Kimberly Y. Conklin

A molecular method for identification of the morphologically plastic invasive algal genera Eucheuma and Kappaphycus (Rhodophyta, Gigartinales) in Hawaii

A paucity of diagnostic morphological characters for identification and high morphological plasticity within the genera Eucheuma and Kappaphycus has led to confusion about the distributions and spread of three introduced eucheumoid species in Hawaii. Entities previously identified as E. denticulatum, K. alvarezii, and K. striatum have had profound negative effects on Oahu’s coral reef ecosystems. The use of molecular tools to aid identification of algal species has been promising in other morphologically challenging taxa. We used three molecular markers (partial nuclear 28S rRNA, partial plastid 23S rRNA, and mitochondrial 5′ COI) and followed a DNA barcoding-like approach to identify Eucheuma and Kappaphycus samples from Hawaii. Neighbor-joining analyses were congruent in their separation of Eucheuma and Kappaphycus, and the resulting clusters were consistent with those revealed for global comparisons with the mitochondrial cox2-3 spacer and GenBank data. Based on these results, new insights were revealed into the distribution of these groups in Hawaii.

The Hawaiian Rhodophyta Biodiversity Survey (2006-2010): a summary of principal findings

BackgroundThe Hawaiian red algal flora is diverse, isolated, and well studied from a morphological and anatomical perspective, making it an excellent candidate for assessment using a combination of traditional taxonomic and molecular approaches. Acquiring and making these biodiversity data freely available in a timely manner ensures that other researchers can incorporate these baseline findings into phylogeographic studies of Hawaiian red algae or red algae found in other locations.ResultsA total of 1,946 accessions are represented in the collections from 305 different geographical locations in the Hawaiian archipelago. These accessions represent 24 orders, 49 families, 152 genera and 252 species/subspecific taxa of red algae. One order of red algae (the Rhodachlyales) was recognized in Hawaii for the first time and 196 new island distributional records were determined from the survey collections. One family and four genera are reported for the first time from Hawaii, and multiple species descriptions are in progress for newly discovered taxa. A total of 2,418 sequences were generated for Hawaiian red algae in the course of this study - 915 for the nuclear LSU marker, 864 for the plastidial UPA marker, and 639 for the mitochondrial COI marker. These baseline molecular data are presented as neighbor-joining trees to illustrate degrees of divergence within and among taxa. The LSU marker was typically most conserved, followed by UPA and COI. Phylogenetic analysis of a set of concatenated LSU, UPA and COI sequences recovered a tree that broadly resembled the current understanding of florideophyte red algal relationships, but bootstrap support was largely absent above the ordinal level. Phylogeographic trends are reported here for some common taxa within the Hawaiian Islands and include examples of those with, as well as without, intraspecific variation.ConclusionsThe UPA and COI markers were determined to be the most useful of the three and are recommended for inclusion in future algal biodiversity surveys. Molecular data for the survey provide the most extensive assessment of Hawaiian red algal diversity and, in combination with the morphological/anatomical and distributional data collected as part of the project, provide a solid baseline data set for future studies of the flora. The data are freely available via the Hawaiian Algal Database (HADB), which was designed and constructed to accommodate the results of the project. We present the first DNA sequence reference collection for a tropical Pacific seaweed flora, whose value extends beyond Hawaii since many Hawaiian taxa are shared with other tropical areas.

What's in the air? Preliminary analyses of Hawaiian airborne algae and land plant spores reveal a diverse and abundant flora

Abstract: The airborne algae of Oahu, Hawaii was studied along a transect crossing from the leeward to the windward side of the Koolau Mountain Range in summer 2013. Algae were collected on agarized medium in petri dishes from a car window as the vehicle drove from Honolulu to Kailua, Oahu, through an elevation gradient of > 360 m and a rainfall gradient of c. 900–3150 mm yr−1. Light microscopy and molecular methods [18S ribosomal (r)RNA gene, 16S rRNA gene, and UPA sequences] were used to characterize a total of 97 operational taxonomic units from the transect. The airborne algal flora of the transect was dominated by cyanobacteria, followed by chlorophycean green algae, diatoms, and ferns and liverworts. This study is the first in Hawaii to incorporate molecular techniques into the identification of airborne algae.

Molecular diversity of Amansieae (Ceramiales, Rhodophyta) from the Hawaiian Islands: a multi‐marker assessment reveals high diversity within Amansia glomerata

Sixty‐one Hawaiian algal specimens corresponding to members of the tribe Amansieae (Amansia and Osmundaria) were compared through DNA sequence analysis. Short DNA barcode‐like sequences of mitochondrial cytochrome c oxidase subunit I (COI) and universal plastid amplicon (UPA) markers were obtained for as many of the specimens as possible, and a subset of specimens was also used for amplification and sequencing of the nuclear small‐subunit rRNA (SSU) gene for phylogenetic inference in a broader taxonomic context. Statistical parsimony analysis of the COI and UPA markers for A. glomerata produced relationships among the samples that were largely congruent with each other, although the UPA marker was more conserved. The COI marker yielded three lineages, and nucleotide divergences for these three lineages were intermediate to those typically reported for intraspecific and interspecific comparisons, suggesting that they represent either incipient species or a complex of closely related species. The COI and UPA sequences demonstrated little to no divergence for Osmundaria obtusiloba and the taxon referred to as Amansia fimbrifolia. In contrast, specimens identified as A. daemelii were identical in sequence to lineage 3 sequences of A. glomerata, and it is recommended that this taxon no longer be included in species lists for the Hawaiian flora. Phylogenetic reconstruction based on the SSU gene was largely unresolved, indicating that this marker may be of limited utility for this purpose in this group of algae, but a small amount of nucleotide variation was found for samples of A. glomerata.

