Guppy and Similar Species
Poecilia reticulata
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Open the appSeveral fish can be confused with Guppy. Here are the key differences.
Species often confused with {name}
Endler's Livebearer
Poecilia wingei
Key differences: Endler's Livebearers are generally smaller than guppies (males typically <2.5 cm TL), often have more intense, metallic coloration, and distinct 'Endler's spots' (e.g., black bar, orange patch). While they can hybridize with P. reticulata, pure P. wingei have a more restricted natural range and specific color patterns.
Mosquitofish
Gambusia affinis (Western Mosquitofish) / Gambusia holbrooki (Eastern Mosquitofish)
Key differences: Mosquitofish are typically duller in coloration (grey/olive), lack the elaborate finnage of male guppies, and have a more robust, less compressed body. While also livebearers with a gonopodium in males, their overall morphology and lack of vibrant patterns easily distinguish them from guppies. Mosquitofish are also generally more aggressive.
Molly
Poecilia sphenops (Short-finned Molly), Poecilia latipinna (Sailfin Molly), Poecilia velifera (Giant Sailfin Molly)
Key differences: Mollies are generally larger and more robust than guppies, with a deeper body. While also livebearers and belonging to the same genus, they typically have larger dorsal fins (especially sailfin varieties) and different body shapes. Their coloration, while variable, does not usually exhibit the intricate patterns seen in fancy guppy strains.
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