- Plotosus lineatus, commonly known as the striped eel catfish, is a small to medium-sized marine catfish belonging to the family Plotosidae.
- It is native to the Indo-Pacific region, ranging from the eastern coast of Africa and the Red Sea through Southeast Asia to northern Australia and parts of the western Pacific.
- Adults typically inhabit coral reefs, rocky substrates, and sandy lagoons, while juveniles often form dense, highly coordinated schools in shallow coastal waters. Its distinctive appearance and venomous spines make it both fascinating and potentially dangerous to humans.
- Morphologically, Plotosus lineatus is easily recognized by its elongated, eel-like body and a pattern of narrow, creamy-white longitudinal stripes running along a dark brown to black background. Adults can reach lengths of about 30–35 cm, though most are smaller. The head bears several pairs of sensitive barbels—one of the species’ hallmark features—which help detect prey in murky waters or at night. Like other catfishes, it possesses strong, sharp spines on the dorsal and pectoral fins. These spines are connected to venom glands capable of delivering a painful sting, which serves as an effective defense mechanism against predators.
- The species exhibits notable changes in social behavior as it matures. Juveniles, often less than 10 cm long, are famous for forming tight, moving spheres or balls consisting of dozens to hundreds of individuals. This schooling behavior is thought to deter predators and improve foraging efficiency. As they grow older, the fish become more solitary or form small, loose groups, spending more time near the substrate and hiding in crevices during the day.
- Plotosus lineatus is an opportunistic omnivore, feeding primarily on benthic invertebrates such as crustaceans, mollusks, and worms, as well as small fishes and organic detritus. Foraging typically occurs at night, when individuals leave their shelter to scour the sea floor using their barbels to locate prey. In turn, they are preyed upon by larger predatory fishes, but their venomous spines significantly reduce predation risk.
- In recent years, Plotosus lineatus has also been recorded as an invasive species in parts of the Mediterranean Sea, likely introduced through the Suez Canal in a phenomenon known as Lessepsian migration. In these new environments, it has established stable populations and is considered ecologically significant due to its venomous nature and potential impacts on native benthic communities. For humans, stings from this species can cause intense pain, swelling, and, in some cases, systemic symptoms; thus, it is advised to exercise caution when handling or encountering them in the wild.
- Overall, Plotosus lineatus is a striking example of a marine fish that combines unique morphology, complex behavior, and ecological adaptability. Its life history—from the coordinated schooling of juveniles to the solitary foraging of adults—reflects a dynamic balance between defense, feeding strategy, and environmental adaptation. However, its invasive potential and venomous capability also highlight the need for awareness and careful management in both its native and introduced ranges.
