The northern Portuguese coast is a biogeographic transition zone where many macroalgal species have their distribution limits; it is thus a particularly interesting region for investigating species distribution shifts. An updated and complete list of species for this region is not available in spite of its baseline importance for comparative studies with past and present data. Based on new records, literature references, and herbarium data, we provide an updated checklist of the benthic marine algae of the northern Portuguese coast. This checklist includes 346 species: 26 Cyanobacteria, 200 Rhodophyta, 70 Ochrophyta, and 50 Chlorophyta. From these, 21 species are new records for the Portuguese coast (Lyngbya aestuarii, Lyngbya semiplena, Microcoleus acutirostris, Myxosarcina gloeocapsoides, Aiolocolax pulchella, Antithamnion densum, Antithamnion villosum, Antithamnionella spirographidis, Dasya sessilis, Furcellaria lumbricalis, Neosiphonia harveyi, Porphyrostromium boryanum, Chorda filum, Dictyopteris ambigua, Sphacelaria rigidula, Undaria pinnatifida, Vaucheria coronata, Vaucheria velutina, Ulothrix implexa, Ulva scandinavica, and Umbraulva olivascens) and 33 were recorded for the first time in the north of Portugal. Alien species have increased in number and extended their distribution range over the last 10 years in the study area. Distribution shifts of northern cold water species with southern distribution limit in the north of Portugal were not consistent among species.

Continuando con los estudios para la actualización del inventariado de la flora bentónica marina del Atlántico Ibérico.En este trabajo se incluye nueva información de distribución para 18 especies (3 Cyanobacteria, 9 Rhodophyta, 4 Ochrophyta, 2 Chlorophyta) de algas bentónicas marinas, recolectadas en el intermareal y submareal de 46 localidades del atlántico ibérico norte. Atendiendo a la distribución de las especies recolectadas, cabe destacar una nueva cita para Europa (Plocamium cf. ovicorne), 3 nuevas citas para Galicia (Calothrix consociata, Lyngbya martensiana y Centroceras gasparrinii), 14 nuevas citas provinciales y 8 segundas citas provinciales. Además dos especies (Spermothamnion strictum y Punctaria plantaginea) son excluidas de la flora de Galicia después, de estudiar el único material de herbario testigo de las citas.et al. 2005a-b, 2006, 2008, 2012, 2014, 2015, 2016), se presentan nuevas citas y correcciones florísticas que completan el actual inventario de la biodiversidad marina de Galicia (Bañón 2017). La mayoría de las muestras se conservaron en formalina al 4% y la conservación definitiva se realizó en pliegos de herbario, depositados en el herbario de la Universidad de Santiago de Compostela (SANT), así como en preparaciones semipermanentes en Karo®. También se estudiaron pliegos de herbario del Nationaal Herbarium Nederland, para la verificación o corrección de citas antiguas. Paralelamente, se conservaron fragmentos sin formolar de algunas especies en gel de sílice para estudios moleculares.

Sexual structures of Ptilothamnion sphaericum and Pterosiphonia complanata are described for the first time. Spermatangial heads of P. sphaericum are densely clustered in short lateral branchlets, each cell of which bears up to three spermatangial heads. They consist of a stalk cell and 3-4 axial cells bearing a cluster of spermatangial mother cells that cut-off 1-2 spermatangia. The last two cells in female axes of P. sphaericum are relatively short, with the hypogenous cell longer and more similar to vegetative cells. The subapical cell bears three periaxial cells: two sterile and the supporting cell, which bears a four-celled carpogonial branch and one sterile cell. The hypogenous cell bears 1-2 involucral filaments prior to fertilization. These features support the placement of P. sphaericum in the genus Ptilothamnion. Spermatangial branches of Pterosiphonia complanata are borne on unbranched modified trichoblasts. They consist of an elongate suprabasal cell that bears a fertile central axis from which four periaxial cells arise, bearing quadrangular spermatangial mother cells that bear the spermatangia. Spermatangial branches have 1 (-3) apical sterile cells. Procarps of P. complanata consist of a four-celled carpogonial branch and two sterile cells borne on the supporting cell. These features are similar to all Pterosiphonia species for which they have been described.

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Erythroglossum lusitanicum is a foliose, turf-forming member of the Delesseriaceae that colonizes sand-covered intertidal rocks on the Atlantic Iberian Peninsula. We examined (i) the phenology of this alga and (ii) the structure and temporal dynamics of its associated flora at two sites over one year. Species diversity was low in the assemblage, which was dominated by E. lusitanicum. Assemblage structure was essentially constant through the year. There were, however, significant differences in E. lusitanicum characteristics between the two sites. At one, E. lusitanicum was more abundant, thalli were longer and wider, and the proportion of plants with tetrasporangia was higher than at the second location. At the first site, the phenological traits tracked a temporal cycle. Thallus length and blade width were highest in April; after gradual deterioration of the apical portions of the plants, individual sizes reached minimum values in July. Subsequently, individual growth rate was low and plant length was nearly constant from September to February. Tetrasporangia were common throughout most of the year; only in July they were totally absent. Temperature and daylength were inversely related to reproduction. Sexual reproductive structures were not observed. The abundant growth of basal proliferations suggests that vegetative propagation very probably plays an important role in the maintenance of E. lusitanicum populations.