Max Size: 7cm

Merry Widow Livebearer (Phallichthys amates)

The Merry Widow is a somewhat rare, peaceful and lively fish perfect for a community aquarium. These fish are very hardy with great personalities, making them ideal for the beginner aquarist. These livebearers know what is happening around their home aquarium and beg for food from their owner while often ignoring other humans approaching the tank.

Ideal tankmates for Merry Widows could include Corydoras Catfish, Plecos, Livebearer and smaller Central American Cichlids. In addition, Barbs, Rainbowfish, Tetras and Gouramis can also make excellent tankmates. However, it would help if you kept in mind that when housing these fish with most of these species, Merry Widows are unlikely to have any fry survive more than a few days, as the other inhabitants will probably consume them.

Merry Widows are best kept in a group of 6 or more individuals, ensuring you have two females to every male, as this will stop any single female from taking the full brunt of the male's continual harassment.

The ideal aquarium setup for these fish would incorporate plenty of hiding places amongst thick planting from both rooted and floating types. Not only will this help your fish feel more secure, but it will also allow them to show their best colours and make your aquarium aesthetically pleasing whilst protecting any fry. The aquarium will need to be somewhat spacious as these are very active fish and will need good filtration.

Merry Widows have a greyish-silver body colour with a bluish sheen. Both the male and female are marked with 6 to 8 dark vertical bars on their body. These fish have a dorsal fin marked with two arcs parallel to the outside edge; both arches are dark, but the inner one is slightly lighter. In addition, they also display a short black line that runs through the eye to the throat, and their gill covers reflect an iridescent bluish-green.


Merry Widow Livebearer
Merry Widow Livebearer
Quick Facts
Scientific NamePhallichthys amates
Year Described1907
Other NamesMerry Widow
OriginsCosta Rica, Guatemala, Honduras, Nicaragua, Panama
Aquarium LevelAll Levels
Best kept asGroups 6+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH6.0 - 8.0
GH5 - 20
KH2 - 6
TDS60 - 150
75 - 80℉
23.9 - 26.7℃

Natural Habitat

Chagres River
Reventazón River
Motagua River


In the home aquarium, the Merry Widow Livebearer will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is relatively simple to differentiate between the male and female Merry Widow. The females are much larger and have slightly duller colouring than the males. In contrast, males have a very long gonopodium that can reach the base of the tail, and they have a smaller, more slender body than females.

Other Livebearers of interest

Cardinal Brachyrhaphis(Brachyrhaphis roseni)
Dusky Millions Fish(Phalloceros caudimaculatus)
Humpbacked Limia(Limia nigrofasciata)
Mollies(Poecilia Sphenops)
Platies(Xiphophorus maculatus, Xiphophorus variatus)
Spotted Skiffia Multipunctata(Skiffia Multipunctata)
View all Livebearers
Date Added: 13/06/2022 10:13:20 - Updated: 13/06/2022 13:18:40