Analysis of stable oxygen isotope composition of otoliths has shown that Monomitopus pallidus and Monomitopus kumae undergo an ontogenetic habitat shift, spending their early life pelagically in shallower waters, before descending to the deep-sea floor where they stay for rest of their lives.[3] The larvae of these species have been reported to coil tightly and drift in the pelagic until settlement.[4] A subset of species have been found to have a bilaterally paired hole or fenestra in the skull.[5]
Species
There are currently 14 recognized species in this genus:
^ abChang, N. N.; Liu, E. Y.; Liao, Y. C.; Shiao, J. C. (2015). "Vertical habitat shift of viviparous and oviparous deep-sea cusk eels revealed by otolith microstructure and stable-isotope composition". Journal of Fish Biology. 86 (2): 845–853. doi:10.1111/jfb.12605. PMID25613184.