u/Shemar_Livebearers

Used to be located in a small section of the San Juan River system, Mexico. Couchianus is part of the Northern platyfish species group, being close relatives to Xiphophorus gordani, and Xiphophorus meyeri. Males gets to around 1.5 inches and females around 2.3 inches in size. They are moderately robust, olive gray in color, with some specimens having black blotches on them. This species is currently extinct in the wild according to the IUCN, due to invasive species and habitat destruction. There’s still specimens being kept in the hobby, by serious hobbyist and organizations like the ALA (American Livebearers Association), XWG (Xiphophorus Working Group), and XGSC (Xiphophorus Genetic Stock Center) at Texas University.

Picture credits: Wikipedia (1), Nilsson, K. (2), Joel Sartore (3)

Located in Jamaica. Male gets around 1.3-1.5 inches, and females 2 inches in size. A small sized Limia species. Like in the common name males has black pigments on the under side of its body, as for females they have a very opened gravid area that’s black when holding fry. Not much to say on them but the pics says it all.

Picture credits: Kjell Fohrman (1), Radek Sejkora (2), Fishpedia (3), Aquarium Glaser (4), Jon Sandford (5)

Located in lake Miragoane, southwestern Haiti. Males gets to around 1.5 inches and females around 1.7 inches. They share waters with other livebearer species like, Limia (nigrofasciata, garnieri, mandibularis, immaculata, miragoanensis, islai), and Gambusia beebei to name a few. Appearance wise it’s easily mistaken for Limia vittata, but both species comes from two different countries as in Vittata is only found in Cuba. They are both slightly robust, with yellowish olive gray bodies. And black and orange melanistic patches all over them.

Picture credits: Ch. & M. P. Piednoir

Located in Rio Los Espinos, Izabal basin, Guatemala. They’re part of the mexicana complex. Males gets to around 2.5-3 inches and females as well. They are moderately robust, with small heads. large tail fins, males have a nice wide dorsal with black pigments, rows of lateral dots, and a nice blue iridescent sheen to them.

Picture credits: unknown

Located in Costa Rica and Nicaragua. Males gets to around 1.5 inches and females around 2 inches in size. They are slender specimens with orange gray hue body, black dorsals with translucent orange in the center. The males gonopodium are fixed off centered on the body, and it has a hook at the end, to keep it inside the females when mating. And yes as the scientific name literally means Strange Hooked P*nis. I find it funny every time lol.

Picture credits: Aquarium Glaser

Located in southern U.S (South Carolina, Georgia, Florida, & Louisiana), they are the smallest Livebearers in North America, with males reaching 0.8 inch in size, and females 1.2 inches in size. Weirdly enough, this species has one of the highest body size to gonopodium length ratio. They are olive gray in color with black vertical lines going across the body, and a black dorsal speck.

Picture credits: Isaac Szabo (1), Sam Borstein (2), The Fishes of North Carolina (3), Florida Museum of Natural History (4), “Fry” Thomas Gleim (5), “Gold/Yellow Leusistic” Sam Borstein (6), “White Leusistic” Unknown (7)

Located in Cricamola River, Panama. They’re named after the river where they’re mostly found. Males reaches around 1.2 inches and females 2 inches in size. They are olive gray in color, slender body, blue eyes, with yellow around the iris, yellow fins, and having a faded reticulation between the scales. Not as attractive as other members in the genus, but being simple they still look amazing.

Picture credits: Samuel Valdes

Located in Ilopango Lake basin, El Salvador. Males gets to around 2.25-2.5 inches and females around that same size as well. They’re part of the Sphenops complex being close relative to P. sphenops, P. chica, and P. catemaconis. They are olive gray, robust shape with short thick penduncles, angular sphenops like faces, rows of lateral spots, a nice blue metallic sheen to them and a blotched on the tail base. A beautiful molly species.

Picture credits: Manfred K. Meyer

Located in Cuba. They are a bigger species of gambusia with males reaching around 1.5-2 inches and females 2.5-3 inches in size. They are robust, both sexes have blue gem colored eyes, yellow-gray bodies, and spotted lateral lines. Unlike most other Gambusia species, this species is pretty docile. Also they are a sister species to Gambusia rhizophorae.

Picture credits: Matt Ford (1&2), Goliad Farms (3), Thomas Gleim (

LOTD: Poecilia (Allopoecilia) dauli - Mirina Molly
Located in Venezuela. Males gets around 1.2 inches and females 2 inches in size. A small sized Molly species. They’re also a sister species to Poecilia caucana, sharing the subgenus of “Allopoecilia”, and look identical in appearance. With their gray slender bodies, blue iridescence, black and yellow dorsals, transparent orange-yellow tail fins, and thick penduncles.

