is one of two species in the Dianema genus
which we covered way back 11 years ago with Dianema
urostriatum in Factsheet
no. 29, in November 1998, and basically completes
As catfish species
go you could say that this is a plain Jane, but more
than makes up for it with its easy to keep and friendly
You can see why
it got its common name of the "Porthole Catfish"
as the sides of the body are adorned with lines of
spots akin to your normal everyday ocean going liner.
The spots on the head are that bit smaller. The top
picture shows an adult specimen while the bottom image
shows a younger specimen.
Alongside D.urostriatumthey are very difficult
to induce to spawn which is a bit of a mystery as
their counterparts in the Hoplosternum/Megalechis
genera are quite easy by contrast. They are very
easy to keep in a normal community aquarium as they
will not bother any other tankmates and as with most
catfish they will need some form of shelter such as
plants and or driftwood/pipework/stones.
adspersus, Decapogon adsperus
Brazil; Peru, Rio Ambiyacu.
Dianema is diagnosed
by the first infraorbital bone not articulating with
the lateral ethmoid; metapterygoid with an interdigitated
suture with the quadrate; and lower lip with two small
barbels on each side. Caudal fin slightly forked.
Ground colour of head and
body grey/brown, ventral region lighter. Head and
body with scatered black spots, which vary in number
and intensity. All
the fins are light tan.
Care & Compatibility
This is a peaceful midwater
to bottom swimmer that will do better if kept in a
group of at least 4 as individuals on their own tend
to sulk and never seem to progress too well. Try to
resist placing them in an aquarium with aggressive
species such as some Cichlids, they will do better
with the usual community type fish and of course along
with Corydoras sp.
This fish has
proved a challenge for quite a few catfish enthusiasts
over the years. There has been unconfirmed reports
of breeding triumphs but no documentation as yet to
prove this theory. It is reported to be a bubblenest
breeder just like its cousins in the Hoplo/Megalechis/Lepthoplosternum-complex.
Try to reduce the water level
and increase the temperature to 28°C (82°F)
to initiate breeding.
Males have marginally
thicker pectoral spines and are more slender then
Will take most aquarium fare
such as good quality flake, tablet food and frozen
food such as bloodworm.
skull bone on the anterior part of the neurocranium
forming part of the nasal cavity and located above
the vomer. Infraorbital:The
area below the eye. Name applied to the first six
circumorbital bones: suborbital 1 (lachrymal or preorbital),
suborbital 2 (jugal), suborbital 3 (true postorbital),
suborbitals 4 and 5, and suborbital 6 (dermosphenotic).
Also called infraorbital bones. Associated with the
infraorbital lateral line. Sometimes reserved for
a chain of small bones below the infraorbitals and
unrelated to the infraorbital sensory canal, e.g.
in palaeoniscoids, usually absent in advanced fishes.
Pectoral fins: The paired fins just
behind the head. Quadrate:A paired,
triangular, deep, endochondral bone on which the mandible
hinges, connecting the lower jaw to the palatine and
hyoid arches. During evolution becomes the incus bone
of the inner ear of mammals. Suture:Line of
juncture of two parts; ragged line of union between
two bones cemented with connective tissue. Supraoccipital: Unpaired bone at the back of
the skull, usually with a crest.
through; nema = thread. The gender
of this name is neuter, not feminine as usually thought. longibarbis:
Association Great Britain: Volume 1. 1983,
138p. Reis, Roberto E. 1996. Dianema Cope
1872. Version 29 April 1996. The Tree of Life Web