Fishes

Thursday, 26 July 2012

Holocentridae

The Holocentridae is a family of ray-finned fish, belonging to the order Beryciformes with the members of the subfamily Holocentrinae typically known as squirrelfish, while the members of Myripristinae typically are known as soldierfish. In Hawaii they are known as menpachi.They are found in tropical parts of the Indian, Pacific and Atlantic Oceans, with the greatest species diversity near reefs in the Indo-Pacific. Most are found at depths from the shoreline to 100 m (330 ft), but some, notably the members of the genus Ostichthys, are generally found far deeper. Being largely or entirely nocturnal, they have relatively large eyes. During the day they typically remain hidden in crevices, caves, or under ledges.Red and silvery colours dominate. The preopercle spines (near the gill-opening) of the members of the subfamily Holocentrinae are venomous, and can give painful wounds. Most have a maximum length of 15–35 cm (6–14 in), but Sargocentron iota barely reaches 8 cm (3 in), and S. spiniferum and Holocentrus adscensionis can reach more than 50 cm (20 in). The squirrelfishes mainly feed on small fishes and benthic invertebrates,while the soldierfishes typically feed on zooplankton. The larvae are pelagic, unlike the adults, and can be found far out to sea.

Holocentridae

Beryciformes

Beryciformes is an order of ray-finned fishes. This is a very poorly understood group of 16 families, 57 genera, and about 219 species. Some people believe that it is probably an artificial assemblage of unrelated taxa that are thrown together for convenience only; there are no convincing characteristics that tie all members together. Most species live in deep marine waters, and avoid bright light, although they may come closer to the surface at night.Traditionally three grades of actinopterygians have been recognised: the Chondrostei, Holostei, and Teleostei. Some morphological evidence suggests that the second is paraphyletic and should be abandoned; however, recent work based on of orders, arranged in what has been suggested to represent the evolutionary sequence down to the level of order based primarily on the long history of morphological studies. This classification, like any other taxonomy based on phylogenetic research is in a state of flux. Recent morphological and molecular data has shown that several of these ordinal and higher-level groupings represent evolutionary grades rather than clades. Examples of demonstrably paraphyletic groups include the Paracanthopterygii, Scorpaeniformes, and Perciformes. The listing follows FishBas with notes when this differs from Nelsonand ITIS.

Beryciformes

Aeoliscus Strigatus

Aeoliscus strigatus, also known as the razorfish, is a member of the family Centriscidae of the order Gasterosteiformes. This unique fish adopts a head-down tail-up position as an adaptation for hiding among sea urchin spines.The razorfish is generally found in coastal waters from the central Indian Ocean to the Red Sea to Hawaii. Its natural habitat includes beds of sea grass and coral reefs, where sea urchins are found.The dorsal surface of the razorfish is covered by protective bony plates. They extend past the end of the golden yellow body and over the tail fin, which terminates in a sharp spine. A dark band runs the length of the fish. The razorfish can grow up to 6 in (15 cm) in the wild.The razorfish is considered a hardy fish in regards to temperature and pH. As long as the temperature is within the commonly accepted range of "tropical" and the pH is between 7.8–8.3, it will be fine. Salinity should be roughly 30 parts per thousand.

Aeoliscus Strigatus

Aeoliscus

The razorfish eats mainly small brine shrimp and other invertebrates.They have also been known to eat minute crustaceans in the zooplankton. In the wild they have been observed hiding in the spines of sea urchins, both as a defense mechanism and as a hunting mechanism. When threatened by larger fish, the razorfish darts away to a nearby sea urchin. The larger fish, wary of being stung by the sea urchin, which can sometimes be deadly, gives up the chase. They also hide in the spines for a completely different reason. When hunting, razorfish will hide among the sea urchin spines an wait for small invertebrates that feed on the urchins. When their prey gets close the razorfish will dart out and try to catch its

Aeoliscus

Centriscidae

Centriscidae is the family of snipefishes, shrimpfishes, and bellowfishes.A small family, consisting of only about a dozen marine species, they are of an unusual appearance, as reflected by the common names. The members of the genera Aeoliscus and Centriscus are restricted to relatively shallow, tropical parts of the Indo-Pacific, while the remaining species mainly are found in deeper parts of tropical, subtropical or southern oceans.The bodies are highly compressed, and mostly covered with bony plates. The first spine of the dorsal fin is long and sharp, and displaced to the rear of the body; two additional spines, the rest of the dorsal fin, and the caudal fin have all moved to the ventral side of the fish. The snout is also long and narrow, and the small mouth at the end has no teeth. All species are small, no more than 34 centimetres (13 in).As if the shape were not strange enough, centriscids also swim head down. The reason for this is unclear; while some species blend in with sea grass, others live on coral reefs, where there is no apparent advantage to vertical positioning. They feed on zooplankton

Centriscidae

Hippocampus Erectus

The lined seahorse (Hippocampus erectus), northern seahorse or spotted seahorse is a species of fish that belongs to the Syngnathidae family. H. erectus is a diurnal species with an approximate length of 15 centimeters (6 inches) and lifespan of one to four years. The H. erectus species consists of a broad color spectrum, ranging from greys and blacks to reds, greens, and oranges. The lined seahorse resides in the Atlantic Ocean from Canada down to the Caribbean, Mexico, and Venezuela. It swims in an erect position and uses its dorsal and pectoral fins to guide itself when propelling through the water.Lined seahorses feed mainly on minute crustaceans and brine shrimp, which they suck in through their snout. Since the species consists of weak swimmers, they must ambush their prey by blending into their surroundings, which they do rather easily. The lined seahorse has eyes that can move independently of one another, allowing it to scan its surroundings rather easily and quickly. The species is sexually dimorphic, meaning it is easy to distinguish between a male and female lined seahorse; the males are larger and have longer tails. The lined seahorse is monogamous and perform ritual dances every morning in order to establish a bond with its mate, in addition to the clicking sounds and embraces that occur when they initially find their mate. If either the male or female should die, its mate would take time before replacing it with a new mate, if it does not die due to its short lifespan.

Hippocampus Erectus

Hippocampus Kuda

Hippocampus kuda, also known as the common seahorse, is a member of the family Syngnathidae of the order Syngnathiformes. The common sea horse is a small, equine-like fish, with extraordinary breeding methods.Greeks and Romans believed the seahorse was an attribute of the sea god Poseidon/Neptune, and the seahorse was considered a symbol of strength and power. Europeans believed that the seahorse carried the souls of deceased sailors to the underworld - giving them safe passage and protection until they met their soul's destination. The common seahorse is considered a vulnerable species.The sea horse's swimming position is vertical, with slight forward or backward inclinations, in the direction of travel. The body is covered with armored plates. An equine-like head set at right angles to the body ends in a long tubular snout. A bony "coronet" may develop on the head.The male seahorse broods fertilized eggs in a small pouch in its lower abdomen. Females are slightly smaller.

Hippocampus Kuda