15 Fin-tastic Facts About The Green Swordtail For Kids

Green Swordtail facts about the fish that is primarily found in rivers, ponds, and streams from Mexico to Northwestern Honduras.

If you're looking for a lovely fish in your aquarium, take a look at the most popular Green swordtail fish (Xiphophorus hellerii) with distinct fins that come in a wide range of colors. Its scientific name comes from Karl Bartholomaeus Heller, an Austrian botanist, and naturalist who collected their specimens. Their popularity comes as they are peaceful and easy to look after them, even for beginners. The Green swordtail was bred into several hybrid forms for the aquarium hobby and got variations in colors and color mixtures. These colors include red, green, black, and albino. These fishes that belong to the Poeciliidae family are livebearers, like Mollies, Guppies, and Platy fish who give birth to live, free-swimming young ones. Swordtail fish are open to a wide range of foods. In their natural habitat, they consume a lot of algae and other vegetation. Since they will eat almost anything, you can feed them quality flake food or live foods such as small crustaceans, insects, and annelid worms.

Don't limit yourself here. Check out our other articles such as sockeye salmon facts and sardine facts for more interesting articles.

Green Swordtail

Fact File

What do they prey on?

Small crustaceans, insects, annelid worms and plants

What do they eat?


Average litter size?


How much do they weigh?


How long are they?

5.5-6.3 in (14-16 cm)

How tall are they?


What do they look like?

Olive green

Skin Type


What are their main threats?


What is their conservation status?

Least Concern

Where you'll find them

Rivers, ponds, streams, and warm springs


North America and Central America, Mexico





Scientific Name

Xiphophorus hellerii





Green Swordtail Interesting Facts

What type of animal is Green Swordtail?

The Green swordtail (Xiphophorus hellerii ) are the most popular freshwater fishes.

What class of animal does Green Swordtail belong to?

The Green swordtail (Xiphophorus hellerii) belongs to the class Actinopterygii. These are also known as ray-finned fishes, a clade of bony fishes. Ray-finned fishes get their name from their fins, which are webs of skin supported by bony or firm spines called rays.

How many Green Swordtails are there in the world?

The Green swordtail (Xiphophorus hellerii) is one of the world's most recognizable aquarium fishes and is widely used in the ornamental trade. Hence, the population must be more numerous to list.

Where does Green Swordtail live?

If you want to catch them in the wild, these Green swordtails (Xiphophorus hellerii) can be found in fast-flowing freshwaters like densely vegetated rivers and streams, as well as warm springs, ponds, and canals. They are usually found at depths up to 5 ft (1.5 m) at the height of 4,920 ft (1,500 m) with a water temperature ranging between 65-82°F (18-28°C).

What is a Green Swordtail's habitat?

The Green Swordtail (Xiphophorus hellerii) is inherent to freshwater systems in Mexico and can be found throughout North and Central America, from Veracruz, Mexico, to Northwestern Honduras. It has spread to other river basins in Mexico and worldwide, and it can now be found on all major continents except Antarctica.

Who does Green Swordtail live with?

The Green swordtail (Xiphophorus hellerii) is generally a calm, energetic fish that swims in large schools. This fish is friendly with most other good-natured fish its size. Apart from individual fish being peaceful and harmonious, some older male fishes can be aggressive toward each other and other species. Fishes like Platy fish, mollies, Armoured Catfish, Angelfish, and Plecostomus, and larger Characins like the Black Skirt, Red Serpae, and Silver Tip make excellent tankmates.

How long does Green Swordtail live?

If you take good care of these Green swordtail (Xiphophorus hellerii) fishes, they can survive from three to five years in your aquarium as well as in the wild.

How do they reproduce?

