Percalates novemaculeata
| Percalates novemaculeata | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Percalates novemaculeata |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Percalates novemaculeata | ||||||||||||
| ( Steindachner , 1866) |
Percalates novemaculeata is an Australian fresh and brackish water fish found in the coastal rivers and lagoons of southeastern Australia. The distribution area extends from the Great Sandy Strait in the southeast of the state of Queensland to the region of Gippsland in eastern Victoria. Percalates novemaculeata is a popular frogfish in its homeland and is called the Australian Perch, Eastern Freshwater Perch, Freshwater Perch or simply Perch.
features
Percalates colonorum has a typical, laterally flattened perch shape and can reach a maximum length of 60 cm and a weight of 3.8 to a maximum of 4.5 kg. The mouth is large and above all. At the back it reaches under the eye. The lower jaw protrudes. The jaw and palate are covered with small teeth arranged in bands. The preoperculum is finely serrated on the upper branch and has a strong, forward-facing spine on the lower branch. The gill cover is equipped with two spines, the lower one of which is larger and wider. The scales are medium in size and usually comb scales . "Cheeks" and gill covers are also scaly. The snout, in fish the area between the front edge of the eye and the tip of the mouth, is not scaly. The side line is fully developed and follows the back line in its course. The hard and soft rayed sections of the dorsal fin are separated from one another by an indentation. The fourth dorsal fin spine is the longest. The anal fin is symmetrically opposite the soft-rayed section of the dorsal fin. It has three short spines. The upper rays of the pectoral fins are longer than the lower. The base of the pelvic fins is just behind the pectoral fin base. The caudal fin is slightly indented.
- Fin formula : dorsal VIII-IX / 8-11, anal III / 7-9, pectoral 12-16
- Scale formula : SL 48-55, mLR 25-30
- Vertebra: 25
On the back, the fish are greenish-gray to olive-colored and become increasingly lighter down to the yellowish-white belly. The pectoral fins are darker at the base, the pelvic fins and the anal fin have white tips. The lower rays of the pelvic fins are white. Young fish up to a length of 12 cm have dark spots between the spines on the gill cover, show four to six weakly developed vertical stripes on the back and sides of the body and dark markings on the dorsal, anal and pelvic fins. Freshly caught fish often have red eyes. The color disappears quickly after the fish are taken out of the water.
Percalates novemaculeata can easily be confused with Percalates colonorum , its only close relative, and hybridizes with this species in the catchment area of the Snowy River and in the Gippsland region . Percalates novemaculeata and Percalates colonorum can be distinguished from each other by the laterally more flattened body, the straight or only slightly concave head profile, the somewhat darker, less silvery color and the gray anterior dorsal fin spines of P. novemaculeata .
Way of life
Percalates novemaculeata occurs in rivers, streams, lakes and in slightly brackish estuaries. The species prefers to stay between aquatic plants or rocks or in gravelly depressions. They are migratory fish that visit the estuaries to spawn between May and August. The numerous small eggs are laid between water plants or on sandbars. They are round, transparent, do not stick and float freely in the water. The fry hatch after two to three days and are then about 2.5 mm long. After spawning, both sexes migrate upriver again. However, the males usually stay in the lower reaches of the rivers, while the females swim up to the upper reaches. Percalates novemaculeata feeds on small fish, mollusks, crustaceans, and other invertebrates. Young fish eat zooplankton.
Systematics
The species was in 1866 by the Austrian zoologist Franz Steindachner under the name Dules novemaculeata first described scientifically, so then the Sägebarschen assigned (Serranidae). Later it was transferred to the genus Macquaria , which belongs to the cod perch (Percichthyidae). In a phylogenetic study on the relationship of bony fish, first published in 2013, however, the result was that Percalates novemaculeata and Percalates colonorum do not belong to the genus Macquaria and to the codfish, but form a separate clade within the order Centrarchiformes . Therefore, it was proposed to transfer both species to the genus Percalates , which was introduced in 1887 by the Australian zoologists James Douglas Ogilby and Edward Pierson Ramsay with Lates colonorum as the type species , and to establish a monotypical family Percalatidae for Percalates . Both suggestions have now been incorporated into Eschmeyer's Catalog of Fishes, a monthly updated database on fish classification.
supporting documents
- ↑ a b c d e f g Dianne J. Bray & Vanessa J. Thompson, Macquaria novemaculeata in Fishes of Australia , accessed March 23, 2019.
- ↑ a b c d Macquaria novemaculeata on Fishbase.org (English)
- ↑ a b Percalates novemaculeata in the Catalog of Fishes (English)
- ↑ Ricardo Betancur-R, Edward O. Wiley, Gloria Arratia, Arturo Acero, Nicolas Bailly, Masaki Miya, Guillaume Lecointre and Guillermo Ortí: Phylogenetic classification of bony fishes . BMC Evolutionary Biology, BMC series - July 2017, DOI: 10.1186 / s12862-017-0958-3