. muriae, A. paraibae, A.s robustus, A. saquarema

New tetras

Two new species of flag tetra have been described[2]. Both species originates in Venezuela. The new species Hyphessobrycon paucilepis and H. tuyensis was described by Carlos García-Alzate, César Román-Valencia and Donald Taphorn in the latest issue of the journal Vertebrate Zoology. At the same time they recognize three other valid species: H. diancistrus, H. fernandezi and H. sovichthys.

Hyphessobrycon paucilepis originates from the small drainages in Lara state, northern Venezuela. H. tuyensis from the Tuy River drainage in northern Venezuela

New catfish species

Brazilian scientists Héctor Alcaraz, Weferson da Graça and Oscar Shibatta have in the latest issue of the journal Neotropical Ichthyology named a new species of bumblebee catfish from Paraguay Microglanis carlae as attribute to ichthyologist Carla Pavanelli[3]. The species is found in moderately fast flowing water in Paraguay River drainage.

Brazilian ichthyologists Luisa Sarmento-Soares and Ronaldo Martins-Pinheiro have described three new Tatia species bringing the total number of described species up to twelve[4]. The three new species described are T. caxiuanensis (named after the Floresta Nacional de Caxiuanã.), T. meesi (named after Gerloff Mees) and T. nigra (named after its dark color)

T. caxiuanensis is found in the Floresta Nacional de Caxiuanã, T. meesi in Essequibo River drainage in Guyana and T. nigra in the Uatumã and Trombetas river drainages.

Marcelo Rocha, Renildo de Oliveira and Lúcia Py-Daniel have described a new Gladioglanis catfish, Gladioglanis anacanthus, which can be found in the Aripuanã River in central Brazil[5].

Lúcia Py-Daniel and Ilana Fichberg have described a new whiptail catfish, Rineloricaria daraha. This new species is found in the Rio Daráa in the Rio Negro drainage which have given the species its name[6].