LIONFISH: CHARACTERISTICS, HABITAT, REPRODUCTION, STING, TREATMENT - BIOLOGY - 2024

The lionfish (Pterois antennata) is a poisonous species that is part of the Scorpaenidae family. It is characterized by the long tentacles that protrude from behind each of its eyes and by the stripes on the pectoral fins. In addition, its body is covered by lines, where the colors white, red and brown alternate.

Regarding its distribution, it is located in the waters of the Indian and western Pacific oceans. Pterois antennata lives mainly on coral reefs, where it swims slowly, waving its dorsal and anal fins.

Lion fish. Source: Nhobgood Nick Hobgood

This species communicates through visual cues. For example, if a male, while looking for his food, meets another male, his body becomes darker. In addition, its poisonous dorsal fins are pointed towards this.

characteristics

Lionfish have a laterally compressed body, which can be about 20 centimeters long. Regarding the fins, the first dorsal has between 12 and 13 spines, while the second is made up of 11 or 12 soft rays. These rays lack tissues that connect them.

The anal fin contains 3 spines, after which are 6 soft anal rays. As for the pectoral fin, it has 17 non-branched soft rays. These are long and are joined halfway by a membranous tissue.

Pterois antennata has a poisonous glandular tissue, where toxins are produced. These glands are found at the bases of the dorsal, pelvic, and anal spines.

Teeth

This species has very numerous teeth. They are small in size and form dense groups, both on the upper and lower jaw. Functionally, these teeth appear to be limited to grabbing the prey that the fish captures.

Coloration

The coloration of this species presents variations, however, between the male and the female there are no differences. Generally, the fish is reddish to tan in color, with dark vertical stripes. These are wide on the body, while towards the area of ​​the caudal peduncle they become oblique and narrow.

On the head it has three bars of a dark brown hue, including a sloping line across the corner of the eye. As for the interradial membranes of the pectoral fins, they have numerous dark spots.

In addition, the lionfish has a particular bright white spot, located at the back of the base of the pectoral fin. From the top of each eye, a long tentacle sprouts. This has light and dark bands.

Sexual dimorphism

In Pterois antennata, the difference between the sexes is not very obvious. However, the male has a larger head than the female. Also, the caudal peduncle is longer in the male than in the female.

Another aspect that identifies the male is that it has 6 to 10 bands on the pectoral fins, while the female is characterized by having between 4 and 6.

Predators

The lionfish has several adaptations that serve as a defense mechanism. Thus, it avoids stalking and attack by predators. Among these are its aposematic coloration and poison, which it inoculates through its spines.

However, some species are considered its natural predators. Some of these are the painted cornet fish (Fistularia commersonii), the Caribbean reef shark (Carcharhinus perezii), the whitetip reef shark (Triaenodon obesus) and the blacktip reef shark (Carcharhinus melanopterus).

Behavior

The lionfish is a nocturnal animal. During the early hours of the night, it goes out to hunt its prey, remaining active until the first rays of daylight. At that moment, they go to their refuge, located among the rocks and corals.

While he is resting, he remains almost motionless, with his head tilted down. In this way, the poisonous spines point towards the entrance of the crevice. Thus, it protects itself from any predator that tries to capture it.

Most of his life he is a solitary animal. However, when he is in the youth stage, he can form small congregations. Likewise, in the reproductive season it usually forms temporary pairs.

Habitat and distribution

Pterois antennata is widely distributed throughout the western Indo-Pacific. Thus, it ranges from French Polynesia to East Africa and South Africa. Also, it extends to South Australia and Japan. However, this species is absent from the island of Hawaii.

Lionfish inhabit marine lagoons and rocky and coral reefs, which are up to 50 meters deep. The animal does not stray far from these areas, as during the day it tends to take refuge in caves, rocky outcrops, crevices and under corals.

In relation to the range of home, it covers several square meters. Because it is a highly territorial fish, they fiercely defend their space against their congeners, using their poisonous spines for this.

Reproduction

Pterois antennata is a solitary animal, but during spawning it forms aggregations. Before mating, the male becomes darker and uniform in color, as the stripes become less apparent.

In the case of females, when the eggs are mature, they turn paler. In this sense, the belly area, pharynx, and mouth turn silvery-white.

Breeding males are aggressive, especially when another male invades their territory to woo the female. In this case, the male approaches the intruder, head pointing downward. Thus, it threatens it with its poisonous spines.

