Is it lime?
LOL! No, not lime. But that is a good one. I save the limes for my Coronas, which I am still hooked on from living in Sandy Eggo. It is not a smell so much as a pungent zing to the fresh flowers. Bursting trichomes? A nasal THC meter? It is not the same as the indica stench, which I also love.
I've grown several Brazilians, including an IBL, that all have a prominent lime scent and taste. DrZiggy posted this description of Pondo Mystic that pretty closely describes it.
smells like fresh zingy citrus, more like sour lime than lemon and has a sharp, spicy zing on the flavour too combined with an earthy undertone. It emits a very focused and clear high."
That's a perfect description of Utopia Haze (Brazilian IBL).
Man, I want some of that! Brazilian is one landrace that I have never seen here in the west. I do not know why, but Brazilian weed was never imported into California that I was aware of. We had gobs of Colombian, Panamanian, Thai, Afghan/Lebanon/Israel/Morocco hash, Cambodian, Mexican, African, Nepalese, Hawaiian, and some Indian ganja, Peruvian and Jamaican, and of course local 'homegrown', but never Brazilian. I have read that the original Brazilian landraces are very old, as old as the Chilean ones dating back to the 1500s, and they were grown pretty exclusively for the local markets. I have read that they are good, but never saw any for sale or smoked any, ever. Supposedly like in the Caribbean, the Brazilian seeds were sourced from Africa with the early slave trade days, though Portuguese shipping could have brought the hemp seeds to Brazil from anywhere around the world as early as the 16th century. 500 years ago!
Supposedly the later 1970s "landraces" in Brazil are from imported sativa landrace varieties, likely from the Caribbean, Central America and Colombia. The data and information is rather spotty though. I speak and read Spanish, but not Portuguese.