Perrunichthys perruno
Schultz, 1944 |
he fourth month of the new decade (2010)
brings us to another indepth look from the catfish world from
regular contributor, aquarist and author, Chris Ralph. His subject
this month is the Leopard Catfish. I now hand you over to Chris.
Perrunichthys perruno belongs
to the family Pimelodidae or Long-whiskered catfishes from South
America and is documented as being native to Venezuela and Colombia
from the Rio Negro system. The type locality for this catfish
is documented as being the Rio Negro below the mouth of the Rio
Yasa, 75km south of Rosario on the west side of Lake Maracaibo,
Venezuela, hence the reference to this catfish occurring in the
Lake Maracaibo basin.
The fact that this catfish has distinctive
markings and very long maxillary barbels make it easily identifiable.
Perrunichthys perruno is sometimes confused with Leiarius
pictus (Sailfin pimelodid) and Leiarius marmoratus
(Marble antenna catfish).
Perrunichthys perruno is a predatory fish in its natural
habitat, feeding upon any unsuspecting fish which happen to get
in the way of its relatively large cavernous mouth. Whilst these
are magnificent fish to observe they are not ideally suited to
life in captivity, unless being looked after in a large Public
Aquarium. It is suggested that the scientific name is derived
from the local name of ‘bagre perruno’ by the local
people of the Maracaibo basin (bagre is the South American name
for a catfish). I have kept a number of these catfish over the
years and have noted that they can fast for periods of time which
can be slightly worrying when this happens, and tends to coincide
after having a particularly heavy meal. The longest fast lasted
4 weeks.
Perrunichthys perruno prefer to
be kept in water which has pH in the range of pH 6.0 -7.2 and
hardness up to 18ºdGH. This catfish is ideally suited to
temperatures in the range of 22-26ºC or 72-79ºF. It
does not tolerate poor water quality, and it very important to
ensure optimum conditions are provided when keeping this species.
I would suggest a minimum size of 72”x
24”x 24”for an 18”specimen. Anything over this
size I would suggest a very large purpose built aquarium or a
heated tropical pond, or better still if you are unable to provide
adequate accommodation in the first place please do not attempt
to keep this monster catfish, magnificent as it is. As with all
other species of fish, water quality and general husbandry is
very important, especially so with large predatory fish such as
this species and I would recommend that a minimum of 25% water
is changed on a weekly basis.
With regard to the anatomical characteristics
of Perrunichthys perruno the head is described as being
greatly depressed, with a broad snout and wide sub-terminal mouth.
The body is described as being elongate and naked. The upper jaw
is described as being slightly longer than the lower jaw. The maxillary
barbels in adult specimens are described as being long, extending
to the caudal fin. This catfish has two pairs of shorter mandibular
barbels. The dorsal fin is described as having 7 soft rays. The
caudal fin is described as being large and deeply forked.
The overall base body colour of Perrunichthys
perruno is described as being dark chocolate brown with lighter
reticulated markings on the body and fins. The underside of this
catfish is much lighter in colour. The barbels have annulated
markings sharing the same body colouration. In some specimens
it has been noted that the dorsal and paired fins can sometimes
be spotted as opposed to being reticulated in terms of colour
pattern.
Wherever possible I would recommend that the
aquarist keep these catfish in a species only aquarium as individual
specimens. This catfish should not be kept with small species of
fish as they will be eaten! This catfish can be kept with other
large catfish such as Pseudodoras niger/Oxydoras niger,
Pterodoras granulosus, Megalodoras uranoscopus
(formerly M. irwini), Oscars and larger characins.
There are no documented reports of successful
aquarium spawnings of Perrunichthys perruno, this is most
likely due to the size that these fish can attain and hence the
subsequent size of aquarium in which to spawn them.
| Sexual
differences |
Generally unknown although
there are some thoughts on this subject; the males tend
to be more slender than females especially noticeable when
these catfish are in breeding condition.
|
| Feeding |
Fish and crabs are documented as being
amongst the food types consumed by Perrunichthys perruno in
the wild. In an aquarium this catfish can be persuaded to eat
pieces of dead fish, prawns, mussels, earthworms, and can even
be persuaded to eat sinking catfish pellets. This catfish is described
as being piscivorous in terms of its natural diet of fish.
| Etymology |
Perruno:
Spanish meaning canine and Greek ichthys meaning
fish. It is documented that the full name of this species
is dogfish; dog presumably in reference to its unfussy and
gregarious eating habits.
|
| Glossary
of Terms |
Caudal fin
is defined as the tail fin.
Pectoral fins are
defined as paired lateral fins.
Dorsal fin is defined
as the medial fin on top of the back.
Adipose is defined
as a second dorsal fin.
Anal fin is defined
as the medial fin immediately posterior to the anus.
Ventral fins are
defined as the paired fins between the pectoral and anal
fins.
Depressed is defined
as flattened from top to bottom.
Maxillary is defined
as being in relation to the maxilla, the bone of the upper
jaw.
Mandibular is defined
as being in relation to the mandible or lower jaw.
Annulated is defined
as having rings or belts.
Sub-terminal is
defined as being just below.
|
Author |
