update!
I now have 2 breeding pairs for a while now (I picked up another wildcaught pair from the same shipment), and I have the first offspring of that pair; tiny <1cm black 'tadpoles'.
already eating artemia, crumbled flake and the occasional cyclops.
New data:
L brevispinis is DEFINITELY NOT a mouthbreeding fish!
why? because they glue the young to the back of the cave, exactly like many substrate-breeding cichlids do.
The first time I found out about this, was when I tried to empty the pipe-cave in wich pair #1 currently is breeding. the adults dropped in the jar alright, but the young didn't.
these youngsters were already 10 days old or so, and coloring (the eggs are white, so are hatchlings); but they are glued in a small pile to the back of the pipe and not even emptying the pipe above the water couldn't dislodge them....
tough little critters! refilled the pipe, put dad in too (mom escaped the manouvre) and he's right back into blocking the pipe.
No mouthbrooder would want sticky eggs or fry; he would choke to death on it; as an unwritten 'rule', mouthreeding fish have non-sticky eggs and fry.
another test with the other pair gave exactly the same result.
The breeding care is very good; once reunited with their own fry, they more often than not pick up right where they left (not always; I wasted a few nests
)
If L cyclurus has the same behaviour is to be seen; mine aren't breeding yet.