First: look at the gill plate. A blue acara has a black line below the eye; a JD does not. Both can have bright blue spots on the gill plate but they do differ: a blue acara will typically have 3 bright blue lines going from the mouth up towards the eye; a JD may or may not have bright blue lines, but they are not arranged in this manner.
A blue acara more often exhibits a mid-body blotch. A JD might exhibit a mid-body blotch, but more often it will be obscured by dark coloration, or totally covered by bright blue spots (irridiophores), or not expressed at all.
A JD typically exhibits 2 bars between the eyes; a blue acara only 1 thick bar.
There are many, many differences between the species, though most are rather difficult to describe. Body shape is different; fins are different. Fin trim is different: blue acara typically has light orange to white dorsal fin trim; JD typically bright red dorsal fin trim, though it is not usually as apperant as the dorsaal trim on a blue acara. Different mouths: blue acara has a smaller mouth. Eyes are different: sometimes the bar below the eye on a blue acara can be seen to run right though the eye, though not always.
If the fish are very young and small, not all the traits may be exhibited or be completely apperant. But you generally expect a blue acara to exhibit the bar below the eye, even at a very young age and size...... a JD will never, because it does not pocess this trait.
A blue acara more often exhibits a mid-body blotch. A JD might exhibit a mid-body blotch, but more often it will be obscured by dark coloration, or totally covered by bright blue spots (irridiophores), or not expressed at all.
A JD typically exhibits 2 bars between the eyes; a blue acara only 1 thick bar.
There are many, many differences between the species, though most are rather difficult to describe. Body shape is different; fins are different. Fin trim is different: blue acara typically has light orange to white dorsal fin trim; JD typically bright red dorsal fin trim, though it is not usually as apperant as the dorsaal trim on a blue acara. Different mouths: blue acara has a smaller mouth. Eyes are different: sometimes the bar below the eye on a blue acara can be seen to run right though the eye, though not always.
If the fish are very young and small, not all the traits may be exhibited or be completely apperant. But you generally expect a blue acara to exhibit the bar below the eye, even at a very young age and size...... a JD will never, because it does not pocess this trait.
