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A new species of spikemoss, Selaginella densiciliata in S. subg. Heterostachys sect. Tetragonostachyae, China, is described from southeastern Xizang, based on morphological and molecular phylogenetic data. Morphologically, S. densiciliata is similar to S. repanda, S. subvaginata and S. vaginata, but the new species can be easily distinguished from them by having sterile leaves margins densely ciliate, symmetrical axillary leaves oblong ovate to ovate-triangular, and ovate dorsal leaves obviously carinate. Molecular phylogenetic analysis resolves S. densiciliata as sister to the clade comprised with S. vaginata and S. xipholepis, which confirms the recognition of the new species. [ABSTRACT FROM AUTHOR]

Eclogites characterized by a garnet + clinopyroxene + orthopyroxene + sanidine + rutile assemblage are reported for the first time in the eastern Bangong suture, central Tibet (China). Garnet and sanidine are exsolved from clinopyroxene. Al-exchange barometer for orthopyroxene and garnet and K concentrations in clinopyroxene indicate a peak pressure of ∼4 GPa. The occurrence of these ultrahigh-pressure rocks implies the subduction of continental crust to a depth of >130 km along the eastern Bangong suture zone during the Early Jurassic. The denudation of these ultrahigh-pressure metamorphic rocks could have provided a significant source for the Jurassic turbidites in the western Bangong ocean basin. [ABSTRACT FROM AUTHOR]