The Hawaiian Algal Database: a laboratory LIMS and online resource for biodiversity data

BackgroundOrganization and presentation of biodiversity data is greatly facilitated by databases that are specially designed to allow easy data entry and organized data display. Such databases also have the capacity to serve as Laboratory Information Management Systems (LIMS). The Hawaiian Algal Database was designed to showcase specimens collected from the Hawaiian Archipelago, enabling users around the world to compare their specimens with our photographs and DNA sequence data, and to provide lab personnel with an organizational tool for storing various biodiversity data types.DescriptionWe describe the Hawaiian Algal Database, a comprehensive and searchable database containing photographs and micrographs, geo-referenced collecting information, taxonomic checklists and standardized DNA sequence data. All data for individual samples are linked through unique accession numbers. Users can search online for sample information by accession number, numerous levels of taxonomy, or collection site. At the present time the database contains data representing over 2,000 samples of marine, freshwater and terrestrial algae from the Hawaiian Archipelago. These samples are primarily red algae, although other taxa are being added.ConclusionThe Hawaiian Algal Database is a digital repository for Hawaiian algal samples and acts as a LIMS for the laboratory. Users can make use of the online search tool to view and download specimen photographs and micrographs, DNA sequences and relevant habitat data, including georeferenced collecting locations. It is publicly available at http://algae.manoa.hawaii.edu.

New Ulvaceae (Ulvophyceae, Chlorophyta) from mesophotic ecosystems across the Hawaiian Archipelago

Ulvalean algae (Chlorophyta) are most commonly described from intertidal and shallow subtidal marine environments worldwide, but are less well known from mesophotic environments. Their morphological simplicity and phenotypic plasticity make accurate species determinations difficult, even at the generic level. Here, we describe the mesophotic Ulvales species composition from 13 locations across 2,300 km of the Hawaiian Archipelago. Twenty‐eight representative Ulvales specimens from 64 to 125 m depths were collected using technical diving, submersibles, and remotely operated vehicles. Morphological and molecular characters suggest that mesophotic Ulvales in Hawaiian waters form unique communities comprising four species within the genera Ulva and Umbraulva, each with discrete geographic and/or depth‐related distributional patterns. Three genetically distinct taxa are supported by both plastid (rbcL and tufA) and nuclear (ITS1) markers, and are presented here as new species: Umbraulva kaloakulau, Ulva ohiohilulu, and Ulva iliohaha. We also propose a new Umbraulva species (Umbraulva kuaweuweu), which is closely related to subtidal records from New Zealand and Australia, but not formally described. To our knowledge, these are the first marine species descriptions from Hawai‘i resulting from the collaboration of traditional Hawaiian nomenclature specialists, cultural practitioners and scientists. The difficulty of finding reliable diagnostic morphological characters for these species reflects a common problem worldwide of achieving accurate identification of ulvalean taxa using solely morphological criteria. Mesophotic Ulvales appear to be distinct from shallow‐water populations in Hawai‘i, but their degree of similarity to mesophotic floras in other locations in the Pacific remains unknown.

A metabarcoding comparison of windward and leeward airborne algal diversity across the Ko‘olau mountain range on the island of O'ahu, Hawai‘i1

Airborne algae from sites on the windward (n = 3) and leeward (n = 3) sides of the Ko‘olau Mountain range of O‘ahu, Hawai‘i, were sampled for a 16 d period during January and February 2015 using passive collection devices and were characterized using Illumina MiSeq sequencing of the universal plastid amplicon marker. Amplicons were assigned to 3,023 operational taxonomic units (OTUs), which included 1,189 cyanobacteria, 1,009 heterotrophic bacteria, and 304 Eukaryota (of which 284 were algae and land plants). Analyses demonstrated substantially more OTUs at windward than leeward O‘ahu sites during the sampling period. Removal of nonalgal OTUs revealed a greater number of algal reads recovered from windward (839,853) than leeward sites (355,387), with the majority of these being cyanobacteria. The 1,234 total algal OTUs included cyanobacteria, diatoms, cryptophytes, brown algae, chlorophyte green algae, and charophyte green algae. A total of 208 algal OTUs were identified from leeward side samplers (including OTUs in common among samplers) and 1,995 algal OTUs were identified from windward samplers. Barcoding analyses of the most abundant algal OTUs indicated that very few were shared between the windward and leeward sides of the Ko‘olau Mountains, highlighting the localized scale at which these airborne algae communities differ. Back trajectories of air masses arriving on O‘ahu during the sampling period were calculated using the NOAA HY‐SPLIT model and suggested that the sampling period was composed of three large‐scale meteorological events, indicating a diversity of potential sources of airborne algae outside of the Hawaiian Islands.

