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Perca fluviatilis

Foto: Pietro Ceccuzzi (from NCBI)

Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Superclass: -- bony , : spiny rayed fishes Subclass: -- neopterygians Infraclass: Teleostei Superorder: Order: Suborder: Percoidei Family: Percidae Genus: Perca Linnaeus, 1758 -- yellow : Perca fluviatilis Linnaeus, 1758 Morphological features Max. length: 51.0 cm; Max. weight: 4,5 g; Max. reported age: 22 . Morphology: Greenish-yellow body with scales, with 5-9 darker transversal bands on sides. Rayed spines: 14-20 dorsal, with 13-16 soft rays; 7-10 anal soft rays. The first is gray and greater, second dorsal and pectoral yellow, others fins reddish. Skeleton with 39-42 vertebrae.

Foto: Pietro Ceccuzzi

2 cm Habitat Slow flowing rivers, deep lakes and The Baltic sea near Stockholm ponds, but also common in the Baltic Sea. Usually found near submersed obstacles. Temperature: 10 – 22°C.

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Foto: A.G. Cattaneo

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o Geographical distribution: Europe and t

o Siberia (native). Originally absent in Lago Maggiore near Varese, Italy F Italy, Spain, Greece and Great Britain, has been successfully introduced since XVIII century (from 1860 in Italy). Largely cultured for commercial purposals also in the Southern hemisphere (Australia). Feeding and Behaviour

Predator: • Larval stage: zooplankton. • Juvenile and adult life: zooplankton, zoobenthos and nekton.

Can be predated by Anguilla anguilla, Sander lucioperca and other fishes.

Swimming type: carangiform, by movements of body and of the caudal fin. Speed: 0,5-1 m/h. Reproduction Reproduction: dioecism, external fertilization, polyandria. Spawning: in open waters, once a in spring (autumn in the Southern hemisphere). Foto: Pietro Ceccuzzi Eggs: in jelly matrix and in ribbons 1 m long and bound to a substratum. Early development: fertilized eggs

Eggs: white, spherical, embedded in a jelly and whitish matrix. (The picture shows eggs 14 hours after fertilization). Foto: Pietro Ceccuzzi Early development: egg with embryo

Eggs hatch in 8–16 days after deposition. Larvae develop in 37 days at 13°C. Dry weight: • 164 µg at hatching • 11600 µgat metamorphosis.

Foto: Pietro Ceccuzzi Young adults

Younger individuals are gray, with traversal bands on sides darker than in adult. Lateral shape is more elongated. Sex, determined since birth, can be identified at 1+.

1 cm Foto: Pietro Ceccuzzi Fully developed adult

Foto: Pietro Ceccuzzi Body symmetric, cross section compressed, lateral shape short and deep. Head is convex, mouth terminal. Age range: 2-3 y (M) 3-5 y (F)

(2 cm) Links and sources NCBI Base ITIS, Integrated Taxonomy Information System