Peacock Wrasse
| Peacock Wrasse | ||||||||||||
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Symphodus tinca , male (middle) and female (top, bottom) |
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| Scientific name | ||||||||||||
| Symphodus tinca | ||||||||||||
| ( Linnæus , 1758) |
The peacock wrasse ( Symphodus tinca ; English East Atlantic peacock wrasse) is a representative of the genus Symphodus within the family of wrasse (Labridae) that occurs in the Mediterranean and the bordering Black Sea . It is at S. tinca the largest members of this genus in the Mediterranean. Its primary habitat is formed by rocky coastal regions ( littoral ), in which reproduction, including mating, also takes place. In addition, numerous benthic invertebrates can be found there, which are the main food source of S. tinca . In addition, the peacock wrasse is characterized, among other things, by a sexual dimorphism , which is mainly reflected in its color.
General
The peacock wrasse was first described in 1758 by the Swedish scientist Carl von Linné ("Linnaeus") under the name Labrus tinca . However, over the years other synonyms have also been used, such as, Labrus lapina Forsskål, 1775, Lutjanus lapina (Forsskål, 1775) and Labrus polychrous Pallas, 1814.
Anatomy and appearance
In S. tinca is the largest species of the genus Symphodus in the Mediterranean. The males have a greater mean total body length than the females. As with all wrasse, their mouth is also characterized by so-called "lips", which in S. tinca are pointed, bulging and pronounced. The body is elongated oval and laterally flattened. The head is longer than the body height. Furthermore, S. tinca has a very long dorsal fin (dorsalis) that extends almost to the caudal fin (caudalis). As with many other species within the wrasse family, a pronounced sexual dimorphism in terms of coloration can also be seen in the peacock wrasse . While females are grayish to greenish or olive in color and have two to three longitudinal dark brown stripes, males are characterized by a colorful appearance , especially during the spawning season . After they go through a transitional coloration as young fish, in which they are uniformly beige in color and the spot on the tail stalk is mostly missing or the tail gradually turns completely dark, the S. tinca males reach their final color, which is characterized by striking bright yellow colors and numerous red dots, which are usually arranged in two to three longitudinal stripes. In addition, a lot of blue spots can be found, especially on the fins. An almost black forehead band and a dark spot each at the base of the caudal fin (caudalis) and just above the pectoral fin (pectoralis) appear in both sexes.
Due to the homogeneous beige color as a young animal, the peacock wrasse can possibly be confused with the gray wrasse ( S. cinereus ). As an adult, however, the gray wrasse remains much smaller, is not so colorful and, unlike the peacock wrasse, has a dark spot on the base of the dorsal fin (dorsalis).
Labrids, including the peacock wrasse, are characterized by their labriform swimming style, in which the pectoral fins (pectoralia) form the main driving organ. Here S. tinca beat them back and forth at the same time and use the caudal fin (caudalis), except when there is danger and flight has to be taken, only for steering.
Habitat and occurrence
S. tinca occurs in the entire Mediterranean, in the bordering Black Sea and in the eastern Atlantic from northern Spain to Morocco. In the Mediterranean, the peacock wrasse is one of the most common wrasse species. This species prefers rocky coasts (littoral). The primary habitat are areas with large boulders. It also occurs in salty lagoons and in seagrass meadows ( Posidonia meadows). S. tinca can be found both in shallow water and at great depths of up to 80 meters. The peacock wrasse is most often found at a depth of three to twelve meters.
nutrition
S. tinca are omnivorous . Their main food component are benthic invertebrates. These include sea urchins ( Echinoidea ), brittle stars ( Ophiuroidea ), clams ( Bivalvia ), polychaetes and crustaceans ( Crustacea ), as well as shrimp and especially copepods ( Copepoda ). In S. tinca is a robber, acting as lurking predators or he chews the sand for something to eat by spitting the inedible parts again.
When looking at success in foraging for food, height plays a major role. As fish grow, they tend to expand their range of prey, e.g. B. to catch and ingest larger prey. This phenomenon is due to the increasing ontogenetic development of the mouth, visual acuity, digestive capacity (digestion) and improved swimming performance. Therefore, morphological characteristics such as the size and shape of the mouth and the body size determine what type of prey is or can be consumed. The total length of the peacock wrasse, which is usually around 25 cm, and their mouth shape are particularly suitable for accommodating the prey listed above.
