Manta ray [Manta birostris]

The Manta ray, Manta birostris, is the largest of the rays, with the largest known specimen having been about 7.6 m (about 25 ft) across, with a weight of about 2,300 kg (about 5,000 lb). It ranges throughout all tropical waters of the world, typically around coral reefs.

Mantas have been given a variety of common names, including Atlantic manta, Pacific manta, devilfish, and just manta. Some people just call all members of the family stingrays, though stingrays comprise a separate family of rays (Dasyatidae).

Mantas are most commonly black dorsally and white ventrally, but some are blue on their backs. A manta’s eyes are located at the base of the cephalic lobes on each side of the head, and unlike other rays the mouth is found at the anterior edge of its head. To respire, like other rays, the manta has five pairs of gills on the underside.

To swim better through the ocean, they have a diamond shaped body plan, using their pectoral fins as graceful “wings”.

Distinctive “horns” (from which the common name Devil ray stems) are on either side of its broad head. These unique structures are actually derived from the pectoral fins. During embryonic development, part of the pectoral fin breaks away and moves forward, surrounding the mouth. This gives the manta ray the distinction of being the only jawed vertebrate to have novel limbs (the so-called six-footed tortoise, Manouria emys, does not actually have six legs–only enlarged tuberculate scales on their thighs that look superficially like an extra pair of hind limbs). These flexible horns are used to direct plankton, small fish and water into the manta’s very broad and wide mouth. The manta can curl them to reduce drag while swimming.

Taxonomically, the situation of the mantas is still under investigation. Three species have been identified: Manta birostris, Manta ehrenbergii, and Manta raya, but they are quite similar, and the latter two may just be isolated populations. The genus Manta is sometimes placed in its own family, Mobulidae, but this article follows FishBase taxonomy, and places it in the family Myliobatidae, along with eagle rays and their relatives.

Mantas are filter feeders: they feed on plankton, fish larvae and the like, passively filtered from the water passing through their gills as they swim. The small prey organisms are caught on flat horizontal plates of russet-coloured spongy tissue, that span the spaces between the manta’s gill bars.

Mantas are extremely curious around humans, and are fond of swimming with scuba divers. Although they may approach humans, if touched, their mucus membrane is removed, causing lesions and infections on their skin. They will often surface to investigate boats (without engines running). They have the largest brain-to-body ratio of the sharks and rays. Mantas are known to breach the water into the air.

Picture: Cozumel, Mexico by Sami Salmenkivi

 

Needlefish

Needlefish is the family (Belonidae), but information on the different species cannot be found. But if you do know more, feel free to assist.

Needlefish (family Belonidae) are piscivorous fishes primarily associated with very deep marine habitats or the bottom of the open sea. Some genera include species found in marine, brackish, and freshwater environments (e.g., Strongylura) while a few genera are confined to freshwater rivers and streams, including Belonion, Potamorrhaphis, and Xenentodon. Needlefish closely resemble North American freshwater gars (family Lepisosteidae) in being elongate and having long, narrow jaws filled with sharp teeth, and some species of needlefish are referred to as gars or garfish despite being only distantly related to the true gars. Needlefish are in fact members of the Beloniformes and therefore most closely related to flying fish, sauries, and halfbeaks.

Picture: Pulau Redang, Malaysia by Sami Salmenkivi

 

Great barracuda [Sphyraena barracuda]

The Great Barracuda is a species of barracuda. Its binomial name is Sphyraena barracuda. Great barracudas often grow over 6ft long. The great barracuda is a type of ray-finned fish.

Barracudas are elongated fish with powerful jaws. The lower jaw of the large mouth juts out beyond the upper. Barracudas possess strong, fang-like teeth. These are unequal in size and set in sockets in the jaws on the roof of the mouth. The head is quite large and is pointed and pike-like in appearance. The gill-covers do not have spines and are covered with small scales. The two dorsal fins are widely separated, with the first having five spines and the second having one spine and nine soft rays. The second dorsal fin equals the anal fin in size and is situated more or less above it. The lateral line is prominent and extends straight from head to tail. The spinous dorsal fin is placed above the pelvics. The hind end of the caudal fin is forked or concave. It is set at the end of a stout peduncle. The pectoral fins are placed low down on the sides. The barracuda swim bladder is large.

