Search

Nongeniculate coralline algae are difficult to identify based solely on morpho‐anatomy. To address the systematics of several taxonomically challenging taxa, we analyzed DNA sequences of a short portion (118–296 base pairs) of the 3′ end of the rbcL gene from three type specimens. The analyses revealed that Harveylithon munitum (basionym: Lithophyllum munitum), described in 1906 from Cave Cays, Exuma Chain, Bahamas, is conspecific with both Goniolithon accretum and Goniolithon affine, described in 1906 from Sand Key, Florida and in 1907 from Culebra Island, Puerto Rico, respectively. Lithophyllum munitum and G. accretum were described in the same 1906 publication and have equal priority. We have selected the currently accepted and most commonly used name H. munitum to apply to this entity. Comparative analyses of rbcL, psbA, UPA, COI, and LSU sequences from contemporary field‐collected specimens revealed that H. munitum currently inhabits mesophotic rhodolith beds in the northwestern Gulf of Mexico, as well as the intertidal zone in the Florida Keys, Honduras, Atlantic Mexico, Caribbean Panama, and Guadeloupe, French West Indies. Species delimitation analyses reveal that the Western Atlantic and Australian H. munitum populations may be separate species. Two new species of Harveylithon from the northwestern Gulf of Mexico and one new species from the southwestern Gulf of Mexico, the Caribbean, and the Red Sea were also identified in the analyses and are described. [ABSTRACT FROM AUTHOR]

The gelatinous, calciferous red alga Renouxia antillana was described in 1995 based on material from Guadeloupe, French West Indies, and accommodated in a new family and order (Rhodogorgonaceae, Rhodogorgonales) along with the genus Rhodogorgon from Belize and Caribbean Panama. For more than 20 years, Renouxia has remained monotypic, with rare reports in the Caribbean and the Indo-Pacific (from Réunion Island to French Polynesia). DNA-based analyses of recently collected Renouxia specimens from Egypt showed that they are not conspecific with the Caribbean R. antillana and are described as R. marerubra sp. nov. Uncorrected p-distances between the Red Sea specimens and the generitype were 8.0% for COI, 6.5-7.3% for rbcL and 3.1% for UPA. Morphological and anatomical features are also presented for the newly described species and compared to its congener, with the first documented report of monoecism in the Rhodogorgonales. Besides the new record of Renouxia from the Red Sea, the geographic distribution of the genus is here extended with additional records from Sri Lanka, Indonesia, as well as the islands of Guam and Kosrae in the Western Pacific. The UPA phylogeny suggests that these new distribution records may also represent undescribed species, with representatives in two distinct genetic groups. [ABSTRACT FROM AUTHOR]

Background A second species in the siphonous green algal genus Avrainvillea was recently discovered off the island of O'ahu in the Main Hawaiian Islands. Specimens were collected from Honolulu Harbor, including its entrance channel, and near Ke'ehi Harbor. These locations are both in Mālama Bay on O'ahu's south shore in or adjacent to urbanized estuaries, respectively. In situ observations, morphological and molecular assessments were conducted to examine the alga's habit and distribution, as well as to assess its putative species identification. New information The alga occurred in sand as single individuals or in clusters of several individuals at both sites, and near or within seagrass beds (Halophila decipiens) and algal meadows composed of the green alga Halimeda kanaloana and an unidentified Udotea species at the Ke'ehi Harbor site. All analyses supported both populations as representative of the same taxa, reported until further investigation in the broad Pacific as Avrainvillea cf. erecta based on morphological and molecular analyses. This record of a second Avrainvillea species in Hawai'i is of particular concern considering that an alga recognized as A. amadelpha, first observed in 1981 from two locales on O'ahu's south shore, has become invasive in Hawai'i's intertidal to mesophotic environments. [ABSTRACT FROM AUTHOR]

