| Stegastes fuscus | |
|---|---|
 | |
| Stegastes fuscus | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Family: | Pomacentridae |
| Genus: | Stegastes |
| Species: | S. fuscus |
| Binomial name | |
| Stegastes fuscus | |
| Synonyms [2] [3] | |
| |
Stegastes fuscus, the dusky damselfish, is a species of bony fish in the family Pomacentridae found near the seabed in shallow waters on the western fringes of the Atlantic Ocean. [3]
The colour of an adult dusky damselfish varies from brownish-olive to dark grey, with fine, darker-coloured, vertical stripes on the body. The fins are large with sometimes a blue rim around the edge of the dorsal and anal fins. The dorsal fin has 12 spines and 15-16 soft rays while the anal fin has two spines and 13-14 soft rays. [3] The dusky damselfish can be distinguished from the very similar longfin damselfish ( Stegastes diencaeus ) by the shorter, less angular dorsal and anal fins. The maximum length is 15 cm (5.9 in), but 10 cm (3.9 in) is a more typical length. [4]
The juvenile dusky damselfish is pearly grey with blue spots on the top of its head. It has a large, blue-rimmed, black eyespot where the dorsal fin spines meet the dorsal fin soft rays, and a smaller, similarly coloured eyespot on the caudal peduncle. Some juveniles off the coast of southeastern Brazil have a vivid yellow and orange band on the back and dorsal fin. [5]
Stegastes fuscus occurs in shallow waters off Brazil, where it is common on both rocky and coral reefs at depths down to 40 m (130 ft). It is also reported from the Caribbean Sea, but another species, Pomacentrus dorsopunicans , possibly was misidentified there. Another population is reported from Senegal, but this lacks confirmation. [3] [6]
About 70% of the food consumed by the dusky damselfish consists of algae, mostly red, filamentous algae, but some calcareous algae are also eaten. The rest of their diet is small invertebrates. The feeding activities of the damselfish prevent coarser seaweeds, such as Jania spp., becoming dominant and greatly influences the structure of the benthic community. [7]
The dusky damselfish is a territorial species. It guards part of the seabed and repels intruders, sometimes chasing away fish several times its own size. [8] The richer the site was in suitable algae for feeding, the more aggressive the fish became. Besides members of its own species, the main species chased away were parrotfish, bluehead wrasse ( Thalassoma bifasciatum ), bicolour damselfish ( Stegastes partitus ) and ocean surgeonfish (Acanthurus bahianus). Certain other fish species, such as the smooth trunkfish ( Rhinesomus triqueter ) and the graysby (Cephalopholis cruentata), were not chased away. The author of the study surmised it was the food source rather than the geographical area being guarded, and these fish were not considered to be threats because they did not graze algae, instead feeding on small invertebrates. An alternative possibility was these fish benefited the dusky damselfish in some other way, such as by providing some protection against predators or by removing invertebrates that feed on algae. [4]
Pomacentridae is a family of ray-finned fish, comprising the damselfishes and clownfishes. This family were formerly placed in the order Perciformes but are now regarded as being incertae sedis in the subseries Ovalentaria in the clade Percomorpha. They are primarily marine, while a few species inhabit freshwater and brackish environments. They are noted for their hardy constitutions and territoriality. Many are brightly colored, so they are popular in aquaria.
Stegastes is a genus of ray-finned fish in the family Pomacentridae. Members of this genus are marine coastal fishes except for S. otophorus, which also occurs in brackish water. These fish are known by the names of damselfish, gregory and major. They are small tropical fish associated with coral and rocky reefs in the Atlantic, Indian and Pacific Oceans. They are sometimes found in the aquarium trade where they are an easy-to-keep fish, but they do not mix well with other fish of their own or other species because of their territorial habits and aggressiveness.
Stegastes nigricans, the dusky farmerfish, is a species of damselfish found around coral reefs at a depth of one to 12 meters, in tropical climates between 30°S and 30°N. They are known for farming monocultures of algae such as cyanophores and rhodophytes.