Picture credits: Rene Velagyi

Located in Mexico all the way to Panama. Size wise males gets around 1.5-2.5 inches and females 3 inches in length. They are part of the mexicana complex. They are gray in color, with a long body, but short penduncle, vibrant iridescent blue, orange sheen, and thick orange band on the tail fin. Very glittery livebearer. The pics doesn’t really do them Justice, unfortunately.

Picture credits: Aquarium Glaser (1-3), Heiko Bleher (4), conobio-pj010 (5), “Melanistic” - AdrianHD (6&7)

Located in the Dominican Republic. Males reaches 1.3 inches and females 1.8 inches in size. They are slender, an olive gray/cream body, and with an orange dorsal. Plain looking species compare to other limia species.

Picture credits: Dan Fromm (1&2), : Rodet Rodriguez (3)

Located in Andros Island, Abaco, Bahamas. Sister species to Gambusia manni. Also close relative to G. nicaraguensis. Hubbsi (males) evolved to have longer, bony gonopodium tips, because of the presence of predators, they mate via forceful thrusting instead of courting. Males gets to around 1.3 inches, and females around 2 inches in size. Appearance wise they are identical to Gambusia manni, with their olive gray bodies, short yellow dorsals, black vertical streak going across the eyes, tiny row of pigment spots on the fins, but unlike Manni which has short gonopodiums, they sport a longer gonopodium.

Picture credits: Marcio Silva Araujo

Located in Mexico. Males gets to around an inch, and females 1.5 inches in size. They look identical to Heterophallus rachovii. With a slender cream-gray body color and sparkling iridescent scales. This species and others in the Heterophallus genus was once part under Gambusia hence why their common name has Gambusia in it. Heterophallus is a sister genus to Gambusia.

Picture credits: U. Dost (1), Manfred K. Meyer (2)

Located in Rio Catu in Alagoinhas, Baia, Brazil. Males gets to around an inch, and females around 1.4 inches in size. They are olive gray in color, with small pointed faces, vertical bars running across the body, and males sporting long gonopodiums. An unusual and rare type of Livebearer species.

Picture credits: J. C. Merino

Located in Cuatro Ciénegas, Mexico. They’re an endangered species of Gambusia, and locally go by the name of “Guayacon de Cuatro Cienegas”. Males gets to around 1.2 inches and females around 1.6 inches in size. They are olive gray in color, with blue iridescent slender bodies, and sporting a thick horizontal band going across. A pretty Gambusia species.

Picture credits: Andreas Tveteraas (1), J. C. Merino (2&3), Manfred K. Meyer (4&5)

Located in Mexico (and every type of aquarium lol). Males range from 2-3 inches and females 2.5-4 inches in length. They are part of the Sphenops Shortfin complex (tricuspid tooth bone). Closest relatives being Poecilia catemaconis, Poecilia chica and Poecilia marcellinoi being the sister species. Like with other Sphenops complex species they have a bone in their mouth that’s trident shaped which separates them from the Mexicana Shortfin complex which has a unicuspid bone. Wild type version of this Molly is not as appreciated or common compared to the domestic strains in the hobby. To think they all came from this Molly species, and hybridized with other Molly species. Sphenops have a wide range of phenotypes based on locality. They have a slender to robust body shape, olive grey body color. Some specimens can be mottled/Dalmatian/freckled/few spots/none at all, very iridescent etc. They have short dorsals and small size tail fin that can have orange trims and black to it.

Picture credits: Michi Tobler (1-3), sggs (4), joshy98 (5), Jireh Rojas (6&7), Quetzal Angeles (8&9), “Feral - Florida, USA” James Lafo (10), “Feral - Dominican Republic” Mark Genry Sabaj (11), “Feral - San Fabian, Philippines" Andre Tila (12)

Located in Jamaica, they’re stay in freshwater, and occasionally brackish. They get to around 1.7 inches for males and females 2.5 inches in length, and have a nice slender body, olive in color, with a faint brown strips going from head to tail.

Picture credits: Smithsonian Tropical Research Institute (1), J. C. Merino (2&3), E. Schraml (4), E. Pürzl (5)

Located in lower Uruguay River in Uruguay (Río Negro and Salto Departments) and Argentina (Entre Ríos Province). Males gets to around 0.85-0.9 of an inch and females around 1-1.2 inches in size. They are a recently discovered species of Phalloceros, which they are part of the Phalloceros harpagos species complex. They are olive grey slender body fish, with rows of bars / an ovalish spot (on females), and males sporting long gonopodiums.

Picture credits: SERRA, Wilson s.

Located in Rio Nava, Coahuila, Mexico. A close relative to Gambusia clarkhubbsi. They’re named in honor of Louis A. Krumholz, for his contribution to aquatic biology. Males gets to around 1.5 inches, and females 2.4 inches in size. They are olive gray, slender bodied specimens, with black and yellow-orange trimmed dorsals, yellow-orange tailfin, silver iridescent sheen to them, and black reticulation between the scales.

Picture credits: E. Pürzl (1), J. C. Merino (2), H. J. Mayland (3&4)