Girardinichthys multiradiatus Male

Male Girardinichthys multiradiatus "Maravatio, Mexico" Meek 1904

Common Name: Darkedged Splitfin, Golden Sailfin Goodeid

Synonyms: None

Meaning of Name

Genus- Girardinichthys= Honorific for ichtyologist Charles Girard
Species- multiradiatus = multi = many, radiatus = shiny


Girardinichthys multiradiatus "Maravatio, Mexico"is a livebearing goodeid from the central Mexico. Males of this species have dramatically large dorsal and anal fins which make this fish desirable. Males have an underlying golden base color and dark edges to their fins, hence the common name of "Darkedged Splitfins".

Females are drab by comparison. They have a somewhat washed out golden base color and few if any markings.


This fish is found in quiet, cool and slow moving waters and ditches in the Michoacan and Morelos. Watersheds where this fish are found are typically very shallow and contain many aquatic plants. 

Size, Maturity, and Sexual Dimorphism

Size: Males- 1.75 inches, Females 1.75 inches
Maturity: 1.5 inch
Sexual Dimorphism: Males are more colorful, have exaggerated anal and dorsal fins and an adropodium.


Girardinichthys multiradiatus "Maravatio, Mexico" is not hard to keep provided the aquarist provides clean, cool, neutral to hard water. Temperatures above 72F are detrimental to the health of this fish. Kept at tropical temperatures, it will become listless, stop breeding and may expire. The solution is simple; don't add a heater and keep it in a cool part of the house. 

So, why does this fish need to be kept cool? One location where this fish is found (Lagunas de Zempoala) is at 2800M altitude. Average water temperatures there are 53-64F! I believe this fish evolved to handle cool temperatures.

I performed weekly water changes replacing the tank water with new water that was no more than 72F.


I am not aware of any stomach contents analysis for Girardinichthys multiradiatus . My guess is that it is omnivorous in the wild, pecking and algae and eating any small aquatic fauna it may encounter.


I obtained five young Girardinichthys multiradiatus "Maravatio, Mexico" at the April, 2012 meeting of the Greenwater Aquarium Society (Chicago). Steve Liszt had bred the fish and was offering both the adults and the fry for sale. He had obtained his fish from Pat Hartmann of Detroit, MI. I paid $10 for a bag of five, one inch fry. I took the fish home and placed them in a 10-gallon tank furnished with a sand substrate, java moss and small sponge filter. I also used some floating plastic plant mats.

No heater was used on the tank and water temperatures ranged from around 67F to 72F. The fish grew quickly and by the time the fish were 1.25" long it was possible to distinguish the sexes. Males give very mild chase to other males when sexually mature. Overall, this is a very peaceful fish.

Generally speaking, the highly sexually dimorphic goodeid species exhibit more advanced and dramatic mating displays. This fish doesn't disappoint! Males will flash continuously to attract females, making a showy display. When the fish reached 1.5 inches, I saw my first gravid females. After a gestation of about 6-7 weeks, the females drop four to six, nearly one-half inch long babies.

The babies hid in the floating plastic plants for a week or two before joining their parents in the tank. The parents ignore the babies in the tank, so fry survivability is good. The babies are able to immediately eat finely crushed flake food, but I also feed freshly hatched baby brine shrimp the first few days.


Girardinichthys multiradiatus "Maravatio, Mexico" is a beautiful goodeid that is fun to keep. Other than the challenge of keeping this fish cool, it isn't very difficult and its unique shape and gentle nature should put this fish on your "to do" list.


 Girardinichthys multiradiatus Female