Silva GSC, Ochoa LE, Castro IS, 2022
contributors to this species:
Dario Faustino-Fuster (3)
Phenacorhamdia suia differs from all congeners
by having an atypical mottled coloured body (vs. uniformly
counter-shaded, without mottled pattern; with a longitudinal
dark brown stripe along the dorsal half of the body
in P. unifasciata), and by having all fins
with interradial membranes pigmented and mottled (vs.
fins with interradial membranes hyaline). Additionally,
P. suia differs from all congeners, except
P. taphorni by having multicuspid teeth (vs.
conical teeth). The new species differs from some
of its congeners by maxillary barbel reaching pectoral-fin
origin (vs. maxillary barbel reaching the end of adpressed
pectoral fin in P. anisura, P. boliviana,
nigrolineata, and P.
half the length of pectoral fin in P. tenuis;
surpassing pectoral fin in P. provenzanoi
and P. taphorni; reaching pelvic-fin origin
macarenensis); lacking a short
extension of the first pectoral-fin ray (vs. present
in P. anisura, P. macarenensis,
P. nigrolineata, P. provenzanoi,
and P. taphorni), by caudal fin deeply forked
with extremely elogated and pointed lobes (vs. moderately
pointed in P. hoehnei; rounded in P.
somnians); and by having 43-45 total vertebrae
(vs. 39 in P. taphorni; 41 in P. hoehnei;
41-42 in P. tenebrosa; 46-47 P. unifasciata;
47-48 in P. provenzanoi; 53-55 in P.
tenuis). Habitat: Phenacorhamdia
suia is known from nine localities from the upper
and lower Xingu River basins. The type-locality is
Santa Luzia stream, Comandante Fontoura River basin.
Other sites are Culuene, Coronel Vanick, Suiazinho,
Turvo Rivers, Capim and Fonte Boa streams, and two
unnamed streams. Colouration:
Overall pigmentation mottled (with light brown background
and irregular dark brown blotches formed by minutes
and concentrated melanophores that overlap each other),
becoming ventrally mostly unpigmented. Interradial
membranes of all fins pigmented as the body. Etymology:
The specific name “suia” refers to the
Suias indigenous people who, since the 90’s,
have stood out in the fight to protect the Suiá-Missu
River environment and for recovery of their traditional
lands outside the limits of Xingu park. A noun in
apposition. Holotype: 81.8 mm SL.
Upper and lower Xingu River basins, Brazil. Type
locality: Santa Luzia stream, Comandante
Fontoura River basin.
Silva, Gabriel S. C.,
Ochoa, Luz E. and Castro, Íthalo S.
New species of Phenacorhamdia (Siluriformes: Heptapteridae)
from the Xingu River basin. Neotropical Ichthyology