Jorge
It could be 'Tina', it has leaves exactly like this, but then so do a lot of other crabs. You will never make a positive ID from the leaves alone. You need leaves, flowers, fruit, and growth habit. The fruit is exactly the same as M. sargentii, solid red, about 1/4 it 3/8 inch in diameter. Flowers are red quickly turning to white so any spray of flowers almost looks like a candy cane, it is quite distinctive. Growth habit is very low and shrubby. One of the smallest and slowest growing crabs. It may take several years for you to confirm all this.
Brent
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