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

Abstract

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.

Taxonomic Transfer of the Red Algal Genus Gloiosaccion to Chrysymenia (Rhodymeniaceae, Rhodymeniales), Including the Description of a New Species, Chrysymenia pseudoventricosa, for the Gulf of Mexico

“…Towards this goal, chloroplastencoded rbcL, the Universal Plastid Amplicon (UPA), and nuclear large subunit ribosomal DNA (LSU) markers were selected due to their power in the resolution below, at and above (e.g., Fredericq et al 2003, Sherwood et al 2010, Lin et al 2012) the species level within the red algae.…”

“…Additional gene-specific primers for Rhodymeniaceae were newly designed for PCR amplification (Table 2). A portion of LSU rDNA and UPA were also amplified and sequenced using the primers and PCR protocol referenced in Sherwood et al (2010). PCR products were gel-purified and sequenced in-house on both directions using the BigDye tm Terminator v. 3.1 (Life Technologies Grand Island NY, USA) on a ABI 3130xl Genetic Analyzer.…”

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

“…PCR for CO1 was conducted using the primers referenced in Saunders (2005) with an initial denaturation at 94°C followed by 40 cycles at 94°C for 1 min (denaturation), 45°C for 1 min (primer annealing), and 72°C (extension) for 1 min followed by a final extension at 72°C for 5 min. PCR for a portion of the nuclear encoded LSU was performed using the primers and PCR protocol referenced in Sherwood et al (2010). Resulting PCR products were either sequenced in-house at the UL Lafayette campus on an ABI Model 3130xl Genetic Analyzer or were outsourced (Beckman Coulter Genomics Danvers, MA).…”

“…A concatenated gene dataset including psbA, CO1 and LSU was assembled using the application Sequence Matrix 1.7.8 (Vaidya et al 2011). DNA sequences from the Sporolithaceae (Sporolithales) (one taxon) and Hapalidiaceae (Corallinales) (one taxon) were used as the outgroup, and DNA sequences from nineteen specimens comprising 16 taxa belonging to the Lithophylloideae were included in the ingroup (Bittner et al 2011, Sherwood et al 2010. The final concatenated dataset was 1,818 base-pairs in length including a 589 base-pair portion of psbA, a 663 base-pair portion of CO1 and a 566 base-pair portion of LSU (see Table 1 for a list of samples included in the phylogenetic analysis).…”

Molecular diversity and morphology of the genus Actinotrichia (Galaxauraceae, Rhodophyta) from the western Pacific, with a new record of A. robusta in the Andaman Sea

“…Subsequently, 2005, Wang et al 2005, Liu and Wang 2009. Recently, mitochondrial cox1 gene has been used for identification of red algae (Saunders 2005, Geraldino et al 2006, Sherwood et al 2010, and only two cox1 sequences of A. fragilis are to date registered in GenBank. Together with morphological observations, we employed both rbcL and cox1 gene sequencing so as to provide a better understanding of genetic and species diversity in Actinotrichia. )…”