Nyssaceae · 2n = 42
2n = 42
Family Nyssaceae. Somatic 2n = 42 in Camptotheca, Davidia, and Diplopanax.
PhotoMyrabellaCC BY-SA 4.0
Oginuma and Tobe 2021 report 2n = 42 in Camptotheca, Davidia, and Diplopanax, after setting dubious historical counts aside. Sister genera sit at 2n = 44 (Nyssa) and 2n = 26 (Mastixia). They read 2n = 42 as six sets of seven: hexaploid, basic number x = 7.
What it supports
Davidia is the dove tree. Nyssa, beside it in the family, is the tupelo. A person can tell the trees apart, and the chromosomes already disagree. The hexaploid reading, six sets of seven, is the authors'. Wheat and oat are a different family.
What it does not
Not every historical count. Not wheat. Not oat. Not three genus cards. Not Adams. Camptothecin is a story about a chemical. It is not this chromosome count.
ExactnessExact
Form42
Unitchromosomes
Strengthhard
When2021
Hung24 September 2026