his 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 the set!.
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 demeanor.
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
Alongside D. urostriatum
they 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.
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.
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
to initiate breeding.
Will take most aquarium fare such as good
quality flake, tablet food and frozen food such as bloodworm.
|Males have marginally
thicker pectoral spines and are more slender then the females.
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.
Ethmoid: Unpaired skull bone on the anterior
part of the neurocranium forming part of the nasal cavity
and located above the vomer.
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
Dia = through;
nema = thread. The gender of this name is neuter,
not feminine as usually thought.
E. 1996. Dianema Cope 1872. Version 29 April 1996
(under construction). http://tolweb.org/Dianema/15337/1996.04.29
in The Tree of Life Web Project, http://tolweb.org/
Catfish Association Great Britain: Volume
1. 1983, 138p
First image: Allan
Second image: Mark