Green swordtail (Xiphophorus hellerii) fishes are livebearers and give birth to young ones after eggs in the female fish form by mating with male fish. While they usually mature for about 8-12 months, it is observed that they begin breeding when they are younger than three months. When a female is pregnant, you will notice a gravid spot which is a dark mark situated just behind the anal fin. After the gestation period of 24-30 days, a female fish can give birth to 20-100 fries, but the average is around 80. It is essential to isolate with a breeding trap or give enough hiding spaces, such as densely rooted or floating plants; otherwise, swordtails will chase their fry and may eat them if got a chance.

What is their conservation status?

The Green swordtail (Xiphophorus hellerii) fish is among the most commonly available tropical fish. As per IUCN Red List Status, it is listed as Least Concern.

Green Swordtail Fun Facts

What does Green Swordtail look like?

Coming to its physical description, the Green swordtail (Xiphophorus hellerii) has an olive green body with red or brown lateral stripes along the body and speckles on the dorsal fins and occasionally on the caudal fins. The male fish has a sword-like caudal fin, yellow in color with a black edge on the bottom. Captive breeding has resulted in plenty of color variations and patterns for the aquarium hobby.

The Green Swordtail is frequently observed swimming and feeding in your aquariums at a moderate temperature.

How cute are they?

These fishes are pretty to watch with unique fins and a wide range of colors. Indeed, the beautiful swordtail of male fishes is one of the most eye-catching physical characteristics in community aquariums.

How do they communicate?

Studies show that fishes usually communicate through changes in the chemicals in the environment. You will be surprised to know that swordfish use chemical cues in the urine as their mating signals.

How big a Green Swordtail can get?

A male Green swordtail (Xiphophorus hellerii) can grow up to a maximum length of 5.5 in (14 cm), and a female can grow up to 6.3 in (16 cm). These fishes can be purchased in stores at a length of 1-2 in, in most cases.

How fast can a Green Swordtail swim?

The precise swimming speed of the Green swordtail (Xiphophorus hellerii) has yet to be determined. While it has been observed that male fish carrying a long sword will acquire drag and thus weaken the swim.

How much does a Green Swordtail weigh?

The exact weight of the Green swordtail (Xiphophorus hellerii) is unknown. But is likely that they won't weigh more than a few pounds owing to their small size.

What are the male and female names of the species?

The male and female do not have separate names. You can, however, easily distinguish between a male and female swordtail species. As male swordtail fish are often aggressive towards other males of the same species, you should keep only one male with three to four females in your aquarium. So the probability of getting a female fish is more. Moreover, female bodies are rounded, are longer than males, and have rounded tail fins compared to males who have the tail-fin extension.

What would you call a baby Green Swordtail?

Green swordtails are livebearers and give birth to young ones called fry. The fry will become a juvenile in four to six weeks.

Do humans eat them?

These Green swordtails are not yet included in the human food diet.

Are they dangerous?

Although the Green swordtail is an active and peaceful member of the community aquarium and is considered not dangerous, male fishes may sometimes exhibit territorial aggression.

Would they make a good pet?

These Green swordtails get along well with most other good-natured fish its size. They can make excellent tankmates with Angelfish, Platy fish, Armoured catfish, Mollies and Plecostomus, and larger Characins like the Red Serpae, Black Skirt, and Silver Tip. Remember, it is important to have plants and other structures in the aquarium that will provide a safe place for the fry. It is essential because other aquarium inmates will eat newborn fry if they cannot find shelter.

Did you know...

The surprising fact of Green swordtail fishes is that a female fish may occasionally change sex and develop a sword on her tail, mainly if she is old or infected with parasites.

Green Swordtail vs Anchovy

An anchovy is a small, popular forage fish, while Green swordtails are ornamental fish. Anchovies can be found in marine and brackish water, whereas Green swordtails are freshwater species. Anchovies are a part of regular human food and are used as fish bait, while Green swordfish are not.

Why does the Green Swordtail name include a sword?

It got its name as the male's caudal fin (tail fin) has an elongated lower lobe that looks like a sword.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish from our white tuna facts and warmouth fun facts pages.

You can even occupy yourself at home by coloring in one of our free printable green swordtail coloring pages.



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