New records of benthic marine algae from the Canary Islands (eastern Atlantic Ocean): morphology, taxonomy and distribution

Abstract

Four species of marine algae are reported from the Canary Islands for the first time. Our report of the western Atlantic Gelidiella setacea (Gelidiales, Rhodophyta) is the first from the eastern Atlantic Ocean. Pseudotetraspora marina (Tetrasporales, Chlorophyta) previously known on the eastern side of the Atlantic Ocean from temperate saltmarshes only, is now reported growing in the shallow sublittoral zone, the habitat in which tropical western Atlantic populations also occur. The presence of Lomentaria chylocladiella (Rhodymeniales, Rhodophyta) represents the first report in the Atlantic Ocean of a species previously thought to be endemic to the Mediterranean Sea. The record of the widely distributed Acrochaetium hallandicum (Acrochaetiales, Rhodophyta) was not unexpected. Specimens of A. hallandicum have vegetative cells with a single lobate parietal chloroplast with a single pyrenoid, a feature that among acrochaetioid algae occurs exclusively in the genus Colaconema (Colaconematales), and consequently the species is transferred to this genus. Fertile sporophytes are described for Gelidiella setacea, a species previously known only in its vegetative condition. Cruciately to irregularly divided sporangia are regularly arranged in transverse rows in stichidia laterally formed on the axes. The species is transferred to the genus Parviphycus on the basis of the morphology of the stichidia and the distichous pattern of apical division exhibited by the axes, both exclusive features of this genus.

Diversity and patterns of marine non‐native species in the archipelagos of Macaronesia

“…The biogeographical position of the Canary Islands has been recognized as the major element for the richness of its marine biota (Haroun & Herrera, 2001), with a high interest in phycology, where several publications were produced over the years (e.g. Afonso‐Carrillo et al, 2007; Gil‐Rodríguez & Afonso‐Carrillo, 1980; Haroun & Herrera, 2001; Sangil et al, 2012). Therefore, it is no surprise that macroalgae are amongst the most detected NNS taxa in this archipelago.…”

New records of seaweeds and filamentous cyanobacteria from Trindade Island: an updated checklist to support conservation guidelines and monitoring of environmental changes in the southern Atlantic archipelagos

“…Exsiccate vouchers of the new records were deposited in the Herbarium of the Botanical Museum of Curitiba. Morphological taxonomic identification was performed, using as comparative material specialized and illustrated descriptions of the species from the Brazilian oceanic islands (Villaça et al 2006, Burgos 2011, Burgos et al 2009, Pereira-Filho et al 2011, 2015; southeastern (Cordeiro-Marino 1978, Crispino 2007, Coto 2007 (Barnes et al 2015); and the Canary Islands (Sanson et al 2002, Haroun et al 2002, Afonso-Carrillo et al 2007).…”

“…This opportunistic group deserves attention as a bioindicator of changes. Similarly, Afonso-Carrillo et al (2007) reported that a subtidal algae bed in the Canary Islands has undergone changes, indicated by the proliferation of the ephemeral green algae Pseudotetraspora marina, a recent and probably introduced species reported for the eastern Atlantic Ocean. Sangil et al (2012) associated the shifts in the distribution and biomass of ephemeral species with the 2°C warming in the SST resulting from the weakening of the cold Canary current.…”

“…Several studies have reported changes in macroalgae diversity, mainly in coastal ecosystems (Iles et al 2012, Duarte et al 2013, Sjøtun et al 2015. Insular areas have also been addressed, including studies in Tristan da Cunha (Saunders et al 2019), Ascension (Barnes et al 2015, Tsiamis et al 2014, the Canary Islands (Afonso-Carrillo et al 2007, Sanson et al 2002, Haroun et al 2002 and the Azores islands, located in the southern and northern zones of the Mid-Atlantic Ridge (MAR), respectively, and Trindade between Brazil and MAR. Large-scale and mainly climate-driven distributional and biogeographical changes to temperate and polar ecosystems have been broadly reported (Sjøtun et al 2015, Pellizzari et al 2017, Oliveira et al 2020).…”

Diversidade de Gelidiales (Rhodophyta) baseada em marcadores moleculares e estudos morfoanatômicos para região Sudeste do Brasil

“…Esta espécie possui até 3,0 cm de altura e o diâmetro do ramo ereto pode alcançar 150-200 µm (Taylor, 1960), podendo apresentar ramificações. A medula do ramo ereto é constituída de cinco camadas, sendo uma fileira central contendo a célula axial e 2-4 células periaxiais e mais duas camadas de células medulares opostas (Afonso-Carrillo et al, 2007). Mesmo sem a presença de estruturas férteis no espécime deste estudo, as estruturas vegetativas indicam não se tratar de Pa. setaceous, já que o espécime é menor, em altura e diâmetro, não possui ramificações e a medula do ramo ereto é constituída apenas pela fileira central composta pela célula axial e células periaxiais.…”