Serrasalmus geryi
Serrasalmus geryi was first described by Jégu and Dos Santos in 1988. The scientific article in which the species was first described is “Le genre Serrasalmus (Pisces, Serrasalmidae) dans le bas Tocantins (Brésil, Parà), avec la description d’une espèce nouvelle, S. geryi, du bassin Araguaia-Tocantins”. They are part of the Piranha family (Serrasalmidae). The English name for this fish species is Gery’s Piranha or Violet-lined Piranha.
De geslachtsnaam Serrasalmus is afgeleid van het Latijnse “serra” (zaag) en “salmo” (zalm), verwijzend naar de zaagachtige tanden en de algemene vorm die lijkt op die van een zalm. De soortnaam geryi is een eerbetoon aan de Franse arts en ichtyoloog Jacques Géry (1917-2007).
Description
Serrasalmus geryi can reach a total length of over 30 centimeters. In an home aquarium they seldom grow to be over 25 centimeters.
Geryi’s Piranha has a brightly shining silver coloured body. The coloration turns darker towards the upper body.
The most striking external feature, however, is without a doubt the dark purple stripe, which runs from under the chin over the head to the base of the tail. When the fish is viewed from the side this stripe is not visible, but as the fish turns a little it gradually becomes more visible. The usefulness of this line is unknown.
The pectoral and side fins are colorless to transparent light gray. All other fins are grayish in color. The tail is dark, with a light vertical band down the middle. The eyes are reddish.
Aberrant/unique Appearances:
– Dark purple stripe running from below the head, across the head, to the base of the caudal fin.
– Side compressed body.
– Shoulder patch.
– Orange to red eyes.
Diet
Fish (fillets, frozen fish such as smelt, live*), shrimps, mussels, earthworms and mealworms, insects, pellets.
* If live fish are fed, a number of things must be taken into account: firstly, all fish can introduce diseases and/or parasites into the aquarium, including goldfish, ide, and other commonly used cold-water fish, as well as tropical fish. It is therefore advisable to keep feed fish in a quarantine aquarium for a week or two first, in order to ‘fish out’ the sick and weakened specimens. In addition, it is important to bear in mind that goldfish and their close relatives are not particularly nutritious. A diet that consists mainly of live fish is therefore not recommended. This is especially true because goldfish and other Cyprinidae (carp-like fish) contain hormones—known as “thiaminase/vitamin B1 inhibitors”—that inhibit the production of certain growth-stimulating substances in predatory fish. A very one-sided goldfish diet can therefore lead to growth and development disorders!
It may take a while for the fish to accept prepared food: if this is the case, make sure the fish is well fed with live food and then introduce a fasting period of a week to 12 days. During this period, provide the desired prepared food while the lighting is dimmed or turned off. If it doesn’t work the first time, supplement with live food and try again. Piranhas can go without food for a number of weeks without any problems, so the fish is not in any danger during this “cure” (with the exception of specimens smaller than about 8 centimeters!).
The Aquarium
Young and semi-mature animals can be temporarily kept in an aquarium of 80x35cm. but for fully grown specimens at least an aquarium of 120x45cm. is required. If kept in a group of 3 specimens the aquarium should be at least of 150x50cm. in size. Each additional fish requires an additional 150 liters, with length and depth being more important than height.
Compatible Species
Geryi’s Piranha is one of the rare Serrasalmus species that can be kept (reasonably) successfully in a group, provided the aquarium is spacious enough for each fish to claim a territory, and is provided with a large number of hiding places. Nevertheless, it is advisable to keep this species solitary: they will always remain fin-biters, with an aggressive and unpredictable character. Keeping this species in a school is only advisable to experienced piranha keepers!
With sufficient hiding places, a catfish, such as a Pleco or a Thorny Catfish, can be placed to take care of any food scraps, but there is no guarantee that this will go well. Other fish are unsuitable to keep with this species.
Comments
This species is rarely found in private aquariums, mainly due to the fact that they are only found in a single river. For this reason, few fish are exported and very high prices have to be paid for them.
Video
Author
Jonas Hansel – Piranha-info.com (original website no longer online)
Copyright images
