Brazilian scientists have described a new species of pimelodid catfish from the Paran River drainage in southern Brazil.
Julio Garavello and Oscar Shibatta describe the new species as Pimelodus britskii in a paper in the latest issue of the journal Neotropical Ichthyology.
The new species is named after eminent Brazilian ichthyologist Heraldo Britski in recognition of his contribution to Neotropical ichthyology, and is distributed broadly throughout the Iguau River, a tributary of the Paran River.
Pimelodus britskii reaches a size of 297 mm SL and can be distinguished from other members of the genus except P. fur, P. heraldoi and P. absconditus in having a colour pattern consisting of small densely-placed oval or circular dots on the anterior region of the trunk, becoming inconspicuous or disappearing on the caudal peduncle.
It differs from P. fur in having a longer maxillary barbel, snout and post-orbital distance, larger eye set further apart, and wider mouth; from P. heraldoi in having a shorter predorsal length, more slender caudal peduncle, longer snout and post-orbital distance, larger eye set further apart, and wider mouth; and from P. absconditus in having shorter predorsal and prepelvic distances, more slender caudal peduncle and narrower pectoral girdle.
The new species was previously confused with P. ortmanni, because the type series of P. ortmanni consisted of specimens of both P. ortmanni and P. britskii.
The authors write: Haseman...incorrectly attributed the differences in color pattern observed within the type series of Pimelodus ortmanni to variation during ontogenetic development.
Our examination of the P. ortmanni type series and the additional fresh material revealed that each species maintains a characteristic color pattern throughout ontogeny...The presence of two species in the type series, with variation in the color pattern, may explain why the oriinal description of P. ortmanni is so imprecise.
Because the figure of P. ortmanni is more informative than the description, subsequent authors have been misled in the identification of Pimelodus ortmanni...
For more information, see the paper: A new species of the genus Pimelodus La Cpde, 1803 from the rio Iguau basin and a reappraisal of Pimelodus ortmanni Haseman, 1911 from the rio Paran system, Brazil (Ostariophysi: Siluriformes: Pimelodidae). Neotropical Ichthyology 5, pp. 285"292.