The Indo-Pacific sergeant is a species of damselfish in the family Pomacentridae. It may also be known as the Sergeant major although this name is usually reserved for the closely related species Abudefduf saxatilis. The closely related Abudefduf caudobimaculatus was formerly considered to be synonymous with this species and, according to some authorities, is synonymous.
Stegastes variabilis, commonly known as the Brazilian cocoa damselfish, is a species of damselfish in the family Pomacentridae, found on coral reefs in the western Atlantic Ocean and off Brazil. They are often solitary fish.
The smallmouth scad, is a species of tropical marine fish in the jack family Carangidae. The species is endemic to northern Australia, inhabiting primarily inshore waters. It is similar to other scads in the genus Alepes, and is distinguished by a well-developed posterior adipose eyelid, as well as fin membrane spotting and gill raker counts. It is not a large species, with the maximum length reported to be 29.5 cm. It feeds primarily on a variety of small invertebrates, and is of very minor economic importance.
Parachaetodon is a monotypic genus of butterflyfishes, the only species being the sixspine butterflyfish, which is also known as the ocellate butterflyfish or eyespot butterflyfish. is a species of butterflyfish native to tropical reefs of the eastern Indian Ocean and the western Pacific Ocean.
Chromis chromis, the damselfish or Mediterranean chromis, is a small species of ray-finned fish of the family Pomacentridae from the Eastern Atlantic and Mediterranean.
Pomacentrus coelestis, the neon damselfish, is a species of damselfish in the family Pomacentridae. It is found in the Indo-Pacific. It can grow to a maximum size of 9 centimetres (3.5 in) in length. It occasionally makes its way into the aquarium trade.
Stegastes planifrons is a damselfish from the Western Atlantic. It occasionally makes its way into the aquarium trade.
Stegastes pictus, the yellowtip damselfish, is a species of damselfish found near the sea bed on shallow rocky reefs off the coast of Brazil, where it is endemic. It is a small, laterally-compressed, dark brown fish with yellow pectoral and caudal fins. It feeds on algae and detritus and is often found in the vicinity of the fire coral Millepora alcicornis. It is a territorial fish and forms a pair bond in the breeding season. The eggs are laid in a shallow scoop on the seabed and the male tends them to keep them well-aerated.
Stegastes leucostictus is a species of damselfish found near the sea bed in shallow waters on the western fringes of the Atlantic Ocean. It is commonly known as the beau gregory or beaugregory.
Stegastes partitus or the bicolor damselfish is a species of bony fish in the family Pomacentridae found near the sea bed on shallow rocky and coral reefs in the Caribbean Sea, the Gulf of Mexico and off the coasts of Florida.
Stegastes beebei, is a species of damselfish found on coral and rocky reefs at depths between 0 and 15 m. They are somewhat territorial, and chase away small intruders. They are omnivorous, grazing on algae and nibbling at small crustaceans and the tentacles of anemones. They are oviparous, with distinct pairing during breeding. The eggs are demersal and adhere to the substrate. Males guard and aerate the eggs.
The Barrier Reef chromis, also known as the yellowback puller or shining puller, is a species of damselfish in the family Pomacentridae native to the east coast of Australia. It is a small fish with a yellowish-brown dorsal surface separated by a dark stripe from its silvery flanks and underside.
Plectroglyphidodon sindonis is a species of damselfish in the family Pomacentridae. It is found in the Pacific Ocean.
Plectroglyphidodon imparipennis is a species of damselfish in the family Pomacentridae. It is found in the Indo-Pacific.
The Canary damsel is a species of marine fish of the family Pomacentridae. It lives primary in shallow, subtropical waters of the Atlantic Ocean, and is sometimes also known as the Cape Verde gregory, which is also a common name of Stegastes imbricatus.
Plectroglyphidodon dickii, common name blackbar devil, Dick's damsel or narrowbar damselfish, is a species of damselfish in the family Pomacentridae. This species was formerly classified as Dascyllus aruanus, but recently the populations of western Indian Ocean and Pacific Ocean have been split off.
Stegastes xanthurus, also known as the Caribbean cocoa damselfish, is a species of damselfish in the family Pomacentridae, found on coral and rocky reefs in the Caribbean Sea and neighboring areas of the Atlantic Ocean and Gulf of Mexico.
