Terapontidae
Terapontidae is a family of fish commonly known as grunts, terapon, or tarpon (not to be confused with the unrelated Tarpon, Megalops atlanticus). These fish are primarily found in the coastal waters of the Indo-Pacific region, with a few species extending into the Atlantic Ocean. They are typically found in brackish and freshwater environments, including estuaries, mangroves, and rivers.
Characteristics
Terapontids are characterized by their elongated, compressed bodies with a slightly rounded dorsal profile. They have a single dorsal fin with a distinct anterior spine followed by several soft rays. The anal fin is also spiny, and the tail fin is usually forked or rounded. Most species have a distinct lateral line that runs along the side of the body.
The family is diverse in size and coloration, with species ranging from small (less than 10 cm) to large (over 60 cm). Their coloration varies widely depending on the species, with some being plain silver, others with bright stripes or spots, and still others with elaborate patterns. Many species exhibit a change in color between juvenile and adult stages.
Environment
Terapontidae inhabit a variety of freshwater and brackish environments, including:
- Estuaries
- Mangrove swamps
- Rivers
- Coastal lagoons
- Marine environments
They are generally found in areas with abundant vegetation and muddy or sandy substrates. Many species are tolerant of varying salinity levels, making them adaptable to a wide range of habitats.
Feeding
Terapontids are primarily omnivorous, feeding on a variety of organisms, including:
- Insects
- Crustaceans
- Mollusks
- Small fish
- Algae
Some species are more specialized feeders, such as the Terapon jarbua, which primarily feeds on crustaceans. Many grunts also have strong pharyngeal teeth, which allow them to crush hard-shelled prey.
Reproduction
Terapontids are generally oviparous, releasing eggs that are pelagic (drifting in the water column) or demersal (resting on the bottom). Some species exhibit parental care, guarding their eggs or young. The breeding season varies depending on the species and geographical location.
Economic Importance
Terapontidae are important components of the food web in many ecosystems, serving as both predators and prey. Some species are commercially important food fish, while others are popular recreational catches. However, some species, particularly in freshwater habitats, are considered pests due to their ability to compete with other fish for resources.