hose of us that have been in the hobby for more years
that we care to mention...may recognise this species
from the Ariidae family of sea catfishes as, Arius
seemanni, and later on as Hexanematichthys
seemanni or by its favourite common name of the
These past scientific names were synonyms of Sciades
seemanni but now we are back toa new
genus name of Ariopsis. The Ariiidae family
is ever changing and it is a difficult family to pin
down as names are changing constantly once science
has caught up with descriptions.
al. (2007) in their paper, "Systematics
of the family Ariidae (Ostariophysi, Siluriformes),
with a redefinition of the genera" reclasified
quite a few species in this family and also erected
some new genera. They placed Arius seemanni in
the Sciades genus as they are the largest
number of ariid species from the eastern and western
Americas, south and southeast Asia, southern New Guinea
and northern Australia but as mentioned above it was
moved later into Ariopsis.
This is a peaceful
species when young and small specimens are not a problem
in aquaria but when they get bigger they can get restless
and slightly more aggresive and will require a larger
tank for swimming space and also a requirement for
added salt as they grow into adulthood.
The problem as
this fish grows is that it will require more salt
and from a sub-adult brackish water system they will
progress into a marine environment which will need
marine salt to be added. Another problem of course
is that your previous tropical tankmates will not
be able to tolerate the added salt and would need
to be moved to a tropical tank setup immediately.
A juncture to this is that they can get aggresive
as they mature so not really a catfish for the hobbyist
unless you know what is ahead of you and you can maitain
this species through the stages of tropical(juvenile)
brackish (sub-adult) and adult (marine). This of course
mimicks the lifestyle of this species in the wild
as they migrate from the rivers of the Pacific coast
countries of Mexico, Guatemala, El Salvador, Nicaragua,
Costa Rica, Panama, Colombia, Ecuador and Peru and
out into the sea where they can fend for themselves
as large adults.
A large tank will
be needed. 72inch or larger would be good for four
adults. Growing plants will be difficult due to the
added salt. Provide caves for hiding, a dark substrate
and low lighting. They will also need good filtration
with a swift current.
Guatemala, El Salvador, Nicaragua, Costa Rica, Panama,
Colombia, Ecuador and Peru. Type locality:
Central America (Pacific).
35cm. SL (14ins) but can grow
larger in the wild.
Broad head with a large mouth.
The eyes are large and protrude from the head. Three
pairs of barbels; one on the upper jaw and two on
Silver base colour on body
with a white underside. Fins are black with white
edges when young.
Care & Compatibility
When young they can be
combined with other brackish
water fish such as Scats and Archer Fish. When adult
they can be kept with other compatable sized Marine
Not been reported
in aquaria. They are mouthbrooders where the male
will brood them in his mouth. They will breed at the
mouth of brackish estuaries.
Females are usually
fuller in the girth than the slimmer males.
Omnivore, insect larvae, frozen
foods such as mosquito larvae, tubifex and bloodworm.
Tablet and flake foods are also taken.
Neurocranium:The portion of the skull surrounding the
brain, including the elements that surround the olfactory,
optic, orbital or sphenotic, and otic or auditory
capsules and the anterior end of the notochord (endocranium)
and the series of overlying dermal bones (dermocranium).
Also called braincase. Medial:Toward the
middle or median plane of the body; opposite of lateral.
Sensory anlage from which the ear develops; clearly
visible during early development, also: the skeleton
surrounding the inner ear or otic vesicle, composed
of the prootic, opisthotic, exoccipital, and supraoccipital.
Transcapular process: Prefix meaning
across. Fontanel: A gap between bones in
the skull, closed by a membrane, where ossification
of cartilage or connective tissue did not occur. Commonly
found on top of the skull between the frontal bones
(anterior fontanel) and between the parietal bones
R. and D. Pauly.
Editors. 2009. FishBase. World Wide Web electronic
publication.www.fishbase.org, version (10/2009). Marceniuk, Alexandre
P.; Menezes, Naércio A.
(2007). "Systematics of the family Ariidae (Ostariophysi,
Siluriformes), with a redefinition of the genera"
Zootaxa 1416: 1–126. Mongabay
Image credits: Bill
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