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hi guys,ive always wondered how my larger cichlids are able to swollow crickets and meal worms and chomp them up,then the next day u only find legs and skins,how do they do this with out bringing up other parts of the insect,and why dont they eat all the inscet/worm,and these left over bits,legs,skins,whatever,are these harmfull to your fish and do they pollute the water fast....

Cichlids are remarkably well equipped to deal with all kinds of prey. This is because they have, in effect, two sets of teeth for chewing. First they have the teeth in the jaws. These are used principally for gripping, seizing and in some cases cutting, depending upon the food type and the shape of the teeth. Then, there are the pharyngeal teeth - these are located in arrays upon special pharyngeal bones in the throat, and provide the fish with the majority of its "chewing power" if you like.

The fact that Cichlids have been possessed of a particularly efficient pharyngeal dentition since the evolutionary ancestors split into the Cichlidae and the Pomacentridae (can't recall when this occurred, but I'd say it was no later than the Eocene, around 50 million years ago, and possibly more recent than that). This has been one of the reasons why Cichlids have moved into so many niches and prospered - the pharyngeal dentition in particular possesses a characteristic known as 'morphological plasticity', which means that over time, the shape of the pharyngeal bones and the associated teeth can change rapidly (over the course of generations) with a switch in diet. So, dedicated piscivores such as Guapotes and Boulengerochromis microlepis have their pharyngeal bones and teeth optimised for dealing with fish prey (and dealing with the bones from their prey) whilst Mbuna have their pharyngeal bones optimised for a diet of aufwuchs grazing and dealing with the small invertebrates living in the aufwuchs mats. However, if these fishes find themselves, as a result of some large scale natural event, relocated to a place where a change of diet is necessary for survival, the morphological plasticity of the pharyngeal bones comes into play again - and the bones will, over the generations, change shape to reflect the new diet. The fact that Cichlid dentition (both oral and pharyngeal) oould undergo such changes (and moreover, in some species, the oral dentition undergoes form changes from juvenile to adult just to confuse matters!) was what led Dr humphrey Greenwood in 1977 to announce that the entire phylogeny of the Cichlidae was founded upon unsafe grounds, and led to a wholesale revision of the entire Family, leading to the classification scheme we have now, extended after Greenwood's death by Sven Kullander, Dr Paul Loiselle and others.

So, given that Cichlids have adaptable mouthparts (at least over generations) and given that quite a few of the Central and South American Cichlids in particular are very partial to insect prey in the wild (your cichlids are mainly CA and SA ones if I recall Hokese!) then they'll be able to deal with insects without too many problems.

As to the debris, well, removing it is a good idea, partly because it's unsightly, and partly because it will, in time, add to the pollution load. However, the Cichlids' dentition is pretty efficient at removing digestible fleshy matter from the insect, and discarding the relatively indigestible (to the fishes that is) chitiinous exoskeleton. While the debris is mostly chitinous exoskeleton, there may be some fleshy material left behind (particularly in the legs) which will rot if not removed.

Bascailly, Hokese, your cichlids' mouthparts are well designed to take an insect, dismantle it, strip most of the juicy edible flesh from inside the exoskeleton, then separate these two fractions so that the flesh can be swallowed whilst the chitinous parts are spat out. The dexterity of the pharyngeal dentition in particular is quite something in this regard.

If you get the chance, Hokese, see if you can find some diagrams of dissected Cichlid skulls with the pharyngeal dentition marked out. You'll find it's quite something to behold.

[Edited for typos]

Panda Catfish fan and keeper/breeder since Christmas 2002

My parents used to feed our oscar crickets and
grasshoppers and nothing would be left but the
back legs.
It was quite fun to watch!


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finaly a desent answer,and yes all my cichlids are sa/ca,and thanx calilasseia for the great info,and i always remove the waste/dead bits..ive just always wondered how they do it,but now thanx to u i know,man our fish are just so cool,is there anything they cant do...

ps.hey calilasseia,i was just curious how do you know so much about heaps of different fish,im not mocking you,its just that you have such a braod knowlegde on the subject,is this from personal exp,or books/net whateva

Combination of the two Hokese ... and given that I've now been an avid student of all things fish related since I was 11, that makes for 34 years of continuous study ... you learn a lot in that time.


Panda Catfish fan and keeper/breeder since Christmas 2002

wow,no wonder u know so much,34 years in the game,thats what i call a vetran