month of August 2012 welcomes back again the eminent
catfish author and enthusiast, Steven Grant, toinvestigate for us
another species, this time from
the Aspredinidae family otherwise known as the "Banjo
catfishes". His subject is a little known species
from the upper Amazon and Orinoco River basins, the
Shark Banjo catfish, Xyliphius lepturus.
The subject of
this factsheet is a rarely encountered Banjo Catfish.
Whereas Bunocephalus species can be found
in most aquarium shops, I have only ever seen this
species once, and another member of the genus, once.
So, if this species is rarely available one could
ask why bother providing a factsheet? Firstly, I think
this species helps to break the commonly held view
that all Banjo Catfish are sluggish fish, and also
I don’t want anyone to make the same mistake
I did, should they be fortunate enough to purchase
this species (or any Xyliphius).
Eigenman 1912 (Eigenmann used two spellings in
the original description; Xiliphius being
the other, but the former is the one used).
currently has 7 valid described species (Figueiredo
& Britto, 2010), the majority of which are found
in northern South America, with 2 being found in middle
to southern South America. There are few specimens
in museum collections and few find their way into
the aquarium hobby (more on this later). The easiest
way for aquarists to identify a Xyliphius is
the combination of a tiny eye (very difficult to spot
on some species), the triangular head/snout, and the
numerous fleshy papillae projecting off the lower
The only time
I encountered this species was approximately 2005
at a now defunct shop in West Yorkshire. I had never
seen a Xyliphius in the flesh before but
had an idea based on a photo I had seen on the Internet.
The price was comparatively high for a banjo catfish
so I could only take one.
The fish was put
in an aquarium with a sand base and an internal power
filter. It was housed with Corydoras and
loricariids. It buried in the sand during the day,
with just its mouth showing. After lights out I used
to watch the tank with a dim light. It would never
touch dry food and would only eat livefoods. I noticed
that when moving it did so in darting, jerky, side-to-side
movements, as opposed to the slower, forward, shorter
propulsion methods of Bunocephalus species.
Although it was eating, and showed no signs of disease,
it died after about 4 weeks.
for information on Banjo Cats I came across the descriptions
of all Xyliphius. Taphorn & Lilyestrom
(1983) state that Xyliphius “live in
the sand at the bottom of the turbulent rivers and
strong currents, in total darkness.” Figueiredo
& Britto (2010) state that their new species was
“captured by day in shallow waters. Due to its
diminished eyes and rough skin somewhat free from
underlying muscles, together with its extreme rarity
in collections, we speculate that Xyliphius anachoretes
is a cryptic fossorial species.” So it is clear
that Xyliphius live in moderate to turbulent
water, hiding in the sand by day, and feeding at night.
I think that had I provided a stronger water current
in the tank, my specimen would have lived much longer.
Therefore, anyone lucky enough to obtain any Xyliphius
should provide a moderate to strong current over the
sand substrate, with plenty of live or frozen food.
America: Upper Amazon and Orinoco River basins:
Colombia, Ecuador and Venezuela.
13.2cm (approx 5ins)
Dorsal fin 1/5; Anal fin 9;
Pectoral fin 1/5. Head depressed, profile of cranium
slightly rises to dorsal fin. Eyes very small. Body
after dorsal fin slightly depressed and elongated.
Strong pectoral fin spines. Skin on head with tubercles,
which on the post dorsal area of the body are arranged
Base colour is greyish white,
with the upper head and back dark grey or bluish.
Upper surface of pectoral fins, base of dorsal fin,
and midlateral anterior portion of caudal fin dark
grey or black.
Care & Compatibility
An extremely peaceful and lethargic
species. May eat fry but other than that will not
harm other fish. Should be kept with peaceful tankmates.
As yet unknown.
There are no proven external
Frozen or live bloodworm, live
Derived from the Greek word, xylephion = a little
piece of wood (referring to the woodlike appearance
of the type species of the genus). lepturus:
Derived from the Greek word leptos = thin, and the
Greek suffix -ouros (which is derived from the Greek
word oura = tail).
Anal fin:The fin forward from the anal cavity. Caudal fin: The tail. Dorsal fin: The primary rayed fin(s)
on top of the body. Pectoral fin: The paired fins after
head and before anal fin. Tubercles: Tentacle-like projections.
C. A. and M. R. Britto, 2010. A new species
of Xyliphius, a rarely sampled banjo catfish (Siluriformes:
Aspridinidae) from the rio Tocantins-Araguaia system.
Neotropical Ichthyology v. 8 (no. 1): 105-112.
Mees, G. F., 1988. The genera of the subfamily
Bunocephalinae (Pisces, Nematognathi, Aspredinidae).
Proc. K. Ned. Akad. Wet. (Ser. C Biol. Med. Sci.)
v. 91 (no. 1): 85-102. Orcés V., G., 1962. Dos nuevos
peces del género Xyliphius. Ciencia y Naturaleza
(Quito) v. 5 (no. 2): 50-54, 1 pl. [English summary]. Reis, R. E., S. O. Kullander and C. J. Ferraris,
Jr., 2003. Check list of the freshwater fishes
of South and Central America. i-xi + 1-729. Taphorn, D. C. and C. G. Lilyestrom,
1983. Un nuevo pez del genero Xiliphius (Aspredinidae)
de Venezuela. Revista Unellez de Ciencia y Tecnologia
v. 1 (no. 1): 43-44, unnumbered plate.