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We described the complete mitochondrial genome of Gracilaria chilensis (Gracilariales), an economically important agarophyte alga. The genome was a 26,898 bp circular DNA with 27.6% guanine-cytosine (GC) content, and it encoded 25 protein-coding genes, two ribosomal RNAs (rRNAs), 26 transfer RNAs (tRNAs), and an intron (499 bp) in trnI. The gene composition was similar to that of the published mitogenome of G. salicornia; however, one inverted and several direct repeat sequences occurred between secY and orf148 genes, resulting in duplicated trnR and trnS tRNA sequences. The mitochondrial genome also contained three integrated partial plasmid sequences, which were reported for G. robusta (Gro4059). [ABSTRACT FROM AUTHOR]

The red algal family Kallymeniaceae was surveyed along the west coast of Canada using the DNA barcode (COI-5P- 5' region of the mitochondrial cytochrome c oxidase I gene) as a species identification tool. A total of 253 specimens field identified as Pugetia spp. subsequently resolved as five genetic species groups, although only two are reported in the flora. Additionally, COI-5P data were available for the Chilean P. chilensis, which resolved as a distinct species. Subsequent analysis of the internal transcribed spacer of the ribosomal cistron and the universal plastid amplicon (domain V of the 23S rRNA gene) resolved the same groups as COI-5P. Phylogenetic relationships of the Canadian groups were investigated using large-subunit ribosomal DNA (LSU) and a combined analysis of LSU and COI-5P data. One species was divergent from the Pugetia spp. in all analyses and grouped closely with the kallymeniacean genera Erythrop/iylluin (Kallymeniaceae, Gigartinales) and Kallymeniopsis (Kallymeniaceae, Gigartinales) - it is here described as Beringia wynnei sp. nov. The other 'Pugetia' species fell into two divergent clusters in phylogenetic analyses, differing also in blade thickness, carpogonial branch morphology and the association of the auxiliary cell relative to the carpogonium (procarpic vs nonprocarpic). We retain the genus Pugetia for the type species P. fragilissima and P. cryplica sp. nov. and describe the new genus Salishia for Salishiajirnia (Kylin) comb. nov., S. sanguinea (Montagne) comb. nov. and S. chilensis (J. Agardh) comb. nov. Finally, we completed morphological and anatomical examinations of other Pugetia species to provide a comprehensive review of the genus. [ABSTRACT FROM AUTHOR]

A filamentous 'acrochaetioid' red algal epiphyte on Posidonia from Madagascar was isolated into culture. It reproduces solely by monosporangia and the spherical spores have gliding motility that differs from amoeboid spore motility seen with time-lapse video microscopy in most Acrochaetiales and Colaconematales. Electron microscopy reveals that a peripheral encircling thylakoid is absent in the chloroplast, Golgi bodies are associated with mitochondria, and pit plugs have platelike outer and inner caps and lack a cap membrane. Low-molecular-weight carbohydrates are floridoside and trehalose. Molecular evidence (small subunit, large subunit and EF2 sequences) resolved this taxon as a completely novel lineage of the Nemaliophycidae, and it is here described as Rhodachlya madagascarensis J.A. West et al., gen. et sp. nov. In light of the unusual combination of ultrastructural features and the lack of affinity to any of the currently recognized families and orders in molecular analyses, this alga forms the basis of a new family, Rhodachlyaceae G.W. Saunders et al., fam. nov., and order, Rhodachlyales G.W. Saunders et al., ord. nov., of the subclass Nemaliophycidae. [ABSTRACT FROM AUTHOR]

We present a contemporary monograph of the poorly known red algal genus Leptofauchea and provide a list of diagnostic features to distinguish it from other rhodymenialean genera. Of six species included in this genus at the time of initiating this study, we accept only the type species Leptofauchea nitophylloides (J. Agardh) Kylin, L. rhodymenioides W.R. Taylor, and L. pacifica E.Y. Dawson. To these we add a new species of Leptofauchea, L. chiloensis sp. nov., which we collected on repeated trips to the Golfo de Ancud, Isla Grande de Chiloé, Chile. An additional species from Western Australia (‘L. anastomosans’ sensu Huisman) is acknowledged, but we had insufficient material to describe adequately this entity. Leptofauchea brasiliensis Joly is shown to be a likely species of the Phyllophoraceae, Gigartinales, while the recently described L. earleae Gavio & Fredericq lacks diagnostic features of the genus—both species are here excluded from the genus. Material was not available for L. auricularis E.Y. Dawson, and we thus cannot confirm its taxonomic position. We have also studied South African specimens traditionally assigned to ‘L. anastomosans’ sensu R.E. Norris & Aken (a specific epithet correctly assigned to Australian and Indonesian specimens referable to the genus Asteromenia) and conclude that they are not representative of Leptofauchea. Molecular analyses indicate that the genus Leptofauchea, as recognized here, represents a distinct lineage within the rhodymenialean family Faucheaceae, where it is sister to the genus Webervanbossea. [ABSTRACT FROM AUTHOR]