Can anyone tell me how to differentiate between the two? I've thoroughly examined all the pics of the bristlenose pl*cs in the database and (with the additional information from my LFS) have narrowed the field down to one of the two (although I have a young female and am unable to compare the tentacles).
Any information would be appreciated & thanks in advance
in real life, but judging from the picture here at Planetcatfish one obvious difference is that the spots are of approximately equal size over the entirety of the body, while
I'd love someone to do some biochemical systematic work on Ancistrus species- my gut feeling is that we're more or less dealing with different regional populations of what was fairly recently a single species in many cases; deciding when different populations are different enough to merit species status is more a judgement call than an exact science. Years ago it used to be fairly common to see populations identified as subspecies or races, but that almost never seems to be the case with fish now.
The single picture of cirrhosus in the CateLog is a dead ringer for some of my juvenile "common" bristlenoses (previously Ancistrus sp.3), but common bristlenoses colleagues of my local society have posted photos of seem to show a fair degree of variation, especially with mature males.
Thanks Mats- I had seen that (this lunchtime), and it looks like a "definite maybe" as an id for common bristlenose, although whether we'll ever be sure enough to drop the "cf" is open to question. It would be nice to see more pictures of the presumed true cirrhosus from Ingo, as they grow if Ingo's wild stock mentioned in the article are all the same age. The locality being Argentina may well be the reason they've not been reimported (at least not regularly) in modern times.
I'll tentatively classify my female as A. 'Columbia' since she most resembles the pic in the Cat-eLog.
Unless you are 100% sure the fish is wild-caught and from Colombia, there is little justification in regarding the fish as A. sp. "Columbia" in my opinion.
The common bristlenose is quite variable with regard to spot size, so this character shouldn't be relied upon.
Like Mike, I have never seen imports of this Ancistrus from Colombia.
Just reclassified as cirrhosus since some of the patterning towards her tail has indeed become slightly larger, but the rest of her spots/features remain the same. Thanks everyone!