The tropical alga previously recognized as Gibsmithia hawaiiensis (Dumontiaceae, Rhodophyta) was recently suggested to represent a complex of species distributed throughout the Indo-Pacific Ocean and characterized by a peculiar combination of hairy (pilose) gelatinous lobes growing on cartilaginous stalks. Phylogenetic reconstructions based on three genetic markers are presented here with the inclusion of new samples. Further diversity is reported within the complex, with nine lineages spread in four major phylogenetic groups. The threshold between intra- and interspecific relationships was assessed by species delimitation methods, which indicate the existence of 8-10 putative species in the complex. Two species belonging to the G. hawaiiensis complex are described here: Gibsmithia malayensis sp. nov. from the Coral Triangle and Gibsmithia indopacifica sp. nov., widely distributed in the Central and Eastern Indo-Pacific. Morphological differences in the vegetative and reproductive structures of the newly described species are provided and compared to the previously described species of the complex. Additional lineages represent putative species, which await further investigation to clarify their taxonomic status. Gibsmithia hawaiiensis sensu stricto is confirmed to be endemic to the Hawaiian Islands, and Gibsmithia eilatensis is apparently confined to the Red Sea, with an expanded distribution in the region. New records of the G. hawaiiensis complex are reported from Egypt, Saudi Arabia, Indonesia, Philippines, and the Federated States of Micronesia, indicating that the complex is more broadly distributed than previously considered. The isolated position of Gibsmithia within the Dumontiaceae is corroborated by molecular data. [ABSTRACT FROM AUTHOR]

Interspecific systematics in the red algal order Sporolithales remains problematic. To re-evaluate its species, DNA analyses were performed on historical type material and recently collected specimens assigned to the two genera Sporolithon and Heydrichia. Partial rbcL sequences from the lectotype specimens of Sporolithon ptychoides (the generitype species) and Sporolithon molle, both from El Tor, Egypt, are exact matches to field-collected topotype specimens. Sporolithon crassum and Sporolithon erythraeum also have the same type locality; material of the former appears to no longer exist, and we were unable to PCR amplify DNA from the latter. A new species, Sporolithon eltorensis, is described from the same type locality. We have not found any morpho-anatomical characters that distinguish these three species. No sequenced specimens reported as S. ptychoides from other parts of the world represent this species, and likely reports of S. ptychoides and S. molle based on morpho-anatomy are incorrect. A partial rbcL sequence from the holotype of Sporolithon dimotum indicates it is not a synonym of S. ptychoides, and data from the holotype of S. episporum confirm its specific recognition. DNA sequences from topotype material of Heydrichia woelkerlingii, the generitype species, and isotype material of Heydrichia cerasina confirm that these are distinct species; the taxon reported to be H. woelkerlingii from New Zealand is likely an undescribed species. Type specimens of all other Sporolithon and Heydrichia species need to be sequenced to confirm that they are distinct species; morpho-anatomical studies have proved inadequate for this task. [ABSTRACT FROM AUTHOR]

The siphonous green algal family Caulerpaceae includes the monotypic genus Caulerpella and the species-rich genus Caulerpa. A molecular phylogeny was inferred from chloroplast tufA and rbcL DNA sequences analyzed together with a five marker dataset of non-caulerpacean siphonous green algae. Six Caulerpaceae lineages were revealed, but relationships between them remained largely unresolved. A Caulerpella clade representing multiple cryptic species was nested within the genus Caulerpa. Therefore, that genus is subsumed and Caulerpa ambigua Okamura is reinstated. Caulerpa subgenus status is proposed for the six lineages substantiated by morphological characters, viz., three monotypic subgenera Cliftonii, Hedleyi, and Caulerpella, subgenus Araucarioideae exhibiting stolons covered with scale-like appendages, subgenus Charoideae characterized by a verticillate branching mode, and subgenus Caulerpa for a clade regarded as the Caulerpa core clade. The latter subgenus is subdivided in two sections, i.e., Sedoideae for species with pyrenoids and a species-rich section Caulerpa. A single section with the same name is proposed for each of the other five subgenera. In addition, species status is proposed for Caulerpa filicoides var. andamanensis (W.R. Taylor). All Caulerpa species without sequence data were examined (or data were taken from species descriptions) and classified in the new classification scheme. A temporal framework of Caulerpa diversification is provided by calibrating the phylogeny in geological time. The chronogram suggests that Caulerpa diversified into subgenera and sections after the Triassic- Jurassic mass extinction and that infra-section species radiation happened after the Cretaceous- Tertiary mass extinction. [ABSTRACT FROM AUTHOR]