Phymatolithopsis gen. nov. (Hapalidiales, Corallinophycidae, Rhodophyta) based on molecular and morpho‐anatomical evidence

Abstract

A multigene (psbA, rbcL, 18S rDNA) molecular phylogeny of the genus Phymatolithon showed a polyphyletic grouping of two monophyletic clades within the Hapalidiales. DNA sequence data integrated with morpho-anatomical comparisons of type material and of recently collected specimens were used to establish Phymatolithopsis gen. nov. with three species, P. prolixa comb. nov., the generitype, P. repanda comb. nov. and P. donghaensis sp. nov. Phymatolithopsis is sister to Mesophyllum and occurs in a clade distinct from Phymatolithon and boreal species currently assigned to Lithothamnion. Morphoanatomically, Phymatolithopsis is comprised of species that are non-geniculate and encrusting, bear epithallial cells with rounded walls (not flared), subepithallial initials that are usually as short as or shorter than their immediate inward derivatives, conceptacle primordia from all stages forming superficially directly from subepithallial initials, mature carposporangial conceptacles with a discontinuous fusion cell, gonimoblast filaments that develop at the margins of the fusion cell around the periphery of the carposporangial conceptacle chambers, and multiporate tetra/bisporangial conceptacles. Phymatolithopsis can be distinguished from Phymatolithon by the origin of its conceptacle primordia, which are initiated superficially, directly from the layer of subepithallial initials below the epithallial cells and the distribution of gonimoblast filaments in carposporangial conceptacles, that are at the margins of the fusion cells.

Settlement cue selectivity by larvae of the destructive crown-of-thorns starfish

“…Experimental treatments included 14 living coralline algae species and one living Peyssonneliaceae alga (collectively referred to as coralline algae in this study; table 1 ) with relatively high abundance on Australia's Great Barrier Reef (GBR), and structural control (sterile aragonite) and filtered seawater (FSW) control treatments. A diversity of coralline algae were collected from two central GBR locations (electronic supplementary material, §S2), identified based on morpho-anatomical features (electronic supplementary material, §S2) and molecular sequencing (electronic supplementary material, §S3, §S4, following [ 40 ]), and cut into replicate 5 × 5 mm live chips for use in experiments.…”

Salmon farming alters the structure and functioning of Norwegian maerl bed communities

“…Gabrielson, Maneveldt, Hughey & V. Peña and Boreolithothamnion glaciale (Kjellman) P.W. Gabrielson, Maneveldt, Hughey & V. Peña, respectively (Gabrielson et al, 2023). Representative specimens from both maerl species are preserved in Trondheim Herbarium (TRH).…”

A new species of Phymatolithon Foslie, P. abuqirensis (Hapalidiaceae, Hapalidiales), from Mediterranean Egypt

“…Molecular work also showed a complex relationship with northern species of Hapalidiaceae using a three-gene analysis (SSU, psbA, rbcL) (Adey et al, 2015). Most recently, a new genus, Phymatolithopsis, has been described by Jeong et al (2022) for some species previously assigned to Phymatolithon. This new genus is sister to Mesophyllum and located in a clade distinct from Phymatolithon.…”

“…This new genus is sister to Mesophyllum and located in a clade distinct from Phymatolithon. Phymatolithopsis is differentiated from Phymatolithon by morphological features such as the origin of the conceptacle primordia and the distribution of gonimoblast filaments (Jeong et al, 2022). The description of this new genus included the taxonomic transfer of Phymatolithon prolixum and P. repandum to Phymatolithopsis prolixa and P. repanda, respectively (Jeong et al, 2022).…”