Poecilia sphenops - Black molly

Scientific name: Poecilia sphenops
Common name: Black molly
Group: Livebearers
Habitat: Central America, from Mexico to Columbia
Size: Males:6-7 cm, females:8-9 cm
Biotope: Wild form in fresh and Brackish water, especially in rivers from Venezuela to Mexico.
Social behavior: Peaceful
Diet: Algae, live, worms, crustaceans, insects, insect larvae, plant matter
Breeding: Easy
Tank: Minimum 150 litres
Population: 6-8 fishes for 100 litre
Decoration: Floating plants.
Temperature: 25-28 °C
pH: >7,5
Hardness: >11,2NK°

Description: Elongated, with the males slender and the females with a very round belly profile. Males can reach a length of three inches and the Females almost five.

Several subspecies and color varieties are known. The best known is the "classic" Black Molly where the back is usually Olive Brown and the sides may be silvery with a Green or Blue luster marked with a series of brown or Orange dots. The Popular Lyretail varieties also belong to this species.

An easily cared for fish that does well in all types of community aquaria. Give them a fairly large tank with live plants and open swimming areas, avoid too much driftwood as a rule the livebearers do not like acidic water. Although not a schooling fish they benefit by being kept with a large number of their own kind. Temperature range from sixty-eight to seventy-seven degrees.

As the male matures the Anal fin develops into a structure for reproduction called the Gonopodium. The Gonopodium can be moved in almost any direction and stores the sperm in packs called spermatophores. Once the sperm is inserted into the female it fertilizers her eggs and the rest is stored in the Oviduct walls for later use. The eggs are very rich in yolk and the young develop by consuming their yolk stores. In light colored females pregnancy can be recognized by the growing dark body marking in front of the Anal fin. Young Live-bearers are fairly large at birth and their development is very advanced. They can swim right away, which is needed to avoid their enemies including their parents who give no natal care whatsoever. The fry grow very rapidly and will eagerly accept fine flake food. The number of fry is variable due to the size differences in the species, but in larger females can number well over one hundred.