Butterfly splitfin-Ameca splendens

BUTTERFLY SPLITFIN
Also: Butterfly goodeid.

Origins:Central America, in the Rio Ameca and the Rio Teuchitlan in Jalisco State, Mexico.
Size:4 & 1/2 in.
Diet:Prepared foods, plant matters, and small livefoods.
Water:Temperature 68-84F; hard (100-150 mg/l), and neutral (pH 7.0).
Temperament:Males are territorial and aggressive.

These livebeares can be sexed not only by their size but also by their coloration. The larger female has an irregular pattern of dark spots over her body. In the more plainly colored male, the caudal fin is edged with black and then yellow, and the dorsal fin is more prominent. Females give birth to offspring that have an attachment resembling an umbilical cord; this disappears soon after birth. A typical brood consists of about 30 young, born about two months after mating. Young females giving birth for the first time have only a small number of offspring, which may vary noticeably in size. These goodeids require a well-lit tank with plenty of retreats, and they will browse readily on algae growing in their quarters.

 

Additional Information from Aquarium Fish International:

Livebearing fish that spawns in pairs. Female drops are usually 10-15 fry at a time, however larger females can release up to 30 fry. Out of the livebeares, the butterfly goodeid is less likely to eat their own fry (mainly due to the larger size which is about 1/2").
A minimum of a 29g aquarium is the suggested size for a small colony and a power filter is recommended since this type of fish likes water movement.

Diet: in addition to what has been suggested above...Baby Brine Shrimp/small crustaceans, Veggies, and Meaty Foods, Live worms and even frozen bloodworms.
Water: Temperature MORE THAN 80F

 

How to tell the sexes apart and pertinent breeding information

Males have an andropodium (modified notched anal fin).
It is not an intromittent structure like the gonopodium of Poeciliids, but rather it is a grasping structure used to simply hold on to the female's anal fin. The first few rays of the andropodium are modified with small hooks that simplify this task.

The male actually has a soft, fleshy organ called a pseudopenis that is inserted into the female's vent while he holds her with the andropodium. Mating only takes a few seconds and can occur as early as 6 months of age.

Babies develop within the female's body and are attached to the uterine wall via a trophotaenia (umbilical cordlike structure). Young are born about 56-60 days after fertilization and often still have the trophotaenia attached to them for about a day or so until it falls off on its own.

Females DO NOT store sperm and must mate re-mate to have additional fry. Females are known to drop several times, and then go for periods of several months without even a single drop...which is usually in the summer.