Molecular and morphological variation of the red alga Spyridia filamentosa (Ceramiales, Rhodophyta) in the Hawaiian Archipelago

Conklin K.Y. and Sherwood A.R. 2012. Molecular and morphological variation of the red alga Spyridia filamentosa (Ceramiales, Rhodophyta) in the Hawaiian Archipelago. Phycologia 51: 347–357. DOI: 10.2216/10-26.1 Genetic information is proving to be important in conservation and management efforts that involve cryptic species and their role in native ecosystem restoration. Previous molecular studies have demonstrated that the red alga Spyridia filamentosa consists of several cryptic species. Spyridia filamentosa is considered to be a native species in Hawai‘i and was recently used in preliminary seagrass meadow restoration efforts in Maunalua Bay, O‘ahu. It became necessary to understand the genetic diversity of this species in the Islands and determine if there are relationships between any molecular clades of S. filamentosa and anatomical characters that might be useful (e.g. sediment capture) in habitat remediation. Both molecular and morphological (determinate branch cell dimensions) analyses revealed the presence of multiple S. filamentosa clades in Hawai‘i. Nuclear [partial LSU (large subunit)] sequence and determinate branch cell data recovered two broad lineages (I and II), which are known worldwide. The mitochondrial sequence (cox2-3 spacer) data further separated samples into five distinct clades and indicated that S. filamentosa arrived in Hawai‘i on at least six occasions. These results aided decisions made concerning preliminary experiments involved in seagrass habitat remediation and emphasized the importance of genetically evaluating cryptic species that are being considered for use in native ecosystem restoration or conservation.

A New Species of Kumanoa (Batrachospermales, Rhodophyta) from Kōke'e State Park, Kaua'i, Hawai'i

Abstract: A new freshwater red alga is described from Kōke‘e State Park on the island of Kaua‘i, Hawai‘i. The alga is a member of the genus Kumanoa, which was recently established to accommodate two sections of the large freshwater red algal genus Batrachospermum. Specimens are shown to be unique relative to all other confirmed members of the genus based on both morphological comparisons and molecular phylogenetic analyses of a concatenated alignment of three molecular markers. Kumanoa alakaiensis Sherwood, Jones, & Conklin, n. sp., differs from the only other known Hawaiian representative of the genus, K. spermatiophora, which is endemic to Maui, in having a much smaller, cartilaginous thallus; having reduced subspherical- to slightly obconicshaped whorls; and in lacking spermatiophores. Phylogenetic analyses support K. alakaiensis as a distinct and early diverging lineage within the genus, and as sister to a large clade containing all but three species characterized to date. This species description brings the total number of recognized freshwater red algal species in Hawai‘i to eight, three of which are believed to be endemic.

Tylotus laqueatus, a new species of Dicranemataceae (Gigartinales, Rhodophyta) from the Hawaiian Islands

A rarely collected shallow‐subtidal Hawaiian macroalga has been determined anatomically and molecularly to belong to an undescribed species of Tylotus J. Agardh, the most widely distributed genus of the small, mostly Australian‐endemic family Dicranemataceae. Thalli are repent and imbricate on calcareous boulders at the type locality on O‘ahu, and are anchored both basally and by haptera arising marginally and ventrally on the (sub‐)dichotomous, linear axes. Simple or forked terete haptera can be a means of perennation by the occasional direct issuing of adventitious blades. Fronds are multiaxial and consist of a broad pseudoparenchymatous medulla of thick‐walled cells surrounded on both sides by a two‐ or three‐layered small‐celled pigmented cortex in which numbers of ‘glandular’ hairs are embedded. Tetrasporangia are zonate, and gametophytes are monoecious. Carpogonial branches are three‐celled, directed to the thallus surface, and borne laterally on inner‐cortical supporting cells; cystocarps are prominently protuberant and scattered sparingly on dorsal frond surfaces, the carposporophytes directed outwardly beneath an ostiolate pericarp and connected to the parent gametophyte across a broad placental base in which the remnant auxiliary cell persists centrally. The inner surface of the pericarp is unusual in producing extensive patches or isolated islands of short gonimoblast filaments with terminal carposporangia as an apparent result of the implantation of gonimoblasts into the tissue of the lining. Anatomy indicates that the new species is more closely related to the East‐Asian Tylotus lichenoides Okamura than to the only other described member of the genus, the type species T. obtusatus (Sonder) J. Agardh from southern Australia. An rbcL phylogeny supports placement of sequences for Hawaiian specimens within the genus Tylotus but distinct from all previously recorded sequences of Tylotus. As is widely reported in other molecular‐phylogenetic analyses of the Gigartinales, we find that support for generic and familial relationships within the order is strong whereas that for between‐family relationships is low.