Fish o’ the day | Blackfoot Lionfish

Posted by gerard on January 27, 2009 under Saltwater Fish | Be the First to Comment

Parapterois is a genus of lionfish, a group of venomous fish in the scorpionfish family. There are two species, P. heterura and P. macrura. P. heterura is occasionally known as the blackfoot lionfish. The other species, P. macrura, is poorly known; this fish has only been mentioned in a handful of scientific papers and has remained obscure. These fish originate from marine environments in the Indian Ocean or near it. These venomous fish are occasionally seen as aquarium fish.

Anatomy and appearance

Parapterois heterura resting on the substrateParapterois is similar to the other lionfish in appearance. Their bodies are red and white, and their pectoral fins are expanded. These fish are venomous. P. heterura may reach a maximum of about 23 centimetres (9 in) TL. However, most specimens are much smaller; larger adults of both species are about 11 centimetres (4 in) in length.

A number of differences set this genus apart from Pterois, in which P. heterura was first described to. Parapterois have more (18-21) pectoral fin rays than Pterois (12-17), and, in the former, these rays may be branched, while they are never branched in Pterois. Parapterois have two anal fin spines, while Pterois have three. Also, as a more obvious trait, the caudal fin of these fish are truncated with longer upper and lower caudal fin rays, while the caudal fin in Pterois is rounded.

P. macrura and P. heterura differ in that P. heterura has scales in a pit between the posterior nostrils while P. macrura does not (except for a population of P. heterura found off the coasts of West India, South Africa, and Mozambique, which may be a different species). These species do not differ much in fin spine, fin ray, gill raker counts, and most body proportions. Their differences lie in a small difference in head proportions. Also, in adults, the upper margin of the eye of P. heterura is below the base of the first dorsal fin spine, while it is above in P. macrura (this trait is not consistent in juveniles, in which the eye margin may be below in both species).

Distribution and habitat
Parapterois originate from the Indian Ocean and the West Pacific Ocean. P. heterura is widely distributed on the southeastern coast of Africa as well as off Japan and in Indonesia. By contrast, P. macrura is only found off the west coast of India.

P. heterura may usually be found in sheltered coastal bays with a soft bottom, such as fine sand or mud. It’s found in depths ranging from 40-300 metres (130-1000 ft).

Ecology

Parapterois heterura showing the inner surface of its pectoral fins.Parapterois are sedentary fish. P. heterura may even bury itself within the substrate.P. heterura flashes its brightly-colored pectoral fins to startle predators and escape, but it may also use these fins to corner prey. This behavior has been demonstrated in other lionfish.

In the aquarium
Despite the popularity of other lionfish, Parapterois species are only rarely found in the aquarium trade. P. heterura can be found on certain online marine aquarium fish stores, but is not common.

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Text is available under the terms of the GNU Free Documentation License.

Fish o’ the day | Lionfish

Posted by gerard on October 15, 2008 under Saltwater Fish | Be the First to Comment

Lionfish is any of several species of venomous marine fish in the genera Pterois,  Parapterois, Brachypterois, Ebosia or Dendrochirus, of the family Scorpaenidae. The lionfish is also known as the Turkey Fish, Dragon Fish or Scorpion Fish.  They are notable for their extremely long and separated spines, and have a generally striped appearance, red, brown, orange, yellow, black, maroon, or white.

Native environment

The lionfish is native to the tropical Indo-Pacific region of the world, but various species can be found worldwide. Due to a recent introduction, the lionfish has recently been spotted in the warmer coral regions of the Eastern Atlantic Ocean and Caribbean Sea.  Lionfish are an invasive species in the Atlantic Ocean and the Caribbean Sea regions.  Successful breeding of the lionfish in captivity has not been looked upon.

Size

The common lionfish generally reaches a size of 30-35cm. Smaller lionfish (e.g., the Fuzzy Dwarf) are typically the size of a tennis ball (not including fins). There are many types of lionfish that vary in size. The lionfish has been one of the most venomous fish in the ocean bottom floor.

Venom

Lionfish have venomous spines that are deadly to their prey, but usually not to humans (though the venom is used purely for defense, not attack). If a human is envenomed, that person will experience severe pain and possible headaches and vomiting. A common treatment is soaking the afflicted area in hot water, as very few hospitals carry specific treatments.  However, immediate emergency medical treatment is still advised, as some people may be more susceptible to the venom than others.

Feeding

Lionfish are voracious predators. When hunting, they corner prey using their large fins and then use their quick reflexes to swallow the prey whole. In captivity, lionfish can be trained to eat frozen brine shrimp, mysis, and krill.

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Text is available under the terms of the GNU Free Documentation License.