Crusticorallina gen. nov., a nongeniculate genus in the subfamily Corallinoideae (Corallinales, Rhodophyta)

Molecular phylogenetic analyses of 18S rDNA (SSU) gene sequences confirm the placement of Crusticorallina gen. nov. in Corallinoideae, the first non-geniculate genus in an otherwise geniculate subfamily. Crusticorallina is distinguished from all other coralline genera by the following suite of morpho-anatomical characters: 1) sunken, uniporate gametangial and bi/tetrasporangial conceptacles, 2) cells linked by cell fusions, not secondary pit connections, 3) an epithallus of 1 or 2 cell layers, 4) a hypothallus that occupies 50% or more of the total thallus thickness, 5) elongate meristematic cells, 6) trichocytes absent. Four species are recognized based on rbcL, psbA and COI-5P sequences, C. painei sp. nov., the generitype, C. adhaerens sp. nov., C. nootkana sp. nov. and C. muricata comb. nov., previously known as Pseudolithophyllum muricatum. Type material of Lithophyllum muricatum, basionym of C. muricata, in TRH comprises at least two taxa, and therefore we accept the previously designated lectotype specimen in UC that we sequenced to confirm its identity. Crusticorallina species are very difficult to distinguish using morpho-anatomical and/or habitat characters, although at specific sites, some species may be distinguished by a combination of morpho-anatomy, habitat and biogeography. The Northeast Pacific now boasts six coralline endemic genera, far more than any other region of the world. This article is protected by copyright. All rights reserved

New insights in the systematics of Peyssonnelia and the Peyssonneliaceae (Rhodophyta), with emphasis on taxa from the Gulf of Mexico and Panama

ABSTRACT: "Peyssonnelia Decaisne comprises a worldwide group of non-calcified or calcified, crust-forming red algae of great ecological significance, with some species involved in the establishment of rhodoliths. Of the eight genera currently recognized in the family, Peyssonnelia, is widely viewed to contain the largest number of species. The number of distinct species of Peyssonneliaceae present in the Gulf of Mexico has increased from 6 to 21. Comparative morphology, chloroplast-encoded rbcL and nuclear LSU rDNA sequence data suggest that species of Peyssonnelia do not occur in the Gulf of Mexico, and that previously reported Peyssonnelia species for the region actually belong to other genera of the Peyssonneliales." (a) University of Louisiana at Lafayette (b) Smithsonian Institution (c) University of North Carolinainfo:eu-repo/semantics/publishedVersio

New Insights into the Genus Lithophyllum (Lithophylloideae, Corallinaceae, Corallinales) from Deepwater Rhodolith Beds Offshore the NW Gulf of Mexico

Hard bank rhodolith beds at 45–80 m depth offshore Louisiana in the Northwestern Gulf of Mexico harbor a diverse community of non-geniculate coralline algae spanning multiple lineages including both rhodolith-forming (biogenic) taxa and others encrusting autogenic rhodoliths. Identifying these members of the Corallinales to the correct genus and species is an ongoing process because many available names need to be validated by comparison to historical type specimens. A phylogenetic analysis of concatenated plastid (psbA), nuclear (LSU rDNA), and mitochondrial (COI) DNA sequences of non-geniculate corallines belonging to the subfamily Lithophylloideae (Corallinaceae), including newly generated sequences from recently collected specimens dredged at Ewing and Sackett Banks following the April 2010 Deepwater Horizon oil spill, reveals at least two distinct species of Lithophyllum sensu lato for the region. Scanning Electron Microscopy confirmed the presence of vegetative characters congruent with those for both Lithophyllum and Titanoderma. Lithophyllum is a newly reported genus for the northern Gulf of Mexico. The generic boundaries within the Lithophylloideae are addressed in light of possible evolutionary progenetic heterochrony that may have occurred within this subfamil

Gracilaria parva sp. nov. (Gracilariales, Rhodophyta) a Diminutive Species from the Tropical Eastern Pacific

