Morphology and molecular phylogeny of Hyalosynedra lanceolata sp. nov. and an extended description of Hyalosynedra (Bacillariophyta) Belando, Maria Dolores Jiménez Martínez, Juan Francisco Marín, Arnaldo Aboal, Marina The araphid diatom genus Hyalosynedra is a very common component of marine benthic communities, occurring as an epiphyte or colonizing hard substrata, and has a worldwide distribution. The hyaline appearance of the valve and the high striation density, which is indiscernible under a light microscope, makes the identification of most species difficult and very few studies have investigated their morphology, phylogeny or ecology in detail. In an extensive study of diatom communities from the hypersaline Mar Menor coastal lagoon (SE Spain), several new taxa were found. Herein we propose Hyalosynedra lanceolata sp. nov. based on morphological observations (light and electron microscopy) and molecular data (phylogenetic and sequence divergence analyses). The species has distinctive morphological characters (radiate colony, biseriate striation, lanceolate sternum and two long laminar lobed chloroplasts) that are new for the genus and have been included in a proposal to extend the genus description. Our results also show that H. toxoneides does not belong to Hyalosynedra, but appears to be more closely related to Thalassionema and Thalassiothrix. However, further molecular and morphological research is needed to clarify its taxonomic position. 2024-01-29T13:11:40Z 2024-01-29T13:11:40Z 2018-04-12 journal article Ma Dolores Belando, Juan F. Jiménez, Arnaldo Marín & Marina Aboal (2018) Morphology and molecular phylogeny of Hyalosynedra lanceolata sp. nov. and an extended description of Hyalosynedra (Bacillariophyta), European Journal of Phycology, 53:2, 208-218 https://hdl.handle.net/10481/87520 doi.org/10.1080/09670262.2018.1426787 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional European Journal of Phycology