ur factsheet of the month for February 2020 examines
a species of Loricariidae that was in the past (1980s)
thought to be fairly common and was exported with
this name but on closer examination and with further
imports of other distinct looking Otocinclus,
and with further advances in taxonomic science it
was discovered that the species in question was probably
not Otocinclus affinis, but O.
similar, and imports at the time were given the name
of O. affinis. This species is not that common
in the hobby and is rarely imported and very susceptible
to pollution in its natural habitat.
can be differentiated from the genus Parotocinclus
by the absence of an adipose fin. This species is
found alongside Corydoras
prionotos and has the same colouration
as these two Callichthyidae species. It has a base
grey colour with a black band with traces of a gold
sheen (hence common name) along the flanks and has
a small hooked shaped growth on the bony plate behind
the head. Rarely imported and is rare in nature due
to pollution of its habitats. Mainly nocturnal and
feeds on algae.
There is a similar looking species further
Paulo which is larger
and probably a different species, which was placed
into a new genera, Macrotocinclus, and was
given the name Macrotocinclus
it is now reverted back to the original Otocinclus
Brazil, States of Rio de Janeiro and Espirito Santo.
O. affinis in having
s similar body pattern to Corydoras
prionotos means the mimic
is less vulnerable to predation. In this case the
predator learns to avoid the model (Corydoras)
because they have sharp fin spines tipped with a
toxin. The mimic (Otocinclus) copies that
pattern to fool the predator into thinking that
it is also a pretty painful proposition.
Brazil, vicinity of the states of Rio de Janeiro and
Espirito Santo. Type locality: Flüssen
bei S. Crux in der umgebung von Rio de Janeiro, Brazil.
Possess a small hook shaped
growth on the bony plate behind the head. No adipose
It has a base grey colour with
a black band with traces of a gold sheen (hence common
name) along the flanks.
Care & Compatibility
Peaceful, a good community
fish alongside small upper swimming inhabitants. May
have a habit of grazing on the skin of the Corydoras
sp. it may be that it is carrying out a cleaning function.Feeds
on plants and roots; in groups of 5 or more individuals;
minimum aquarium size 60cm. (24ins). Due to the catchment
area in Rio de Janeiro this Otocinclus needs
to be kept in cooler waters. Provide clean water as
they do not take too kindly to poor water conditions.
Provide a planted aqaurium for this small species.
Not recorded but
females would probably be wider in the girth especially
in breeding condition.
Algae and vegetable based foods
such as cucumber and courgette (zucchini). Will also
accept tablet food and frozen bloodworm and vegetable
based flake food.
Fleshy finlike projection without rays, behind the
rayed dorsal fin.
Oto = ear; cinclus = a latticework, (an
allusion to the holes in the head in the region of
R. and D. Pauly.
Editors. 2009. FishBase. World Wide Web electronic
publication. www.fishbase.org, version (09/2010). Evers, H.-G. & I. Seidel: Mergus,
Baensch Catfish Atlas Volume 1, 1st English edn.,
2005. Pp.944. Hardman, Michael. www.practicalfishkeeping.co.uk.