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| Sideritis carpetana Izquierdo & Gavilán, in Izquierdo, Ugarte, Gutiérrez-Girón, Castro, Núñez et Gavilán, 2025. |
Abstract
A new species of Sideritis (Sideritis carpetana) is described from the calcareous, high-mountain Spanish flora in the central part of the Iberian Peninsula. It is found in a Mediterranean climate at high-elevation, perennial, calcareous grasslands, as well as in marble screes of anthropogenic origin in the Sierra de Guadarrama, Central System (Spain), in a reserve area within the Sierra de Guadarrama National Park, at 1996 m asl. Taxonomic morphological measurements were performed on collected specimens from Sierra de Guadarrama as well as on geographically-adjacent Sideritis (i.e., S. glacialis, S. pungens, S. hyssopifolia). The relationships among them were then explored with multivariate analysis. Sideritis carpetana is a dwarf shrub with an erect or decumbent habit, growing up to 15 cm; non-woody twigs with long hairs of 3–4 cells, leaves are entire, linear-oblanceolate, sparsely covered with trichomes; inflorescence is spiciform or slightly verticillated, flowers are yellow and nutlets ovoid. A key is supplied to help distinguish it from other high-mountain Iberian species included in section Sideritis. The species is unique in its combination of morphological and autoecological characters. S. carpetana shares similarities with S. glacialis, a species from Sierra Nevada, and its northern Mediterranean variant, S. glacialis subsp. fontqueriana from Sierra de Gúdar. They share morphological characters that are absent in other high-mountain Sideritis, reinforcing their Mediterranean character, as opposed to a more temperate or submediterranean character, such as those of the hyssopifolia group.
Key words: Calcareous high-mountain grasslands, Carpetan Mountains, high mountain species, marble outcrops, Mediterranean area, Sideritis sect. Sideritis, Sideritis subsect. Fruticulosa
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| Sideritis carpetana natural habit in the marble anthropogenic outcrops of La Flecha Pass (Sierra de Guadarrama National Park). |
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| Sideritis carpetana, Sierra de Guadarrama, La Flecha Pass (1996 m asl) a habit b Lower branches c inflorescence detail showing lower verticillaster bract and calyx d inflorescence detail showing upper verticillaster bract. |
Sideritis carpetana Izquierdo & Gavilán, sp. nov.
Jose Luis Izquierdo, Rosina Magaña Ugarte, Alba Gutiérrez-Girón, Concepción Obón de Castro, Diego Rivera Núñez and Rosario G. Gavilán. 2025. Sideritis carpetana (Labiatae), A New high-mountain Mediterranean Species from the marble outcrops of the Sierra de Guadarrama (Central System, Madrid, Segovia, Spain). PhytoKeys. 251: 143-159. DOI: doi.org/10.3897/phytokeys.251.129982
