I was just wondering why poncirus/citrus hybrids always start their name with "citr...", like citrange, citrumelo, citrandarin.

Wouldn't it be much more logical if the name would start with "poncir..."? That would make it a "poncirange", "poncirumelo" or a "poncirandarin". Sounds strange maybe, but then it would be clear it's a poncirus hybrid...

Citrange, a cross between Poncirus trifoliata x Citrus sinensis, is a word created by Dr. Herbert John Weber in 1897. The actual word is a combination of the two words Citron and Orange. Early on Trifoliate Orange was also known by some, including Dr. Webber, as Citroncirus thus: = "Cit" from Citroncirus, and "range" from orange.

Ah OK, that explains it!
Thanks and happy holidays!

- Marc

I have a slightly different explanation.
The word 'citrange' was created when Poncirus trifoliata was botanically known as Citrus trifoliata. So the hybrid Citrus trifoliata x orange became commonly known as citrange.
However, botanically, Citrus x Poncirus should be called Citroncirus webberi, a name which is still sometimes used, to celebrate the creater of this hybrid.