Reproduction and rearing
The females of this species become sexually mature at two years and a body length of ten centimeters, the males, however, at two to three years and a body length of about eleven centimeters. The maximum achievable age of S. tinca is between 14 and 15 years. The reproduction of S. tinca takes place in spring. The spawning season is very region-specific, but extends roughly from March to June. For example, in Italy, females spawn from April to May, in France from April to July, and in North Africa from March to June.
In S. tinca is a ovipare reproductive form, the females already lays fertilized eggs. While all other species of the genus Symphodus build their nests themselves, this is not the case with S. tinca . Rather, the females lay their fertilized eggs on algae-covered boulders. In contrast to S. ocellatus and S. roissali , the S. tinca males do not build an elaborate nest. The male's task is to protect the eggs on the one hand and to maintain the algae nest for a relatively long time, on average 31.4 days, on the other. This takes an average of around 31.4 days. However, this does not take place in separate periods of time, as is the case with S. ocellatus and S. roissali , for example , but at irregular intervals during the entire period of nesting.
In addition, there is a correlation between the size of the animal and the success of reproduction in the peacock wrasse. The larger the male, the more successful the reproduction.
In addition, a protogynous hermaphrodism can occur in this species and thus there is an occasional change of sex. However, this is rarely the case. In studies by Warner (1985), for example, signs of a change of sex were observed in only two individuals out of a total of 46 males.
Other properties
Mauthner's cells
So- called Mauthner's cells are located in the brain of S. tinca . These are neurons that play a role in the escape reflex. With the so-called C-Start, the fish curve into a C-shape within a few milliseconds, in order to be able to flee from the enemy as quickly as possible. Only the Mauthner's cells decide whether the input of various sensory cells is sufficient to trigger an action potential and whether the muscle cells are signaled to contract quickly. In the peacock wrasse and all other fish that have such cells, the Mauthner's cells are located at a specific location in the immediate vicinity of the entry point of the vestibular nerve and lateral to the medial longitudinal fasciculus in the floor of the fourth ventricle. The larger the peacock wrasse, the larger the Mauthner's cells, of which only one occurs in each hemisphere . However, both are on the same cross-sectional plane.
Activity as cleaner fish
In addition to the black-tailed wrasse ( S. melanocercus ), there are other wrasses in the Mediterranean that “work” as cleaner fish . This also includes the peacock wrasse, which, however, only performs cleaning activities as a young animal. Cleaning activities are the acquisition of food by cleaning other fish species. Fish that want to be cleaned to get rid of their skin parasites are called customers. Those customers stand upside down or vertically in the water and position their fins and gills so that the cleaner fish, e.g. B. S. tinca , which can eliminate skin parasites in the folds of the fin and the gill cavities. Occasionally, customers open their mouths for this.
In addition to S. tinca and S. melanocercus , other Mediterranean wrasse are also active as cleaners, such as. B. the sea peacock ( Thalassoma pavo ) or the mermaid ( Coris julis ). S. tinca is not only a cleaner himself, this species also often acts as a “customer”. Adult animals in particular can be removed from other cleaner wrasse, mostly from S. melanocercus juveniles, marine isopods.
sleep
The sleep of the diurnal peacock wrasse is characterized by the fact that it lies motionless on its side at night and floats in the water. Even bright headlights, for example from boats or divers, only make him wake up very slowly. Thus it is endangered by potential predators especially during this sleep phase .
Due to the often missing eyelids of fish, "human" sleep is rarely perceived in the fish world. However, it is clear that in fish such. B. S. tinca , the frequency of the gill cover movement is significantly reduced during the resting phase.
meaning
fishing
One could assume that their “sociable” and “indifferent” nature makes them easy prey and that they are widespread on the fish market. But that's not the case. In S. tinca is a child eating fish that the game fish is counted and is sold at a catch only local fisheries sometimes. The low catch rate may also have something to do with the fact that it is mainly in coastal regions ( littoral ) and is therefore not easily accessible for fishermen.
Aquarium keeping
Another aspect to be considered is the keeping of S. tinca in aquariums. In general, it can be said that small to medium-sized wrasse species, including the Symphodus genus , can certainly be kept privately in aquariums, provided that the dimensions of the aquarium meet recognized standards. However, since wrasse are naturally permanent swimmers and therefore need more space, an aquarium should be made available to them as large as possible. If this is not the case, stereotypes such as B. repeated swimming up and down on the aquarium walls develop. Since S. tinca is the largest representative of the labrids in the Mediterranean, the keeping of adult peacock wrasses in aquariums can be viewed critically and accordingly viewed as unsuitable.
