Melamphaes Poromitra Scopeloberyx Scopelogadus Sio Ridgeheads, also known as bigscales, are a family (Melamphaidae, from the Greek melanos [black] and amphi [by both sides]) of small, deep-sea stephanoberyciform fish.

The head is large and scaleless, with its profile either bluntly rounded or with a sharp frontal angle; it is conspicuous for its prominent ridges, which are covered by thin skin.

The lateral line (excluding the network of cranial canals) is largely absent; when present, it is reduced to 1–2 pored scales following the operculum's upper edge.

The largest species recorded is Poromitra curilensis, a Pacific ridgehead related to the crested bigscale,[1] at up to 18 centimetres standard length (SL; a measurement excluding the caudal fin).

There is also a marked segregation of life stages: larval and juvenile ridgeheads are present within the upper 200 metres of the water column, whereas adults are typically found much farther down.

The family is sometimes termed pseudoceanic because, rather than having an even distribution in open water, ridgeheads occur in significantly higher abundances around structural oases, notably seamounts and over continental slopes.