nigripinnis (Boulenger, 1895)
his months factsheet (Sept. 2014) brings
us to the South American family Auchenipteridae and a little
known member from the Auchenipterus genera, the Paraguay
Shark-cat, Auchenipterus nigripinnis.
Your first thoughts when you see this
species is the resemblance to the shark cats of the Pangasidae
catfish family of Asia, hence its common name.
But the likeness to this family stops
there as the Auchenipterus do not grow to the huge
sizes of the Pangaidae shark cats and A. nigripinnis
will reach a manageable size of 8ins ( 20.5cm.)
The genus Auchenipterus is closely
related to and is similar to, Epapterus and Pseudepapterus.
Distinguished from all species except A.
brachyurus by the following combination of characters:
anal fin origin posterior to the middle of the body; and caudal
fin without terminal band, but with a chevron-shaped dark mask
near base of each lobe. The caudal markings are the very best
way to identify this species and from the aforementioned
which has two horizontal bands running through the caudal fin
As mentioned earlier this species is
not seen very often in the hobby and only arrived via Aquarium
Glaser in Germany in 2009, but a group of them in a large tank
will very often be seen during the day especially at feeding
time. They do not eat plants so a planted setup with added floating
plants would be advantages to this species. In its natural habitat,
it lives in the LaPlata basin of Argentina, Brazil, Paraguay,
and Uruguay so lower temperatures are the norm for this species.
Body comparatively deep, elongate; body
depth an anal fin origin 20-25% SL; body compressed, width at
anal fin origin approximately 42% (38-45%) of body depth at that
point. Barbels slender, maxillary pair extending at least to tip
of adpressed pectoral fin spine. Mandibular barbels originate
in transverse row at margin of lower jaw, just lateral to jaw
symphysis; barbels extend posteriorly at least to pectoral fin
base, basal portion of each barbel rests in shallow groove that
extends posteriorly approximately to vertical through posterior
margin of orbit. Nasal barbels absent. Caudal fin forked, lobes
pointed. Lobes somewhat asymmetrical, longest branched ray of
upper lobe longer than than that of lower lobe.
Body silvery white, grey dorsally. Abdomen
and underside of head white. Complete midlateral, posteriorly
tapering, dark stripe present in some specimens, but often stripe
extends from humeral region posteriorly only to region above pelvic
fin base. Dorsal fin with scattered dark pigmentation basally,
especially anteriorly, but pigmentation does not extend far into
fin membranes. Dorsal fin with thin dark margin in some specimens,
width of marginal pigmentation varies, but always decreases posteriorly.
Caudal fin with lightly scattered pigmentation
along margin not usually forming dark marginal bar. Middle of
upper caudal fin lobe with broad oblique, and somewhat curved
dark bar. Lower caudal fin lobe with thin dark bar, more basally
Not to be trusted with small Tetras for
instance, which will be picked of at night on its twilight patrols.
|Good community catfish
with normal sized patrons.
|Females grow larger
than the males. The males have an extended dorsal
fin. Females have a slimmer snout
than the males which is broader. As per with this family
the anal fin is modified in males with the last unbranched
and the first branched anal-fin rays elongate, enlarged,
and joined together to form the structural support of an
intromitten organ. In mature females, the last unbranched,
and 5 or 6 anterior branched, anal-fin rays are very slightly
longer than the subsequent rays.
Not reported but would be along the lines
of other members of this family. Internal fertilisation with
the eggs deposited 24-48 hours later. The eggs being encased
in a gelatine mass and placing their adhesive eggs on the underside
of wood with no broodcare after the event.
Can be fed most aquarium fare such as good
quality flake, white worm, tablet and pellet foods and frozen
foods such as bloodworm. Better to feed at lights out until they
get accustomed to the daytime feeding regime when they may very
well join in.
Auchen; auchenos = neck; pteron = wing, fin.
nigripinnis: Black fin.
median, unpaired, ventrally located fin that lies behind
the anus, usually on the posterior half of the fish.
Pertaining to the upper jaw. (maxillary barbels)
Pertaining to the lower jaw.
The paired fins just
behind the head.
The paired fins, between
the pectorals and the anal fins. (also referred to as
Standard length as measured from the snout to the caudal
The primary rayed fin(s)
on top of the body
Jr., 2007. Checklist
of catfishes, recent and fossil (Osteichthyes: Siluriformes),
and catalogue of siluriform primary types. Zootaxa 1418:1-628.
Ferraris, C.J. Jr., 1999. The South American
catfish genus Auchenipterus Valenciennes, 1840 (Ostariophysi:
Siluriformes: Auchenipteridae) : monopoly and relationships,
with a revisionary study. Zoological Journal. Vol. 126,
Part 4, 1999.
Aquarium Glaser http://www.aquarium-glaser.com/en/auchenipterus-nigripinnis_en_1070.html