Guppies in the wild live in northern South America and adjacent islands, including Trinidad, the Netherlands Antilles, the Windward Islands, Barbados, Grenada, the Leeward Islands, Saint Thomas, and Antigua. They also exist naturally in isolated areas as far north as southern Mexico.
In captivity, the various wild populations throughout this natural range have been extensively crossed with one another, resulting in the numerous variations of fancy guppies available as pets today.
Wild guppies are about the same size as fancy guppies, but their coloration varies according to population. Strains of guppies that have been developed in captivity, on the other hand, are extremely varied in their coloration and fin types.
Guppies are small fish, rarely exceeding 2.5″ (6.3 cm) in length. Females are typically larger than males, which tend to be closer to 2″ (5 cm) in length.
Guppies in the wild are much more consistent in coloration than their domestic counterparts. Females are variable in base color, having a gray, greenish-gray, brown, or olive-brown body with a grayish-white belly and nearly colorless fins. Males have a dotted pattern of green, blue, black, red, or yellow. Wild populations also have a peacock’s eye, a colored spot typically located on the upper part of the caudal peduncle (the narrow part of the body where the tail fin attaches) surrounded by a pigmented ring.
Although fancy guppies have a variety of different fin types, the wild guppy has a dorsal fin that’s only slightly drawn out into a pennant, and a caudal (tail) fin that’s normally rounded but may come to a point near the upper section.
Due to selective breeding in captivity over many years, a tremendous variety of guppies is available for purchase in a rainbow of colors and with different fin types. Care requirements are similar among all varieties, so you can purchase whatever type of guppy is available and most aesthetically pleasing to you. The following are some of the different colorations and fin types in fancy guppies:
Albino: Guppies with light coloration and red or pink eyes are referred to as albinos. They come in many types and often are crossed with other strains. (For example, the red albino delta is the result of selective breeding with red delta tails.)
Black: The ideal black guppy has an all-black body with matching caudal and dorsal fins, but not all black guppies fit this description exactly. A black guppy’s head doesn’t have black coloration and can be a number of other colors, although many breeders have attempted to breed completely black guppies.
Blue: Guppies that are predominantly blue in both body and fin color are referred to as blue guppies. As with many types of fancy guppies, there are considerable variations within the blue strain: for example, occasionally a green iridescence shows up in the caudal fins of some blues, making for an even more interesting display of colors.
Bronze: Bronze guppies are mostly gold with at least 25% of their scales darkly edged. The gold doesn’t always extend to the caudal area, which can be a variety of colors.
Delta tail: A delta-tailed guppy has a tail that looks similar to the Greek letter delta (a triangle). Deltas come in many different color strains, including blue, green, purple, and red.
Green: Green guppies are difficult to maintain because of their long, flowing caudal fins. These fins, which can range in color from a mint green to a deep forest green, are beautiful but easily injured due to their large size.
Half-black: The entire back half of this fish’s body is jet black with a hint of blue iridescence. Half-blacks, often considered the most attractive type of guppy, are found in red, blue, purple, and pastel colors.
Multi: Any guppy with three or more colors in its body and fins is considered a multi. Most common in the pet trade are combinations of blue and red, but numbers of yellow-red and green-red specimens have also increased in recent years.
Purple: Purple guppies range in color from pale violet to deep purple, giving them an almost velvety appearance.
Red: Some of the most striking guppies available, reds are generally very hardy fish, making this a good strain for people new to keeping guppies. Some red guppies may appear pink in color, but these are still classified as reds.
Snakeskin: A snakeskin pattern covers at least 60% of this strain’s body. There are two varieties of snakeskin guppies: solid and variegated. Snakeskin solids have a solid color in the caudal and dorsal fin areas, while snakeskin variegated guppies have multicolored fins.
Swordtail: There are three basic types of swordtail guppies: top sword, bottom sword, and double sword. Top swords are closest to swordtailed strains found in the wild and have a pointed extension along the upper part of the caudal fin. Bottom swords have a pointed extension on the bottom part of the fin. Double swords have extensions on both the upper and lower lobes.
Veiltail: Veiltails have lengthened tail fins, with a spread of 45–55°, that droop behind the fish.
Guppies are inquisitive, peaceful fish that can be fascinating to watch. They are very social but don’t necessarily mix well with many other types of fish because of their non-aggressive nature, which makes them likely targets for bullying (or devouring, in the case of larger fish).