Lactarius lactarius
(False trevally )
(False trevally )
Kingdom: Animalia
Phylum: Chordata
Sub phylum : Vertebrata
Class: Actinopterygii
The false trevally (Lactarius lactarius) is a species of fish in the family Lactariidae, currently the sole member of the family. False Trevally, a silvery-blue false trevally fading to silvery-white below with a dusky blotch on the upper part of the gill cover and yellowish fins.
Identifying Features
Body Shape:
The false trevally has a compressed, elongated, and oval-shaped body. The body is somewhat deep and laterally flattened.
Coloration:
The body is typically silvery-white or pale in color. The fins may have a yellowish tint, particularly the pectoral fins.
Juveniles often display vertical bars on their sides, which may fade as they mature.
Head and Mouth:
The head is relatively small, with a pointed snout. The mouth is terminal, located at the front of the head, and is slightly oblique.
The eyes are moderately large.
Fins:
The dorsal fin is continuous, with the anterior part consisting of spines and the posterior part with soft rays.
The anal fin is relatively short, with a similar structure to the dorsal fin.
Pectoral fins are long and often pointed, while the pelvic fins are shorter.
Unique Features
Lactating Glandular Structures:
The false trevally has specialized glandular structures that secrete a milky substance, possibly as a defense mechanism, which is quite unique among fish.
Scales:
The scales are small, smooth, and easily detached, giving the fish a slippery feel.
Forked Caudal Fin:
The caudal fin is deeply forked, which aids in fast swimming.
Morphology
Size:
False trevally typically reaches a length of about 20-30 cm, though it can grow larger in favorable conditions.
Body Proportions:
The body is about 2-3 times as long as it is deep, and the head is about 4-5 times in total body length.
Teeth:
Teeth are small and pointed, arranged in bands on the jaws.
Reproduction
Spawning:
False trevally is believed to spawn in shallow waters, with eggs and larvae being pelagic (free-floating) in nature.
Sexual Maturity:
The fish reaches sexual maturity relatively early, which is an adaptation to its environment where predation pressure might be high.
Breeding Season:
Typically, breeding occurs during warmer months, though specific times may vary depending on the geographical location.
Habitat
Geographical Distribution:
Found across the Indo-Pacific region, from the eastern coast of Africa to Southeast Asia, and even as far as northern Australia.
Preferred Environment:
False trevally favors coastal environments, often residing in estuaries, lagoons, and shallow bays.
They are commonly found over sandy or muddy substrates where they can search for food.
They can tolerate a range of salinities, which is why they are frequently found in estuarine environments.
Diet:
These fish are omnivorous, feeding on small invertebrates like crustaceans, mollusks, and sometimes plant material or detritus.
Ecological Role
Trophic Level:
As an omnivorous species, false trevally plays a role in both predator and prey dynamics within its ecosystem. It helps control populations of smaller invertebrates and serves as prey for larger fish and marine birds.