Monacoa grimaldii

Monacoa grimaldii is a species of fish in the family Opisthoproctidae, the barreleyed fish or spookfish. It has a body length of 8 cm (3.1 in) SL.^[2]

Mirrorbelly
Fresh specimen
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Argentiniformes
Family:	Opisthoproctidae
Genus:	Monacoa
Species:	M. grimaldii
Binomial name
Monacoa grimaldii (Zugmayer, 1911)
Synonyms
Opisthoproctus grimaldii Zugmayer, 1911

Taxonomy

The species was included in the genus Opisthoproctus from its description in 1911 until a 2016 review was made using fresh specimens, which found that "O." grimaldii is too distinct to be grouped with O. soleatus (the type species of Opisthoproctus); along with two newly recognized species, this species of barreleye was moved to the resurrected genus Monacoa, coined by Whitley in 1943. However, the genus Monacoa is still the sister genus to Opisthoproctus, sharing the same flat belly covered by enlarged scales (the "sole").^[3][4]

Common names

Monacoa grimaldii has been referred to as the mirrorbelly spookfish,^[5] mirrorbelly, flatiron fish, Grimaldi's barreleye, or simply barreleye.^[1][2]

Habitat and distribution

The species is typically mesopelagic, but it has been recorded from depths of 0 to 4,750 metres (0 to 15,584 ft). Sources disagree on its exact distribution. According to Poulsen and colleagues, M. grimaldii is known with certainty only from the Atlantic Ocean, with records from the Pacific Ocean representing other species of Monacoa.^[3] However, FishBase and Catalog of Fishes includes specimens caught in the Pacific, and in CoF's case, the Indian Ocean as well.^[6][2]