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or our 350th factsheet of the month for August 2025, we focus on the Doradidae family and a member of the not-so-common species Trachydoras paraguayensis. You can fathom, of course, where this catfish resides from the specific name of paraguayensis, Paraguay, of course, and hailing from the Paraná River basin, Paraguay, Brazil, Argentina, and Bolivia. The type locality is in Corumbá, Brazil, just north of the Paraguayan border in the Paraguay River.

    Trachydoras paraguayensis

Trachydoras paraguayensis occurs in the Madeira (Amazon Basin) and Paraguay River basins. The species also appears in the Middle and Lower portions of the Paraná basin. It stretches throughout Brazil, Bolivia, Paraguay and Argentina. In 1982, the species was introduced in the upper portion of the Paraná basin following the filling of the Itaipú reservoir (Sabaj and Hernandéz 2017). The type locality has always stated being in Corumba, Paraguay, but this catch location is in Brazil, where it borders Paraguay to the south and Bolivia to the west.

None

Hemidoras paraguayensis

Doradinae

South America: Paraná River basin Paraguay, Brazil, Argentina, Bolivia. Type locality: Corumba, Brazil.

19.0cm. (7½ins)

20-26°C (67-79°F)

Body deep; greatest body depth contained 2.7 to 3.1, head length 3.3 to 3.8 times in SL; snout length contained 1.9 to 2.2, horizontal orbital diameter 2.5 to 3.1 and least interorbital width 2.2 to 2.8 times in HL; orbital diameter contained 1.0 to 1.3 times in interorbital width. Mouth subterminal; with dentigerous plates in both premaxilla and dentary. Lateral line with 28-30 plates. Dorsal fin with I,6, pectoral fin with I,7, pelvic fin with 7 and anal fin with 12-14 rays. (Graça, Pavanelli, 2007).

Peaceful species for a mid sized community tank, planted with hiding places such as pipes or driftwood/bogwood.

Females are deeper and wider bodied.

Tablet and pellet foods, frozen bloodworm and live foods should keep this catfish in good condition.

Anal fin: The median, unpaired, ventrally located fin that lies behind the anus, usually on the posterior half of the fish.
Caudal fin: The tail.
Dorsal fin: The primary rayed fin(s) on top of the body.
Hyaline: Transparent or clear without pigment.
Lateral line: A sensory line, along the sides of the body.
Pectoral fin: The paired fins just behind the head.
Pelvic fin: The paired fins, between the pectorals and the anal fins (also referred to as ventrals).
Premaxilla: In relation to the premaxilla (an upper jaw bone) e.g. premaxillary tooth band.

Trachydoras: Trachýs (Gr.), jagged or rough, referring to granular opercle, preopercle and coracoid-process; Doras, type genus of family.
paraguayensis: –ensis, Latin suffix denoting place: Corumba, Paraguay, (Brazil!) type locality.

Photo Credits

©    Allan James @ courtesy of  

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