A description of this new species was published by Samuel Pyke and Llorenç Sáez in 2016 in the journal Willdenowia based on samples collected at Portell de Caro (Roquetes).
This grass is found in the Ports de Beseit and nearby mountains and has intermediate characters between other members of the same genus from the area; however, it has the peculiarity of having a different chromosome number (2n = 70).
As the original description in the publication states, the holotype of this new species was deposited in the BC Herbarium and a duplicate (isotype) in the Jaca Herbarium. In addition, drawings of transversal sections of the leaves of the specimen preserved in the BC Herbarium are included in the publication.
Festuca dertosensis Pyke & L. Sáez
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