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Re: Romer's book


I am not so sure that A. sp. Bluehead/Steel-blue is a pure species. Many Apistogramma specialists
in Europe, North America, & Japan believe it is a cross between 2 closely related species. There is
little doubt that the fish from Europe are crosses! Here is a little history on this fish.

This fish first appeared in 1994-5 in Japan & Europe from Singapore. In Japan it was immediately
recognized that it was not exactly a form of the caetei- nor resticulosa-complex. Matzusaka
published the first photos of this fish in his book under the name 'New Blue' & considered it a
domestic cross between A. caetei x A. resticulosa. Bork, who considers it a form of A. caetei
writes that a German breeder was able to build up a new breeding line of Bluehead (Blaukopf) using
"a few Asian males and some wild females". The question needs to be asked: If we do not know where
this fish originates, how can we be sure that the "wild females" are the same species??? Obviously
we cannot - and most likely are not! Römer considered it to be a "part of the resticulosa-complex"
when he wrote this part of his atlas (1996!). Koslowski hedges his bet by stating (translation),
"The Bluehead Apistogramma (= A. sp. Steel-blue) probably is a hybrid product between a form of the
A. resticulosa- and one from the A. caetei-complex".

These are all opinions, of course, & we cannot be certain which opinion is correct. But let's look
at what we know about hybridized apistos. Most hybrid apistos, like A. sp. Orange-fin & early
accidental crosses of A. sp. Tefé & A. agassizii, show irregular rows of scales, especially in the
caudal peduncle area. The dark markings often are irregular & not the same on fish from the same
brood. Fertility & viability usually are low, too. This is true of most - but not all - crosses.
Koslowski wrote about a domestic cross between A. sp. Tucuruí & A. geisleri. Although the 2 species
are both members of the regani-group, they are from different species-complexes within the group.
Koslowski wrote (translation), "Some droppeddue to deformed scales and fins. Others grew to a size
which in many Apistogrmma would be sexually mature. Astonishingly it was only males that reached
this size ...". Does this sound familiar??

We can look at the diagnostic features of the Bluehead. These features may give some indication
from which 1 or 2 species the Bluehead originated.

Body shape: Moderately robust (all but 1 caetei- & only a few resticulosa-complex forms)
Size: Moderately small (resticulosa-complex)
Lateral band: Narrow (resticulosa), slightly zigzag (caetei), ends in Bar 6 ( like in A. sp.
Cheek-spots (Wangenflecken) - a member of the resticulosa-complex), without a right angle break
Caudal fin: Round (caetei & resticulosa) with prominent bands of spots (caetei)
Abdominal streaks: broader than on resticulosa-complex forms; present mostly in front of the anal
fin when visible (caetei)