If this does not deter the defiant male, the attacker shakes his head, attempting to bite him.

Mating

After the male dominates the territory, the courtship begins, which almost always occurs at dusk. First, it surrounds the female and then rises to the surface, followed by the female. Both can descend and ascend several times before spawning.

During the final ascent, the pair swim just below the surface of the water. At that time, the female releases egg masses, consisting of up to 15,000 eggs. This agglomeration is made up of 2 hollow tubes of mucus, which float under the surface of the water.

After 15 minutes, the tubes absorb seawater, turning into oval balls, measuring 2 to 5 centimeters in diameter. As the female releases the eggs, the male releases the sperm. This fluid penetrates the mucus masses, thus fertilizing the ovules.

Development of the embryo

In this species, the formation of the embryos is evident 12 hours after fertilization. At 6 pm, the head and eyes can be seen. Finally, at 36 hours the larvae hatch. These are planktonic, investing much of the energy in their development. By the fourth day, the larvae can swim and feed on small ciliates.

Feeding

The Pterois antennata is an important predator in the diverse ecosystems that surround the coral reefs. Their diet is based on crustaceans, among which are crabs and shrimp. However, it also eats other marine invertebrates and small fish, including the young of its own species.

Consumed species include red snapper (Lutjanus campechanus), coral trout (Plectropomus leopardus), and banded coral shrimp (Stenopus hispidus).

The lionfish usually consume an average of 8.2 times the equivalent of its body weight annually, which can correspond to 45 kilograms of prey. Daily, the juvenile eats 5.5 to 13.5 grams, while the adult ingests an average of 14.6 grams.

Hunting method

This animal hides during the day, between crevices and rocks, while at night it goes out in search of its food. He is an expert hunter, able to use the specialized muscles of his swim bladder to exert precise control of his position within the water column. Thus, by adjusting the center of gravity, it can attack its prey more efficiently.

When stalking the animal, it lifts its pectoral fins protectively. This screen, in conjunction with their body coloration, reduces the possibility of being seen.

In addition, it can be camouflaged with the environment, where irregular branches of coral and the spines of sea urchins stand out. In this way, going unnoticed, the lionfish makes a quick movement and attacks the prey, capturing it with its fine teeth.

In this video you can see how a specimen of this species feeds:

Sting and treatment

The poisonous nature of Pterois antennata can constitute a health emergency. A bite from this fish could cause very painful wounds. This is sharp, intense and sharp, and is felt most strongly at the site where the thorns are stuck.

Other symptoms include tingling, sweating, and blisters on the wound. In the most severe cases, there may be systemic repercussions.

Thus, the injured person experiences headache, vomiting, nausea, abdominal pain, seizures and delusions. Also, you may have paralysis of the extremities, shortness of breath, increased or decreased blood pressure, muscle weakness, and tremors.

In severe cases, heart complications, pulmonary edema, and loss of consciousness occur. The appearance of these symptoms will depend on the amount of poison inoculated and the health of the affected person.

Treatment

Experts recommend that injuries should be treated in a medical center. However, while arriving at the site, several actions can be taken.

Regarding the basic treatment, first, the wound must be cleaned, removing any remaining spine. Subsequently, it is important to immerse the affected area in hot water, at a temperature of approximately 45 ° C.

This is because studies in other species of the genus Pterois have shown that high temperature heat treatment suppresses the gelatinolytic and hemolytic activities of the toxic substance.

References

1. Steer, P. (2012). Pterois antennata. Animal Diversity Web. Recovered from animaldiversity.org.
2. Wikipedia (2020). Spotfin lionfish. Recovered from en.wikipedia.org.
3. Dianne J. Bray (2020). Pterois antennata. Fishes of Australia. Recovered from fishesofaustralia.net.au.
4. Motomura, H., Matsuura, K. (2016). Pterois antennata. The IUCN Red List of Threatened Species 2016. Retrieved from org.
5. ITIS (2020). Pterois antennata. Recovered from itis.gov.
6. Manso, Lenia, Ros, Uris, Valdés-García, Gilberto, Alonso del Rivero, Maday, Lanio, María, Alvarez, Carlos. (2015). Proteolytic and hemolytic activity in the venom of the lionfish Pterois volitans, an invasive species of Cuban sea coasts. Recovered from researchgate.net.
7. Discover Life (2020). Pterois antennata. Recovered from discoverlife.org