Tortula murciana (Pottiaceae, Bryophyta), a New Species from Mediterranean Mountains

The genus <i>Tortula</i> is one of the most diverse and morphologically complex groups within Pottiaceae. This study presents both morphological and phylogenetic evidence for the recognition of a new species, <i>T. murciana</i>, within the <i>T. subulata</i> complex. The new species is distinguished by a unique combination of traits, including a translucent leaf lamina, upper laminal cells with 3-7 simple, wart-like papillae (verrucae), and middle laminal cells 16-24(35) µm wide, that are much higher near the costa than at the leaf margins. The ventral epidermal cells of the costa at mid-leaf are quadrate to spherical and inflated. The costa is robust, up to 140 µm wide at mid-leaf and papillose on the dorsal side. The apical cell of the apiculus is typically hyaline and often deciduous. The leaf border is usually absent or poorly developed. The basal membrane of the peristome is 0.70-0.90 mm long, with a reticulate pattern where the lumina are delimited by strongly developed muri ornamented with globose clusters of ear-like lobes (auricles). Phylogenetic analysis of the nuclear ITS region places <i>T. murciana</i> within the <i>T. subulata</i> complex, clearly distinguishing it from <i>T. mucronifolia</i> and <i>T. subulata</i> var. <i>graeffii</i>, with which it shares the closest morphological similarity. Although most specimens can be identified morphologically, some remain difficult to name, making them a semi-cryptic species. The new species is formally diagnosed, described, illustrated, and compared to similar taxa. A key to all species in the complex is also provided.