Public index · Biology
Mesoplodon · 2n = 42
2n = 42
Beaked-whale genus Mesoplodon. Diploid karyotype 2n = 42 in the species these papers counted.
Mesoplodon is one of the few cetacean genera with diploid number 2n = 42. Árnason 1978 counted 2n = 42 in M. europaeus and M. carlhubbsi. Kurihara et al. 2017 counted 2n = 42 in M. stejnegeri and M. carlhubbsi. Most Cetacea remain 2n = 44.
What it supports
A measured diploid number, repeated across species, with a fusion reading from the general cetacean 2n = 44 karyotype. Both papers describe a huge X chromosome loaded with C-heterochromatin. Kurihara calls it a huge subtelocentric X.
What it does not
Not every Mesoplodon species. Not the sperm whale or the pygmy sperm whale. Not Ziphius, and not the baleen whales, on this card. Not Adams. M. densirostris is a later count. These two papers do not report it.
ExactnessExact
Form42
Unitchromosomes
Strengthhard
When1978
Hung24 September 2026