In general, the barracuda’s coloration is dark green or grey above chalky-white below. This varies somewhat. Sometimes there is a row of darker cross-bars or black spots on each side. The fins may be yellowish or dusky.

Barracudas appear in open seas. They are voracious predators and hunt using a classic example of lie-in-wait or ambush. They rely on surprise and short bursts of speed (up to 27mph (43 km/h)[2]) to overrun their prey, sacrificing maneuverability. Barracudas are more or less solitary in their habits. Young and half-grown fish frequently congregate in shoals. Their food is composed almost totally of fishes of all kinds. Large barracudas, when gorged, may attempt to herd a shoal of prey fish in shallow water, where they guard over them until they are ready for another meal. (text source: wikipedia)

Picture: Cozumel, Mexico by Sami Salmenkivi

 

Creole Wrasse [Clepticus parrae]

(left female, right male)

Wikipedia has no description for Creole Wrasse or Clepticus parrae.

Picture: Cozumel, Mexico by Sami Salmenkivi

 

Porkfish [Anisotremus virginicus]

Wikipedia has no article on Porkfish.

Picture: Cozumel, Mexico by Sami Salmenkivi

 

French grunt [Haemulon flavolineatum]

Wikipedia has no article on French grunt.

Picture: Utila, Honduras by Sami Salmenkivi

 

Bluestriped grunt [Haemulon sciurus]

Wikipedia has no article on Bluestriped grunt.

Picture1: Roatan, Honduras, pic2: Cozumel, Mexico  by Sami Salmenkivi

 

Oriental sweetlips [Plectorhinchus orientalis]

Wikipedia has no article on Oriental sweetlip.

Picture: Andaman&Nicobar Islands, India by Sami Salmenkivi

 

Orbicular batfish [Platax orbicularis]

The Orbicular Batfish (Platax orbicularis) is a popular aquarium fish endemic to tropical waters of the Indian and Pacific Oceans.

Its body is almost disc-shaped, and very thin; the tail, about 20% of the body length, is fan-shaped and taller than it is long. Males can grow to up to 50cm in length, though aquarium specimens are generally much shorter. In the wild, the Orbicular Batfish is found in brackish or marine waters, usually around reefs, at depths from 5 to 30 metres. Its range extends from the Red Sea and East Africa in the east to the Tuamotu Islands in French Polynesia in the west, and from southern Japan in the north to northern Australia and New Caledonia. It has been recorded off the coast of Florida, though this may be the result of dumping of aquarium specimens.

Juvenile fish are solitary or live in small groups, among mangroves or other inner sheltered lagoons. Adults are found in more open waters and at greater depth.

Wikipedia on batfishes: They are spade-shaped, laterally compressed, and very symmetrical triangular dorsal and anal fins. They are shiny silver with areas of yellow and vertical brown or black banding. The eyes are often located in one of the vertical bands as a method of camouflage. Scuba divers sometimes mistake them for angelfish, which are similar in shape but not closely related. Other genera in the family are characterized by long, trailing, pointed dorsal and anal fins.

Spadefish are generally considered to be an overfished group. Most of the individuals caught are small and young and are nowhere near the maximum size recorded for their species. A recent study in Current Biology (vol 16, p. 2434) has suggested that the batfish Platus pinnatus may play the role of a critical functional group in the Great Barrier Reef by eating seaweed that other herbivorous fish such as parrotfish and surgeonfish will not touch. Overgrowth of seaweed among corals occurs as a result of overfishing of large fish species and inhibits the ability of coral to support life.
Picture: Andaman&Nicobar Islands, India by Sami Salmenkivi

 

Honeycomb cowfish [Acanthostracion polygonius]

The honeycomb cowfish, Acanthostracion polygonius, belongs to the Ostraciidae family and is closely related to boxfish and trunkfish.

Picture: Andaman&Nicobar Islands, India by Sami Salmenkivi