Do not worry, I believe Couma seedling will develop well. A friend planted some seeds Couma and also informing me about this development. Are species that I never planted, so it is important to know the difficulties we can propagate these rare species.
Keep us informed.
Dear Vitor, I really hope it will survive. I frear that the zone where the cotyledons are attached got bad (see the brown color). My wife said the seedling is still weak. I told to use some fungicide for security, although I prefer to void any chemicals. Eugenia longiracemosa is the first forming a seed. Till now conly Couma, Tetragastrid and the Eugenias sprouted, but Tetragastris seems still to be busy with the root.
It makes logic, as the rest of the seed You gave me mostly take time.
Have no experience with Duguetias, but I have a very good experience with Annona cherimola and always late but 99% germination.
Older seeds always take some months of time but still sprout.
Once I germinated n Annona after 3 years and an accidental washing mashine treatment
Intresting if Duguetias are more difficult to germinate ?!
With what I had always problems was Garcinia mangostana, so now I'll see how I do with other Garcinias.
Garcinia mangostana, Nephelium lappaceum and Calligonum aphyllum are my cursed plants, many times I tried I always failed.
Nephelium always forms a root and then dies, while its cousins (Dimocarpus longana and Litchi chinensis do very well).