Genus Monacoa

A genus comprising three species of small bioluminescent fishes with tubular dorsally-directed eyes, and a ventral “sole” - a large flattened area covered in large thin pigmented scales that functions as a large reflector organ controlling light emission.

The genus name Monacoa, resurrected from synonymy by Poulen et al. (2016), was constructed by Whitley (1943) without giving any etymological reason for the chosen name. However, the name may refer the state of Monaco in which the research expedition that sampled the two syntypes originated.
Author: Dianne J. Bray

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Cite this page as:
Dianne J. Bray, Monacoa in Fishes of Australia, accessed 14 Jun 2024,


Poulsen, J.Y., Sado, T., Hahn, C., Byrkjedal, I., Moku, M. & Miya, M. (2016) Preservation obscures pelagic deep-sea fish diversity: Doubling the number of sole-bearing opisthoproctids and resurrection of the genus Monacoa (Opisthoproctidae, Argentiniformes). PLOS ONE 11(8):e0159762 doi: 10.1371/journal.pone.0159762 

Whitley, G.P. 1943. Ichthyological notes and illustrations (part 2). Australian Zoologist 10: 167–187.