Any gravitons regularly missing trees? (6)

I believe the answer is:

ngaios

I'm a little stuck... Click here to teach me more about this clue!

'missing trees?' is the definition.
'ngaios' can be an answer for 'trees?' (I've seen this before). I'm not certain of the 'missing' bit.

'any gravitons regularly' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'any'+'gravitons'='anygravitons'
The alternating letters of 'anygravitons' are 'NGAIOS'.

Can you help me to learn more?

(Other definitions for ngaios that I've seen before include "New Zealand trees" , "Southern Hemisphere trees" .)

I've seen this clue in The Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.