Matted Filefish Care Guide
Acreichthys tomentosus · Saltwater Filefish
What Matted Filefish look like
The Matted Filefish, Acreichthys tomentosus, exhibits a distinctive and robust body shape, reaching a maximum adult size of approximately 6 inches (15 cm). Its morphology is characterized by a flattened, elongated body covered with small, rough scales that give it a textured appearance. The coloration is typically a mottled blend of brown, green, and yellow hues, providing effective camouflage against its natural habitat. Sexual dimorphism is subtle, with males often displaying slightly more vibrant coloration during breeding periods. Notable defensive adaptations include the ability to change color and texture to blend into its surroundings, as well as the presence of a dorsal fin that can be raised to create a more formidable silhouette. The species also possesses a unique set of teeth that are fused into a beak-like structure, which aids in its feeding habits.
Behavior & temperament
Acreichthys tomentosus is generally a solitary fish, though it may be observed in small groups in areas with abundant food sources. It typically inhabits shallow reef environments, often found at depths of 3 to 30 meters. The species exhibits a relatively calm temperament but can display territorial behavior when defending its feeding grounds. Breeding behavior involves courtship displays where males may exhibit brighter colors and engage in intricate swimming patterns to attract females. During the breeding season, males may become more aggressive towards other males. The fish primarily feeds during daylight hours, foraging among the substrate and coral for food.
Diet & feeding
The Matted Filefish is primarily herbivorous, feeding on algae and small invertebrates found on the reef. In captivity, it requires a varied diet that includes high-quality marine algae, spirulina, and occasional protein sources such as brine shrimp or mysis shrimp.
Behind the name
The genus name 'Acreichthys' derives from the Greek words 'akra' meaning 'point' and 'ichthys' meaning 'fish', while the species name 'tomentosus' comes from the Latin word for 'matted' or 'tangled', referring to its appearance.
Plan your tank
Check the numbers before you buy: tank volume, salinity, salt mix, water changes, and your ongoing care routine.
Keeping Matted Filefish?
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