Petenia splendida

Xanthi tables, red morph

Petenia splendida is a cichlid from Central America, which can reach up to half a meter in total length (weight to three kilograms, females remain slightly smaller). He stands in the New World subfamily Cichlinae ( Tribus Heroini ). Until some years ago, he was at best at the local population ( already among the Maya ) as a good food fish ( in Mexico and Guatemala say this Cichlidae " Tenguajaqua " or " Tenguayaca " ) of interest. In the English -speaking world it carries in allusion to his head form the name " Bay Snook " ( " snook " means " long nose "). The German name " Spotted predatory cichlid " is totally uncharacteristic, even misleading, for this ambush predator. The genus is monotypic Petenia.

Features

Specific type is the stretched and laterally strongly compressed body. The base color is shiny silvery (Latin splendidus " shiny ") with a series of dark spots of various sizes along the body sides and irregularly scattered on smaller scales and fins. Some stains can be bright margins, the ocelli on the caudal fin base ( one on each side of the body ) always are. The gill cover wear at eye level usually also a round spot. Up to six major edge spots stretch depending on mood from vertical to bind. Already since 1935, the natural occurrence of a xanthi matic color morph is known, the drawing shows no features, but a relatively uniform, reddish ground color ..

The unpaired fins often show a yellow or reddish tinge. The caudal fin is rounded, their posterior margin sometimes truncated obliquely, so that the dorsal part is larger than the ventral.

Fins formula: D XV/13-16, A V-VII/8-11, P 15, C 17, approximately 42 scales along the lateral line. Scaly cheeks -. (2n =) 48 chromosomes.

The mouth is large; foot column extends to below the eye. If the fish but his mouth unlocks, it is pre-stretched " huge " and tubular far. From the look- out position it is pushed in seconds in a flash of forward movement of the prey, mostly smaller fish. If the prey is larger and can not be fully accommodated in the tube it, it is held in place by striking elongated maxillary teeth.

Similar to Epibulus insidiator of sliding on the skull top extension of the premaxilla is very long. It reaches its mouth closed almost to the occipital crest. But the lower jaw itself is advanced because the jockstrap from soft, thin cartilage zone is very mobile in itself. The feeding is done by cranial elevation and hyoid depression with a dead - overcoming. The Branchiostegalmembran ( usually with five radii ) is of small size. The measures clapped, thin-skinned mouth tube measures 60 percent of head length; its diameter is at the head of about 40 percent, which exceeds the width of the fish body. A similar mechanism, only slightly less pronounced, showing the related genus Caquetaia with several Central and South American species. Similarly, the labyrinth fish catches Luciocephalus pulcher its prey. Such a folded " trunk " can not be fully straightened. The main food of it highly specialized Petania splendida are fish and crustaceans. However, it can take on other Nährtiere also to and from the ground, for which he unicuspid, enlarged and curved " dog teeth " features. The gills Reuse consists of only a few short and wide projections on the four gill slits - an indication that jockstrap and gill covers are not strongly splayed. The trunk is also often pre-stretched without food: the " yawn " to impress within species and the very restrained mouth tugging under the Kommentverhaltens.

Behavior

From aquarium is the fish, an eye-catcher thanks to his mouth tube, praised for its peacefulness and tolerance. Although it occurs in open water (over mud, gravel and Grus, it needs no vegetation to hide or spawn, but it uses like to lurk ), he also holds in smaller basins well and can be used to feed even art. Sometimes he lives individually, but mated more frequently or in smaller (or larger ) groups. Sexual maturity occurs at about 15 cm in length. Spawning Prepare couples ( who can stay together even alleged lifelong) show only a inconspicuous courtship with mutual Anfächeln. The eggs (several hundred eggs of 1.8 mm longitudinal diameter ) is simply placed on blocks or logs that have been previously cleaned something, and common guarded ( free spawning). The larvae hatch after about 72 hours and free swimming after another 96.

Dissemination

In larger rivers (eg Rio Usumacinta ) and lakes of the eastern slope, d (it was described from the Petén ) in parts of Chiapas, in Quintana Roo, Tabasco and Yucatan ( Mexico), Guatemala and Belize - there usually from hard water at pH 6.8 to: h to the Atlantic Ocean, the northern Central America 7.8; Water temperature 26-28 ° C. He comes about by flooding, even in small standing waters, even up near the coast and there also in brackish cenotes. For human consumption Petenia splendida was frequently exposed or grown in fish farms. Thus, the original distribution can no longer accurately represent.

As part of the global " Tilapia projects" WHO also a native of North Africa and the Middle East blue tilapia Oreochromis aureus was exposed in Central America in addition to also native to Central America Großcichlidenart Parachromis managuensis. Due to their enormous adaptability, the tilapia are spreading very successful and displace ancestral species, including Petenia splendida.