The Goodeidae Group. The word "vivus" means "alive" while "parus", with the meaning "bearing", has its origin in the verb "parire", "giving birth". Nowadays, after hundreds of years of draining wetlands and lakes to allow for the enormous expansion of Mexico City, Girardinichthys viviparus can just be found in the remnants of the former huge lakes. It has persisted only in the three artificial lakes in the Parque de Chapultepec inside Mexico City, with a stronghold in the Lago Mayor , with small numbers in the lakes Zumpango and Xochimilco, and in moderate numbers near the airport at Alameda Oriente, which belongs to the former Lake of Texcoco.
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The Goodeidae Group. The word "vivus" means "alive" while "parus", with the meaning "bearing", has its origin in the verb "parire", "giving birth". Nowadays, after hundreds of years of draining wetlands and lakes to allow for the enormous expansion of Mexico City, Girardinichthys viviparus can just be found in the remnants of the former huge lakes.
It has persisted only in the three artificial lakes in the Parque de Chapultepec inside Mexico City, with a stronghold in the Lago Mayor , with small numbers in the lakes Zumpango and Xochimilco, and in moderate numbers near the airport at Alameda Oriente, which belongs to the former Lake of Texcoco. In Miranda et al. This stock is introduced and the species not native to this lake.
No subpopulations are distinguished. The abbreviation for an ESU is composed of the first 3 letters of the genus, followed by the first 2 letters of the species name and an ongoing number in each species. The bold red line encompasses the species' distribution. The drainage of the Valley coupled with the rapid expansion of Mexico City led to a drastic decline in the distribution and abundance of G.
Despite poor environmental conditions, the Xochimilco and Zumpango populations have managed to survive up to the present. This population persists in moderate numbers despite poor water quality, but it is vulnerable to drainage of the lake for maintenance. This species inhabits quiet water of lakes, ponds, canals and ditches over mud substrate.
It prefers clear to murky water and depths between 0. Vegetation is abundant, mainly green algae, Potamogeton , water hyacinths , Lemna and Chara. Studies of Navarrete Salgado et al. This indicates, this species may not be affected so severely by eutrophication of the habitat, which may be the reason it still can be found in the parks' lakes. The pH in the ponds in Chapultepec park was recorded between 7. Probably they start courting with the beginning of the year and the first fry are dropped in February or even January until at least October.
The Mexclapique possesses an uncoiled and short about body length intestine and small pointed teeth, so it is definitely a carnivorous species. The cleft of its mouth is nearly vertical and combined with its preferred habitat at the surface of quiet waterbodies with dense vegetation; it probably feeds from mosquito larvae and small insects falling to the surface. Males are silvery grey, marbled sligthly blackish-grey. During courtship the males become totally blackish to black.
The paired fins are clear. Females are silvery-grey with the upper half of the body darker, the venter brighter. Most females show a gravity spot.
The fins are clear to somehow dusky-greyish. A bluish glimmer can be seen with some specimens. Males and females of the Chapultepec Splitfin are quite easy to distinguish. Additionally, males have also a much bigger and longer Dorsal fin than females.
The difference in colouration is clear and distinct during coutship. Then males have the unpaired fins and the whole body coloured dark uniform black while females stay grey-silvery with a sometimes black belly. During the rest of the time, males have black broad terminal bands on its unpaired fins, mainly Dorsal and Anal fin. Females again have a small recognizable gravity spot in contrast to males. A study from Salgado et al.
Further examinations in these three habitats showed a different abundance and threat of the species. In , Miranda et al. This is a non autochthon population and must go back an introduction by man. A recent finding of a native population was in a small dam near Nopaltepec Lara, However, the species became a rare one in the whole basin.
This translation was published by Theodore Gill in "I send you some viviparous scaly fishes, of which I had formerly given you an account. What I have observed in them this year is - 'If you press the belly with your fingers, you force out the fry before their time, and upon inspecting them through the microscope you may discern the circulation of the blood, such as it is to be when the fish is grown up.
The fins and tail of the males are larger and blacker than those of the females, so that the sex is easily distinguished at first sight. These fish have a singular manner of swimming; the male and the female swim together on two parallel lines, the female always uppermost and the male undermost; they thus always keep at a constant uniform distance from each other, and preserve a perfect parallelism.
The female never makes the least motion, either sideways or towards the bottom, but directly the male does the same. The recommended tank size is at least 80 liters, bigger tanks with a generous base and little height 25cm are enough are better for sure. In aquarium, it feeds also well from flake food, granulate and even tablets, additionally given Nauplia of Brine Shrimps are eaten greedy. The species is not really shy, but likes to use hiding spots to observe the surrounding.
Bring them out in the early afternoon, the time of the day with the highest water temperature. During the warm summer, reproduction will stop and may occur again in fall. Skip to main content. Create new account Request new password. English Name:. Mexican Name:. Original Description:. Drawing of a female Girardinichthys viviparus :.
Girardinichthys is a genus of splitfins that are endemic to Mexico. These highly threatened fish are native to the upper Lerma and Balsas basins, as well as water systems in the Valley of Mexico. Through man-made channels G. There are currently three recognized species in this genus: . From Wikipedia, the free encyclopedia.