Chaca chaca
Frogmouth Catfish, Angler Catfish, Giant-mouth Cat, Indian Chaca, Indischer Großmaulwels (Germany), Squarehead Catfish - Chaca chaca   (Hamilton, 1822)

Article © Julian Dignall, uploaded March 01, 2001.

Truly a face only a mother could love: this month's featured catfish certainly is no looker. Unless, of course, your taste runs quite far from the norm even for a catfish enthusiast!

For me the most attractive feature of the frogmouth catfish isn't physical, it is sheer enigmatic appeal. It is hard to think of another catfish surrounded in such a surfeit of bizarre factoids, myths, assumptions and straightforward mystery, particularly amongst aquarists. Oddly for such an interesting fish it belongs to one of the smallest catfish families. With a single genus and a meager handful of species - prior to 1983 the genus was considered monotypic (contained but one species) - the family Chacidae is tiny. By contrast there really is quite a lot of ground to cover when it comes to talking about Chaca.

On the subject of "talking Chaca", this is actually the root of the generic and species name. When removed from water C. chaca makes a loud, repetitive "chaca chaca chaca" noise. Apparently C. chaca is the only frogmouth to make this noise, the other two species (C. bankanensis & C. burmensis) are silent in their alarm at being removed from the water. Fear not however, prospective Chaca owners need not pull their intended purchases from the water to determine what species they are considering. The image below shows the most reliable method of identifying C. chaca from the other two members of the genus / family. Looking at the fish close-up below, a row of numerous serrations that look like teeth (but aren't!) line the lower lip. Additionally, little growths adorn the head and body of the fish. These are only present in such numbers on C. chaca. There is a much easier way for hobbyists to tell C. chaca from C. bankanensis: the former is a chocolate brown while the latter is a brighter orange-brown. This however doesn't take into account C. burmensis, but since I haven't seen one (and don't know anyone who has) this is a useful method of differentiating the species currently imported.

Believe it or not, the mouth of the Chaca above is only about ¼ open. In the instant it takes for the frogmouth catfish to ambush their prey you only get a glimpse of its cavernous mouth. Very occasionally, Chaca will yawn. If they fully open their mouth at this time the viewer is treated to the sight of an awesome gape. This terrifying portal is also used as a bizarre method of propulsion. If these fish feel trapped and seriously threatened (and, believe me, nothing less than a major threat will elicit movement) they can quickly intake a large mouthful of water and expel it from their gills to produce a jet of water that propels the fish forward and out of danger.

One of the larger debates surrounding these fish centers on the use of this fearsome trapdoor of a mouth. Many authors believe that Chaca lure small fish to an early doom using the small, worm-like barbels at the side of their mouths. Some go as for as to suggest that the teethlets found on the lower lip also perform such a function (although are not mobile in the same way as the true barbels). Other aquarists, myself included, dispute this theory. Have a read of the Shane's World article for this side of the argument. My personal experience is only with young C. bankanensis in a retail environment, but these fish do not have the lip and body growths of C. chaca and bury themselves in such a way that their barbels / lures are often concealed beneath the substrate. These barbels also point down or at best horizontally - surely an adaptation for angling would benefit from being higher than the lower lip.

Of all the facts and oddities surrounding all frogmouth catfish, my personal favourite is that of parallel evolution. Let us leave the frogmouths native India (etc.) behind and travel to the Amazon. A very rare import indeed from South America is Lophiosilurus alexandri. This fish is yet to claim a common name, but frogmouth pim must be in the running. It is actually very similar to its Asian counterpart. L. alexandri is a Pimelodid, a family often noted for their long barbels, yet this South American has short barbels just like Chaca. In fact the whole morphology of this South American lurker is identical to that of Chaca (if scaled up a little). Its feeding strategy appears identical too. Apropos of nothing (and this is another random Chaca fact) the genus Chaca was originally assigned as Platystacus, a name now associated with the similarly inactive South American banjo catfish!

In writing this article I was able to draw on the considerable experience of Shane Linder, Dinyar Lalkaka and Klaus Dreymann. Jointly they filled the gaps resulting from my inexperience with this fish.

Brown B. A. & C. J. Ferraris 1988. Comparative Osteology of the Asian Catfish Family Chacidae, with the description of a New Species from Burma. American Museum Novitiates No. 2907: 1-16, figs. 1-9, tab. 1-2. Feb. 11, 1988.

Sane S. R. & L. R. Bhide. 1992. The Successful Spawning of Chaca chaca. Tropical Fish Hobbyist March, 1992.

Copyright information for the images used in this article can be found on the species' full Cat-eLog page.

