Friday, November 11, 2016

[Ichthyology • 2016] Panaqolus tankei • A New Species of Tiger Pleco Panaqolus (Siluriformes: Loricariidae) from the Xingu Basin, Brazil


Panaqolus tankei 
Cramer & de Sousa, 2016


Abstract

Panaqolus tankei is described from the Xingu River, Brazil. The new species is diagnosed from P. albomaculatus, P. dentex, P. nix, P. nocturnus, and P. koko by its color pattern consisting of dark and light diagonal bars on the body and bands on the fins (vs. body and fins without bars or bands); from P. albivermis, P. maccus, and P. purusiensis by the width of the dark bars being more or less the same of the light bars (vs. dark bars at least two or three times wider than light bars) and from P. changae by the absence of vermiculation on the head (vs. vermiculation present on head). The new species differs from P. gnomus by the orientation of the bars from posterodorsal to anteroventral direction (vs. anterodorsal to posteroventral direction), and from P. claustellifer by the orientation of the bands in the dorsal fin that are not parallel to the margin (vs. parallel to the margin). The barcoding region (COI) was sequenced for the new species, sequences were deposited in GenBank and were compared with congeners from other drainages. With regard to the current construction of a hydroelectric power plant (a so-called mega dam) in the Xingu River, herewith we increase knowledge of the river Xingu’s ichthyofauna and, thus improve the assessment of the impacts of that construction on the river.


Fig 7. Live coloration of Panaqolus tankei.
(a) from the region of Vitória do Xingu (live aquarium specimen; photo by R. Heidemann) and (b) from the region of Porto de Moz with more and finer lines on the head (live aquarium specimen; photo by A. Tanke). 

Fig 10. Underwater picture of the natural habitat of Panaqolus tankei.  

Distribution and habitat: The species is only known from the lower Xingu River, downstream Belo Monte Waterfalls (Fig 8). Panaqolus tankei are usually found on fallen trees and sunken wood alongside the riverbank, in depths varying from 1 to 10 m (Figs 9 and 10).

Etymology: A patronym in honor of Andreas Tanke, a German aquarist very dedicated to the genus Panaqolus, studying its behavior, reproduction, and differences between known forms, keeping these fishes in the aquarium, visiting their habitats, and publishing his findings. He probably was the first to reproduce Panaqolus tankei in captivity. For his (successful) efforts to improve communications between aquarists and scientists to join their forces in an era of less and less money for research and an ever accelerating destruction of natural habitats.

Fig 2. Live photos of all described species of Panaqolus
Panaqolus albivermis, Panaqolus albomaculatus, Panaqolus changae,
Panaqolus claustellifer, Panaqolus dentex, Panaqolus gnomus
,
  Panaqolus koko, Panaqolus maccus, Panaqolus nix,
Panaqolus nocturnus, Panaqolus purusiensis Panaqolus tankei


(photo credits: A. Tanke [a, b, c, l], R. Heidemann [d], I. Seidel [e, h], J. Dignall [f], J. Gottwald [g], H.-G. Evers [i], E. Bertelsen [j], and C. Cramer [k]). 


Christian Andreas Cramer and Leandro Melo de Sousa. 2016. A New Species of Tiger Pleco Panaqolus (Siluriformes: Loricariidae) from the Xingu Basin, Brazil.
 PLoS ONE. 11(11); e0165388.  DOI: 10.1371/journal.pone.0165388