Threats
For S. tinca there is no apparent major threats, remains relatively stable so that their population. The peacock wrasse is therefore not on the red list of endangered species.
According to surveys, S. tinca is said to be infested with some types of parasites. Known incidents, however, have only been described on the Tunisian coast. On the one hand, a number of parasites were found in the gill arches of the peacock wrasse examined. These were white plasmodia of a myxospore species belonging to the group of Henneguya tunisiensis n. Sp. heard. On the other hand, parasites were discovered that attack the liver. It was z. B. to Microgemma tincae n. Sp. A strong microsporidial infestation was found particularly in juvenile and smaller animals.
swell
- ↑ a b c Pollard, D. (2010). Symphodus tinca. IUCN (International Union for Conservation of Nature and Natural Resources): The IUCN Red List of Threatened Species
- ↑ a b c d e f g h i j k l m n o Neumann, V .; Paulus, T. (2005): Mediterranean Atlas: Fish and their habitats. Mergus Verlag GmbH for nature and pet science, Melle
- ↑ a b c Patzner, R .; Moosleitner, H. (2006): Underwater Guide Mediterranean: Fish. 3. Edition. Verlag Stephanie Naglschmid, Stuttgart
- ↑ a b c d e f g h Göthel, H. (1997): Color Atlas Mediterranean Fauna: Lower Animals and Fish. 2nd Edition. Publishing house Eugen Ulmer, Stuttgart
- ↑ a b c d Pallaoro, O., & Jardas, I. (2003). Some biological parameters of the peacock wrasse, Symphodus (Crenilabrus) tinca (L. 1758) (Pisces: Labridae) from the middle eastern Adriatic (Croatian coast). Scientia Marina, 67 (1), 33-41
- ↑ a b c Louisy, P. (2002): Marine fish Western Europe Mediterranean. 750 types - 800 color photos - 1000 drawings and maps. Publishing house Eugen Ulmer, Stuttgart
- ↑ Reininger, M. (2012): Competition in the coral reef: Mimicry as a strategy of young fish. In: Biology in Our Time 4, 254–259.
- ↑ a b c d Warner, RR, & Lejeune, P. (1985). Sex change limited by paternal care: a test using four Mediterranean labrid fishes, genus Symphodus. Marine Biology, 87 (1), 89-99
- ↑ García-Rubies, A., & Macpherson, E. (1995). Substrate use and temporal pattern of recruitment in juvenile fishes of the Mediterranean littoral. Marine biology, 124 (1), 35-42
- ↑ a b Karpouzi, VS, & Stergiou, KI (2003). The relationships between mouth size and shape and body length for 18 species of marine fishes and their trophic implications. Journal of fish biology, 62 (6), 1353-1365
- ↑ a b c d Papasissi, C. & Luna, SM (no year). Symphodus tinca - East Atlantic peacock wrasse. FishBase - A Global Information System on Fishes
- ↑ Bauchot & Fisher, W., MLM Schneider, 1987.-Fiches FAO d'identification des espèces pour les besoins de la pêche "Révision 1" Méditerranée et Mer noire. Zone de pêche 37. Volume I. Inverted marins. Rome, FAO, 2, 761-1530
- ↑ Otsuka, N. (1964) Further comparative anatomical studies on Mauthner's cells from fish. Cell and Tissue Research, 62 (1), 61-71.
- ↑ Bahri, S., Marton, S., Marques, A., & Eszterbauer, E. (2010). Henneguya tunisiensis n. Sp. (Myxosporea: Bivalvulida), a new gill parasite of Symphodus tinca (L.) (Teleostei: Labridae) off Tunisia. Systematic parasitology, 76 (2), 93-101.
- ↑ Mansour, L., Prensier, G., Jemaa, SB, Hassine, OKB, Méténier, G., Vivarès, CP, & Cornillot, E. (2005). Description of a xenoma-inducing microsporidian, Microgemma tincae n. Sp., Parasite of the teleost fish Symphodus tinca from Tunisian coasts. Diseases of aquatic organisms, 65 (3), 217-226.
Web links
- Peacock Wrasse on Fishbase.org (English)