his member of the Callichthyidae family is a well known favourite
amongst Corydoras lovers. The 'Skunk' or 'Arched Cory'
is sometimes difficult to pick up in the shops and seems to come
and go in periods so you have to snap them up when seen and of
course the recently unfolding story of the true C. arcuatus
is told below.
Water conditions are of paramount importance
on this species as the barbels are very susceptible and can very
quickly wear away if the water changes are not adhered to and
the bacteria builds up in the substrate, why this species of Corydoras
is effected more than any other is a mystery to me.
In the following picture you can see the worn down barbels on
this species. Sand would probably be a good bet for the bottom
of their tank, just a light scattering should suffice.
This species is sometimes confused with
its longer nosed cousin Corydoras narcissus,
but the length of the snout is the main difference, and also the
stripe in narcissus tends to be longer, running into the
lower lobe of the caudal fin.
This species was given the CW-number (Corydoras World) of 36 as
it had not previously been given a C-number. It is now thought
(Grant, S. 2014) that this species, CW036, is the true Corydoras
arcuatus instead of the shorter nosed C020.
Above is a young speciman, (C020) and as
it grows the black spots will join up to show the adult black
It is now been proven (Grant, S. 2014) that
CW036 is the true Corydoras
arcuatus instead of C020.
Dorsal 1/7; Anal 1/6;
22-24 bony scutes in the upper lateral series, 20-22 in the lower.
Grey-yellowish to delicate grey-green; underside
pure white. A broad, dark longitudinal band commences at the corner
of the mouth and passes across the eye into an arched course following
the profile of the back to the root of the tail where it turns abruptly
downwards and, becoming narrower, continues along the lower edge
of the caudal fin. No other markings. Fins colourless; caudal with
fine dark spots and a blackish upper edge.
Will do well in a community setup with smaller
tankmates such as Rasboras and Tetra's. Do not house with aggressive
species or large Cichlids.
Not one of the easiest cory's to breed, but
in one reported spawning a cold water change down to 60f (17c) induces
spawning, with the eggs being laid in Java Moss. Eggs will hatch
in 3 to 4 days. U.K. Corydoras breeder Ian Fuller of the
World web site has bred this species in 1980 and reported the
usual Cory T-mating clinch fashion. 110 eggs were laid with about
65 of them in the Java moss the remainder were stuck on the sides
of the tank mainly in the corners. Temperature was 68f (20c) and
the eggs hatched in 3 to 4 days. There was a 95% hatch rate.
30 years later in 2010 In Scotland, aquarist
Graham Ramsay has also bred this species. See
breeding article on breeding the afore mentioned species C020 here
After the fry are 3 days old, feed microworm,
fry flake then progress on to brineshrimp, keeping up the water
changes. Adults can be fed on the usual good quality aquarium flake
with tablet food and frozen bloodworm being a good diet.
Catfish, An Aquarists Handbook 1995
Cory = helmeted; doras
= leathery skin,(helmeted Doras) cuirass.
arcuatus : Arched, like a bow, (referring
to the stripe)
Sterba, Günther; Freshwater fishes
of the World Vol.1 1973
Fuller, A.M. Ian, Breeding
2014, Catfish Study Group Journal V15 - I4
© Ian Fuller @