Cüce Amerikan Dünyası

Today i introduce another species of the Dicrossus family.
Before i introduced the most common of this genus, the D.filamentosus, and now the second most known one, the D.maculatus(Steindacher, 1875).
This species lives in the lower area's of the Rio Tapajós, and in some clearwaterhabitats in the area where the Maues-Acu and Aripua stream into the Rio Solimoes.
There were more area's mentioned in the past, but the fish that were found there, were most probably Crenicara puntulatum, from the genus in which the "checkerboards" were placed in the first place before.
Another synonym for this fish is Crenicara praetoriusi(Praetorius, 1935).
Ladiges mentioned the import in Hamburg, Germany already in 1951, but they came in very scarce, and finally in 1987 A.Werner managed to import bigger numbers from a very clear shorelake of the Rio Tapajós, about 20-30 km from Santarem.
Important might be, that Heiko Bleher(also a member here) already mentioned in 1989 that he had imported thousands of them back in 1975, but that they lost the competition with the more populair D.filamentosus.
Maybe Heiko can shead a light on this matter.

In compare to D.filamentosus, which has the outher spines of their tailfin grown out to 2 long filaments(males), D.maculatus has a more spade-formed caudalfin, in which the middle spines can outgrow in the middle sometimes.
I think this species is more colourfull overall then D.filamentosus, which has more shiny scales for that.
Males can outgrow up to 10 cm(4 inches), females mostly not bigger then 6 cm(2,5 inches).
They like to glide near the bottom to search for food, and meanwhile vibrate very fast with their pectoral and pelvic fins, to disturb the substrate.
They feed mainly on insectlarve and little crustations.

These waters in their habitat are mostly very clear, not very deep, under 1 meter mostly, temperatures between 27-35 degrees Celsius, pH around 4.8-5.4, DGH lower then 1.
But there is a difference in the different seasons of course, when the waters rise.
But they will be found mostly in the shallow parts of those waters.
The bottom of these shallow waters are full of organic debree and leafs, like we see with Apistogramma also.
When they are searching for food, they like to do this in small groups from 6-12 animals.
They even pick some leafs with their mouths, and turn them around to see if there is something to eat on the other side of this leaf.

Like D.filamentosus, the females like to lay their eggs on the leafs of plants, and later on lead the brood over the top of the mostly abundant waterplants to find food.
It seems that they like to breed in colonies also.
Like in D.filamentosus also, the females of this species develope red pelvic fins when breeding, sometimes even yellow.
The female tends to have the dominant rol in the mating first, and when she has lured the male in, he will court her in his most beautifull colours.
After the mating she will chase of the male, and she takes care of the brood alone.
It will last about 10-11 days to hatch for the fry after the mating, at higher temperatures(27 degrees Celsius up).
They like to lay their egss on vertical standing leaves, but sometimes they breed in caves also, but lay the eggs on the bottom, not on the ceiling of the cave.
The fry is so small that they can't manage to eat the larve of brine shrimps in the first days, so they need smaller food then.
A brood can be up to 70-100 individuals!
As in Apistogramma, just a lesser males will be in the brood, when the pH is low.
Mayland and Bork(2001) also mentioned the temperature could be responcible for this fact, and we know this from some Apistogramma species also.
They said at temperatures from 30 degrees up, the fry is 50/50 in gender.