ID Assist - "A. agassizii Alenquer"

[Jonathan A]

One of my LFSs got in some A. agassizii-complex fish in from an Asian supplier. They were sent as A. agassizii "alenquer" and definitely appear to have the Netz patterning on the scales. The males' caudal fins were pretty rounded, but I'm not sure if that's typical of any location/strain or just a factor of age. I didn't see any irregular scale sizes/patterns or the like which could point to hybridization (afaik).

I know A. agassizii is a big ol' mess at the moment, but any more specificity is always appreciated.

 

[Frank Hättich]

The patterning on the scales in fact points to one of the Netz-forms. But unlike this fish, the Netz-forms usually develop quite long tips on the dorsal, anal and caudal fins. However, there can be quite some reasons why this isn't the case here, in particular if these fish are tank bred.

 

[Jonathan A]

As far as the shop owner knows they were indeed tank bred. Is the shortening of the fin tips a common byproduct of inbreeding or just generally a possible explanation?

 

[Frank Hättich]

As far as the shop owner knows they were indeed tank bred. Is the shortening of the fin tips a common byproduct of inbreeding or just generally a possible explanation?

It's a possible explanation but seen in many line bred strains (also of other species like cacatuoides or macmasteri). Poor water quality can also be a cause of shorter fins.

 

[MacZ]

also of other species like cacatuoides

Interestingly you get two possible outcomes with those. While the caudal fin tends to shorten anyway, the frontal fin rays of the dorsal tend to either be much shorter or much longer than in wild type specimens.

 

[Mike Wise]

Fin shape might be due to age. Alenquer males develop longer fins as they mature. If the male is <2"/5cm SL then it is probably just young. If it is over 2¾"/7cm SL the questions arise.