Actinopteri (ray-finned fishes) > Saccopharyngiformes
(Swallowers and gulpers) > Monognathidae
Etymology: Monognathus: Greek, monos = one + Greek, gnathos = jaw (Ref. 45335); boehlkei: Named for the late James E. Böhlke in recognition of his valuable contributions to the study of apodal fishes. More on authors: Bertelsen & Nielsen.
Environment: milieu / climate zone / depth range / distribution range
Marine; bathypelagic; depth range 2500 - 5430 m (Ref. 34506), usually - m (Ref. ). Deep-water; 0°C -
Atlantic Ocean: the holotype was caught near Bermuda and the paratypes southwest of Madeira.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 7.0 cm TL male/unsexed; (Ref. 34506)
Morphology | Morphometrics
soft rays: 110 - 130. M. boehlkei differs from all other species of the genus by the high number of anal fin rays (110-130 vs. 42-88) and by an obtuse angle between rostral fang and frontal profile of skull. It is further distinguished by the following combination of characters: head short, snout blunt, skull length4.2-5.2% TL, rostral fang with dorsal profile slightly concave, anal fin origin below dorsal fin rays number 7-13, pectoral fin 2-3% TL, lower jaw nearly straight, and 6 lateral, subdermal spots of pigmentation (Ref. 34506).
All specimens were taken in closing nets, one between 2500 and 3500 m with a bottom depth of 4563 m and the other specimens between 10-3- m above the bottom with soundings from 2960-5430 m (Ref. 34506).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Bertelsen, E. and J.G. Nielsen, 1987. The deep sea eel family Monognathidae (Pisces, Anguilliformes). Steenstrupia, 13(4):141-198. (Ref. 34506)
IUCN Red List Status (Ref. 124695)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 115969
): 2.5 - 2.9, mean 2.7 °C (based on 105 cells).
Phylogenetic diversity index (Ref. 82805
= 0.5001 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00102 (0.00046 - 0.00225), b=3.06 (2.88 - 3.24), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.6 ±0.59 se; based on food items.
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .