Diagnosed among congeners by having the distal tip
of the anterior branched dorsal-fin rays and membranes
darkened (vs. distal tip of anterior branched dorsal-fin
rays and membranes pale). Hassar affinis
is distinguished from H.
wilderi by having two rounded
diverticula restricted to each side of anterior chamber
of gas bladder (rarely one extra pair on posterior
chambers) (vs. many well-branched diverticula along
margins of entire gas bladder); and gas bladder rounded
posteriorly (vs. gas bladder triangular posteriorly,
each posterior chamber extended into a short terminal
diverticulum sharing medial septum with its pair).
Hassar affinis is further distinguished from
H. orestis by having 12th through 17th, modally
13th, midlateral scute as the anteriormost with median
thorn (vs. 1st through 8th, modally 3rd), 10th midlateral
scute 3.1-5.1%, mean 4.1%, of relative body depth
(vs. 6.2-18.0%, mean 12.9%, of relative body depth),
and tip of upper caudal-fin lobe not darkened (vs.
usually darkened). Hassar affinis is distinguished
gabiru by having lateral diverticula
on gas bladder rounded (rarely branched in large specimens)
(vs. lateral diverticula finger-like, weakly-branched
in large specimens). Aquarium Care:
For a large species it is non aggressive and can be
kept with smaller species such as small characins,
dwarf cichlids, small labyrinth species and also other
small catfish such as Corydoras and the smaller
members of the Loracariids. Provide a soft substrate
such as fine sand as they like to sift through this
for edibles and a sharp substrate could cause damage
to its fine feathered barbels. Lone individuals will
not do well in an aquarium setup so a group of three
or more will be more beneficial to the long term health
of this species. A planted aquarium is a must as they
like to hide in the roots more so than having a rock
or wood setup. Diet: Tablet foods,
small live and frozen foods such as worms and Daphnia.
Oxydoras affinis, Hassar
woodi, Hassar iheringi
Parnaíba River basin, Brazil. Type
locality: Rio Parnahyba, Therezina, Piauhy
Birindelli, J.O., D.F.
Fayal and W.B. Wosiacki,
2011. Taxonomic revision of thorny catfish genus Hassar
(Siluriformes: Doradidae). Neotrop. Ichthyol. 9(3):515-542. Ferraris, C.J. Jr., 2007. Checklist
of catfishes, recent and fossil (Osteichthyes: Siluriformes),
and catalogue of siluriform primary types. Zootaxa
1418:1-628. Froese, R. and D. Pauly. Editors.
2018. FishBase. World Wide Web electronic publication.
www.fishbase.org, ( 06/2018 ). Sabaj, M.H. and C.J. Ferraris Jr.,
2003. Doradidae (Thorny catfishes). p. 456-469. In
R.E. Reis, S.O. Kullander and C.J. Ferraris, Jr. (eds.)
Checklist of the Freshwater Fishes of South and Central
America. Porto Alegre: EDIPUCRS, Brasil.