Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Osmeriformes
(Smelts) > Opisthoproctidae
(Barreleyes or spookfishes)
Etymology: Monacoa: The name constructed by Whitley was without any etymological reason; however, it is likely referring to the state of Monaco, in which the research expedition that sampled the two syntypes originated.; griseus: Name from Latin 'griseus' for 'grey'; referring to the uniform greyish anterior part of the sole lacking distinct patterns of pigmentation.
Environment: milieu / climate zone / depth range / distribution range
Marine; bathypelagic; depth range 0 - 521 m (Ref. 111070). Deep-water
Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri
Southwest Pacific: New Zealand and possibly Australia.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 6.4 cm SL male/unsexed; (Ref. 111070)
Morphology | Morphometrics
This species is distinguished by the following characters: a greyish anterior part of the sole, abruptly changing just in front of the pelvic fins, to a dense pigmented posterior part; two adult specimens show in addition, a relatively weak irregular large blotch just in front of the change in pigmentation, centered approximately below the anterior part of the dorsal fin in the vertical plane; scale pockets possibly relatively light (Ref. 111070).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Poulsen, J.Y., T. Sado, C. Hahn, I. Byrkjedal, M. Moku and M. Miya, 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):1-23. (Ref. 111070)
IUCN Red List Status (Ref. 120744)
CITES (Ref. 118484)
Threat to humans
CountriesFAO areasEcosystemsOccurrencesIntroductionsStocksEcologyDietFood itemsFood consumptionRation
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01995 (0.00906 - 0.04395), b=3.01 (2.83 - 3.19), in cm Total Length, based on all LWR estimates for this body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.4 ±0.1 se; Based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low vulnerability (15 of 100) .