I'd guess sessilifolia.
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I received d. Sessilifolia recently and i also grow burmanniies, by the look of the plant it looks like sessilifolia. Check out my recent thread of my plants for comparison.
What was the source of the plant, it would be better to ask the person which gave it to you to avoid confusion, specially if you inted to trade it this is very important for the person receiving the plants or seeds.
Good luck identifying the plant!
I feel it's a sessilifolia. If you observe closely in comparison, you may see that sessilifolia is more wedge shaped than burmannii. For burmannii, the part leaf that emerges from the central growth point is slightly rectangular, and from the middle to the tip is basically identical to sessilifolia.