LAURENCIA MARILZAE SP. NOV. (CERAMIALES, RHODOPHYTA) FROM THE CANARY ISLANDS, SPAIN, BASED ON MORPHOLOGICAL AND MOLECULAR EVIDENCE¹

Abstract

Laurencia marilzae Gil-Rodríguez, Sentíes et M.T. Fujii sp. nov. is described based on specimens that have been collected from the Canary Islands. This new species is characterized by distinctive yelloworange as its natural habitat color, a terete thallus, four pericentral cells per vegetative axial segment, presence of secondary pit-connections between adjacent cortical cells, markedly projecting cortical cells, and also by the presence of corps en cerise (one per cell) present in all cells of the thallus (cortical, medullary, including pericentral and axial cells, and trichoblasts). It also has a procarp-bearing segment with five pericentral cells and tetrasporangia that are produced from the third and fourth pericentral cells, which are arranged in a parallel manner in relation to fertile branchlets. The phylogenetic position of this taxon was inferred based on chloroplast-encoded rbcL gene sequence analyses. Within the Laurencia assemblage, L. marilzae formed a distinctive lineage sister to all other Laurencia species analyzed. Previously, a large number of unique diterpenes dactylomelane derivatives were isolated and identified from this taxon. L. marilzae is morphologically, genetically, and chemically distinct from all other related species of the Laurencia complex described.

Overview of the taxonomy and of the major secondary metabolites and their biological activities related to human health of the Laurencia complex (Ceramiales, Rhodophyta) from Brazil

“…Many species have no defined taxonomic boundaries and present extensive morphological plasticity, making their taxonomic delimitation difficult. In this context, the use of molecular markers has proven to be useful for delimiting the taxa and inferring their phylogenetic relationships and has corroborated the current classification system (Nam et al, 2000;McIvor et al, 2002;Abe et al, 2006;Fujii et al, 2006;Díaz-Larrea et al, 2007;Cassano et al, 2009;Gil-Rodríguez et al, 2009;Martin-Lescanne et al, 2010;Rocha-Jorge et al, 2010).…”

Transcriptomic analysis of the red seaweed Laurencia dendroidea (Florideophyceae, Rhodophyta) and its microbiome

“…Despite the large number of studies based on the chemical composition of Laurencia species, the genetic knowledge regarding this genus is currently restricted to taxonomic markers [39,40]. The genome size of L. dendroidea is estimated to be about 833 Mbp, based on a study of another species of the same genus [41], but gene sequences from this species have not previously been described.…”

Comparative analysis of the corps en cerise in several species of Laurencia (Ceramiales, Rhodophyta) from the Atlantic Ocean

“…The photographs were taken with a digital camera coupled to a Zeiss microscope (Göettingen, Germany) and/or by photomicrography on a Zeiss Axioskop 2 microscope (Göettingen, Germany). & Fujii, 1985;Gil-Rodríguez & Haroun, 1992;Cassano et al, 2006Cassano et al, , 2008aGil-Rodríguez et al, 2009;Rocha-Jorge et al, 2010;Sentíes et al, 2010Sentíes et al, , 2011 (Machín-Sánchez et al, 2012) and the latter to L. dendroidea .…”