DNA sequencing of the plastid encoded rbcL gene supported by morpho-anatomical features reveals Gracilaria parva sp. nov. from Panama and Ecuador in the tropical eastern Pacific Ocean. In the rbcL phylogram, G. parva occurs in a clade sister to the western Atlantic species G. galatensis. Morphologically and anatomically, G. parva is distinguished from two similar, described tropical eastern Pacific species, G. brevis and G. veleroae by its small size, to 2.5 cm tall with branch widths mostly <2 mm occasionally to 4 mm, and by its two to three cell layered cortex. Gracilaria brevis and G. veleroae are taller, have wider branches, and a one cell layered cortex. DNA sequencing is needed to resolve the many diminutive species in the tropical eastern Pacific, particularly those occurring in turf communities. DNA sequencing of historical type specimens from the 19th and 20th centuries is also needed to correctly apply names in this region

Neogoniolithon (Corallinales, Rhodophyta) on the Atlantic coast of Mexico, including N. siankanensis sp. nov.

This is the first revision of Neogoniolithon species on the east coast of Mexico based on both DNA sequences (psbA) and morpho-anatomical characters. Nine species names are provisionally applied based on morpho-anatomical comparisons with type specimens or with species descriptions: N. accretum, N. acropetum, N. erosum, N. mamillare, N. propinquum, N. rhizophorae, N. solubile, N. spectabile and N. strictum. For none of these species was type or topotype material sequenced, but all have their type localities in the subtropical or tropical western Atlantic Ocean. Neogoniolithon siankanensis is described on the basis of a distinctive branched thallus, apical tetrasporangial conceptacles and DNA sequence. Another four species are present, each characterized by DNA sequence, but insufficient reproductive material was available to adequately describe these species. A suite of vegetative and reproductive characters can adequately segregate the currently named Mexican east coast Neogoniolithon species, including 1) branched versus unbranched thalli, 2) monomerous versus dimerous construction, 3) disposition of trichocytes, 4) interior dimensions of mature tetrasporangial conceptacles, 5) number of cell layers comprising tetrasporangial conceptacle roof and 6) shape of cells that line tetrasporangial pore canal. Morpho-anatomical descriptions and distributions are provided for all named species

Molecular and Morphological Diversity of Lithothamnion spp. (Hapalidiales, Rhodophyta) from Deepwater Rhodolith Beds in the Northwestern Gulf of Mexico

In the Northwestern Gulf of Mexico (NWGMx), subtidal rhodolith beds offshore Louisiana at 45–80 m depth harbor a diverse community of uncharacterized non-geniculate coralline algae including both biogenic and autogenic rhodoliths and other encrusting taxa. Identifying specimens to their correct genus and species is an ongoing process because many available names remain to be validated by comparison to type specimens. Here, comparative DNA sequencing ( psb A, UPA, and COI) and scanning electron microscopy (SEM) are used to assess the molecular and morphological diversity of the rhodolith-forming specimens belonging to the generic concept of Lithothamnion . Phylogenetic and species delimitation analyses of the newly generated sequences from recently dredged specimens at Ewing and Sackett Banks offshore Louisiana reveal the presence of at least six species of Lithothamnion , whose generic placement is confirmed by SEM images of features considered characteristic for the genus. More broadly, our analyses indicate at least eight Lithothamnion species are found in the Gulf of Mexico. Phylogenetic analyses of single ( psb A and COI) and concatenated markers ( psb A, COI and UPA) show that Lithothamnion is polyphyletic

Calcifying algae maintain settlement cues to larval abalone following algal exposure to extreme ocean acidification

Ocean acidification (OA) increasingly threatens marine systems, and is especially harmful to calcifying organisms. One important question is whether OA will alter species interactions. Crustose coralline algae (CCA) provide space and chemical cues for larval settlement. CCA have shown strongly negative responses to OA in previous studies, including disruption of settlement cues to corals. In California, CCA provide cues for seven species of harvested, threatened, and endangered abalone. We exposed four common CCA genera and a crustose calcifying red algae, Peyssonnelia (collectively CCRA) from California to three pCO levels ranging from 419-2,013 µatm for four months. We then evaluated abalone (Haliotis rufescens) settlement under ambient conditions among the CCRA and non-algal controls that had been previously exposed to the pCO treatments. Abalone settlement and metamorphosis increased from 11% in the absence of CCRA to 45-69% when CCRA were present, with minor variation among CCRA genera. Though all CCRA genera reduced growth during exposure to increased pCO , abalone settlement was unaffected by prior CCRA exposure to increased pCO . Thus, we find no impacts of OA exposure history on CCRA provision of settlement cues. Additionally, there appears to be functional redundancy in genera of CCRA providing cues to abalone, which may further buffer OA effects