Down Cat-eLog Data Sheet
Scientific Name Chaca chaca  (Hamilton, 1822)
Common Names Frogmouth Catfish
Angler Catfish, Giant-mouth Cat, Indian Chaca, Indischer Großmaulwels (Germany), Squarehead Catfish
Type Locality Northeastern Bengal.
Synonym(s) Chaca buchanani, Chaca lophioides, Platystacus chaca
Pronunciation CHA kah - chack ah
Etymology Chaca: The name comes from the local name of the fish, which is probably derived from the sound it makes when irritated. 
Article Link - Shane's World Right Species Right Feeding Chaca chaca
Article Link - Shane's World Right Reproduction Right Breeding Chaca
Down Species Information
Size 200mm or 7.9" SL. Find near, nearer or same sized spp.
Identification The species of the catfish genus Chaca are easily identified by their extremely large and severely dorsoventrally depressed head, caudal fin with greatly enlarged procurrent rays, and tuberculate skin, often with fimbriate skin flaps on the head and sometimes on the body. The genus forms the monotypic family Chacidae, whose phylogenetic affinities to other catfishes remains unclear despite numerous studies.

C. chaca is a chocolate brown while the similar C. bankanensis is a brighter orange-brown.
Sexing Males are larger and longer while females are shorter and more bulky.
Down Habitat Information
Distribution Asia: India, Bangladesh, Nepal, Malaya and Indonesia. Reported from Myanmar.
Indian waters, North Eastern India Waters, Padma, Ganges (click on these areas to find other species found there)
Indian waters, North Eastern India Waters, Padma, Jamuna, Brahmaputra (click on these areas to find other species found there)

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IUCN Red List Category Least Concern, range map and more is available on the IUCN species page. Last assessed 2009.
pH 6.0 - 8.0
Temperature 22.0-24.0°C or 71.6-75.2°F (Show species within this range)
Other Parameters Curiously Chaca spp. appear to lower the pH of their aquariums, much faster than the usual pH drop of a neglected tank (often to lower than pH 6.0 with no apparent ill effects to the fish). Thus regular water changes and pH testing are required particularly in a smaller species tank. Buffering may be required in some instances. Some authors report the premature death of feeder fishes that do not tolerate lower - or quick shifts in - pH levels. There is an argument that Chaca species affect their prey chemically, but I feel this is unlikely and would cause more noticeable effect in the confines of an aquarium. What is interesting to note however is that Chaca spp. are considered poisonous by locals, particularly if stepped on. Maybe we are looking at a chemical mechanism developed by a very inactive fish to taste as bad a possible to predators. Another theory still is that this excess acidity is a side effect of the strong digestive juices required by a fish that eats its prey whole.
Down Husbandry Information
Feeding Baensch states that after acclimatization pellet food is accepted. I have observed hungry young C. bankanensis eating Tetra Prima (sold in the US as Tetra colorbits) soon after import. On the contrary, long time keepers of Chaca persistently try dried or even frozen food to no avail. Perhaps only young fish will learn to accept "alternative" foods. Either way, a Chaca keeper should be prepared to supply live fish on a regular basis. User data.
Furniture A sandy substrate is suggested for all species of Chaca. Some leaf litter is appreciated by this fish although Java moss and plants that do not grow too tall are also effective. Hiding places are not required given subdued lighting.
Compatibility An irrepressible predator of small, especially bottom feeding fishes. Fast moving, surface dwelling fishes in tall tank (15''+) are unmolested. That said, anything that comes within range of a hungry Chaca's mouth will rarely survive. In my opinion, one for the species tank.
Suggested Tankmates See compatibility section.
Breeding This fish has been bred in captivity. A summary of the details follows:
Diet consisted of tubifex, shrimp, small fishes, earthworms and chopped beef heart. A group of 4 fish were kept in a 36 x 18 x 18 bare tank containing a 8'' x 3'' diameter pipe. Spawning occurs in the pipe with all other fish outside. A single (probably male) fish remained to guard the eggs, these hatched 3 days later. Parental care was not observed, yet neither was predation. 10 days after the eggs were laid the fry became free swimming. The next day they began feeding on newly hatched brineshrimp and sifted daphnia. Nearly 400 fry were raised to 1.5''. They developed steadily and uniformly among the brood.
Breeding Reports There is no breeding report.
Down Further Information
Reference An account of the fishes found in the river Ganges, pp 140, 374, Pl. 28 (fig. 43).
Registered Keepers There are 22 registered keepers, view all "my cats" data.
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There are 5 records of this fish being seen, view them all.
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Last Update 2020 Oct 05 14:27 (species record created: 2001 Mar 01 11:22)

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