This week’s Fish of the Week is a great catfish species for the slightly larger aquarium. The hoplo catfish (Megalechis thoracata) is a South American species that can grow up to 15cm. The name “hoplo” comes from a throwback to its original scientific description Hoplosternum. Hoplosternum derives from the Greek words hoplon meaning “weapon” and sternon for “chest”. The species was placed in a new genus in 1997 (Megalechis) to distinguish it from similar species that remain in Hoplosternum. Megalechis derives from the Greek mega “great” and lekis “plate”. This still refers to the large tough scales on the underside of the fish.