New branched Porolithon species (Corallinales, Rhodophyta) from the Great Barrier Reef, Coral Sea, and Lord Howe Island

Porolithon is one of the most ecologically important genera of tropical and subtropical crustose (non-geniculate) coralline algae growing abundantly along the shallow margins of coral reefs and functioning to cement reef frameworks. Thalli of branched, fruticose Porolithon specimens from the Indo-Pacific Ocean traditionally have been called P. gardineri, while massive, columnar forms have been called P. craspedium. Sequence comparisons of the rbcL gene both from type specimens of P. gardineri and P. craspedium and from field-collected specimens demonstrate that neither species is present in east Australia and instead resolve into four unique genetic lineages. Porolithon howensis sp. nov. forms columnar protuberances and loosely attached margins and occurs predominantly at Lord Howe Island; P. lobulatum sp. nov. has fruticose to clavate forms and free margins that are lobed and occurs in the Coral Sea and on the Great Barrier Reef (GBR); P. parvulum sp. nov. has short (<2 cm), unbranched protuberances and attached margins and is restricted to the central and southern GBR; and P. pinnaculum sp. nov. has a mountain-like, columnar morphology and occurs on oceanic Coral Sea reefs. A rbcL gene sequence of the isotype of P. castellum demonstrates it is a different species from other columnar species. In addition to the diagnostic rbcL and psbA marker sequences, the four new species may be distinguished by a combination of features including thallus growth form, margin shape (attached or unattached), and medullary system (coaxial or plumose). Porolithon species, because of their ecological importance and sensitivity to ocean acidification, need urgent documentation of their taxonomic diversity

Molecular Assisted Identification Reveals Hidden Red Algae Diversity from the Burica Peninsula, Pacific Panama

The marine flora of Panama harbors a rich diversity of green, red and brown algae,and despite chronic understudy, it is reported as the second most diverse marine flora along thePacific Central American coast, with 174 macroalgal species. Extensive new collections and molecularassisted identification (MAI) by an international team of researchers has revealed an even greaterdiversity for this country. Here, the intertidal and shallow subtidal marine flora of the remoteBurica Peninsula is introduced. This area is characterized by an uplifted extensive intertidal flatcomposed of firm, sedimentary benthos known as mudrock, on which abundant algal communitiesthrive, even during extended periods of exposure. A collection of nearly 200 brown, green and redmacroalgae specimens representing the first marine floristic inventory of this region was made inJanuary 2011, and results of analyses of 45 foliose red algae specimens are presented. DNA sequencedata for several loci (rbcL-3P; COI-5P; UPA) have been generated for molecular assisted identificationand to guide morphological assessments. Twenty-six species were identified among the specimensincluding 21 new Pacific Panama records, as well as previously unrealized transisthmian distributions,and two new species, Neorubra parvolacertoides sp. nov. and Grateloupia irregularis sp. novNational Science Foundation/[0743334]/NSF/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Mesophyllum erubescens (Corallinales, Rhodophyta)—so many species in one epithet

The name Mesophyllum erubescens has been applied to protuberant rhodolith specimens which sometimes occur abundantly, as well as to encrusting specimens in tropical and temperate waters in the Western Pacific, Indian and Western Atlantic Oceans. A DNA sequence, representing about 20% of the rbcL gene, was obtained from the 140 year old holotype specimen collected in the Fernando de Noronha Archipelago by the Challenger Expedition. This sequence was identical to field-collected topotype specimens as well as to specimens ranging south along the coast of Brazil. Sequences for psbA from these same Brazilian specimens and specimens from the east coast of Mexico were identical or differed by 1 base pair. In contrast, specimens called M. erubescens based on morpho-anatomical characters in the Pacific Ocean differed from Western Atlantic Ocean specimens by 2.5–13.1%, indicating that these represent numerous distinct species. All reports of non-geniculate coralline species said to be widely distributed across different oceans or in different biogeographic provinces based on morpho-anatomical characters need to be verified by DNA sequence