• ALGAE
• /
• v.35 no.4
• /
• pp.337-347
• /
• 2020

Haraldiophyllum hawaiiense sp. nov. is described as a new mesophotic alga and a new genus record for the Hawaiian Islands. Six specimens were collected at a depth range of 81-93 m from Papahānaumokuākea Marine National Monument, and their morphology investigated, as well as molecular phylogenetic analyses of the plastidial ribulose-1,5-bisphosphate carboxylase-oxygenase large-subunit (rbcL) gene and a concatenated alignment of rbcL and nuclear large-subunit rRNA gene (LSU) sequences. Phylogenetic analyses supported H. hawaiiense sp. nov. as a distinct lineage within the genus Haraldiophyllum, and sister to a large clade containing the type species, H. bonnemaisonii, as well as H. crispatum and an undescribed European specimen. The six Hawaiian specimens were shown to be identical, but unique among other species of the genus as well as the recently segregated genus Neoharaldiophyllum, which comprises half of the species previously included in Haraldiophyllum. The vegetative morphology of H. hawaiiense sp. nov. resembles Neoharaldiophyllum udoense (formerly H. udoensis); however, no female or post-fertilization structures were found in the Hawaiian specimens to allow a more comprehensive comparison. The molecular phylogenies demonstrate that Haraldiophyllum is paraphyletic, suggesting either that the Myriogrammeae tribe includes undescribed genera, including Haraldiophyllum sensu stricto, or that Neoharaldiophyllum species should be transferred into the genus Haraldiophyllum. However, based on vegetative morphology and molecular analyses, and pending resolution of this taxonomic issue, the Hawaiian specimens are placed within the genus Haraldiophyllum. This new record for the Hawaiian Islands highlights the novel biodiversity from mesophotic depths, reaffirming the need for further investigation into the biodiversity of Mesophotic Coral Ecosystems.

• ALGAE
• /
• v.37 no.4
• /
• pp.249-264
• /
• 2022

Two genera of the Rhodymeniales, Halopeltis and Leptofauchea, are here reported for the first time from the Hawaiian Islands and represent the deepest records for both genera. Molecular phylogenetic analyses of cytochrome oxidase subunit I (COI), rbcL, and large subunit ribosomal DNA (LSU) sequences for Hawaiian specimens of Leptofauchea revealed one well-supported clade of Hawaiian specimens and three additional lineages. One of these clades is described here as Leptofauchea huawelau sp. nov., and is thus far known only from mesophotic depths at Penguin Bank in the Main Hawaiian Islands. L. huawelau sp. nov. is up to 21 cm, and is the largest known species. An additional lineage identified in the LSU and rbcL analyses corresponds to the recently described L. lucida from Western Australia, and is a new record for Hawai'i. Hawaiian Halopeltis formed a well-supported clade along with H. adnata from Korea, the recently described H. tanakae from mesophotic depths in Japan, and H. willisii from North Carolina, and is here described as Halopeltis nuahilihilia sp. nov. H. nuahilihilia sp. nov. has a distinctive morphology of narrow vegetative axes that harbor constrictions along their length. The current distribution of H. nuahilihilia includes mesophotic depths around W. Maui, W. Moloka'i, and the island of Hawai'i in the Main Hawaiian Islands. Few reproductive characters were observed because of the small number of specimens available; however, both species are distinct based on phylogeny and morphology. These descriptions further emphasize the Hawaiian mesophotic zone as a location harboring many undescribed species of marine macroalgae.

• Journal of Species Research
• /
• v.12 no.2
• /
• pp.180-188
• /
• 2023

The region of the marine environment between shallow waters and deep-sea (30-150 m in depth) is referred to as the twilight or mesophotic zone. This zone has been scarcely examined, as these depths are too shallow for safe submersible operation. Since 2018, a survey of mesophotic echinoderms in Korea has yielded many specimens of interest. In this study, we present two newly recorded echinoderms, Henricia irregularis and Parastichopus nigripunctatus based on morphological redescriptions with high-definition photographs and DNA barcoding data for P. nigripunctatus.

• Korean Journal of Environmental Biology
• /
• v.41 no.3
• /
• pp.291-297
• /
• 2023

This study introduces a newly discovered brittle star, Amphiophiura megapoma, from the mesophotic zone in the East Sea, Korea. It is the second species belonging to the genus Amphiophiura (which includes 57 species) to be recorded in Korean waters after A. sculpta. The specimen was discovered during a September 2022 survey, by SCUBA diving in the upper mesophotic zone of the East Sea, Korea. This study presents the morphological characteristics of A. megapoma, highlighting its differences from the related species within a comprehensive taxonomic description. It provides high-resolution images of A. megapoma and a taxonomic key for Amphiophiura species in Korea.

• ALGAE
• /
• v.35 no.2
• /
• pp.145-155
• /
• 2020

Specimens of red algae corresponding to the peyssonnelioid genus Sonderophycus were collected at Kure Atoll, Hawai'i, at a depth range of 88-94 m depth during mesophotic surveys of the Papahānaumokuākea Marine National Monument, Hawaiian Islands, and were analyzed using morphological and molecular approaches. Analyses of mitochondrial cytochrome oxidase subunit 1 and chloroplast rbcL DNA sequences demonstrated that the Hawaiian specimens were identical to one another yet distinct from the three other species currently recognized within the genus (S. capensis [Montagne] M. J. Wynne, S. coriaceus [Womersley & Sinkora] M. J. Wynne, and S. fervens Dixon), as well as the likely congener, Peyssonnelia caulifera Okamura, and are proposed here as a new species: Sonderophycus copusii A. R. Sherwood. Sonderophycus copusii is morphologically distinct from other members of the genus by the following combination of characters: the presence of occasional secondary perithallial growth, emergence of rhizoids from the hypobasal cuticle at a strongly acute angle, a lack of horizontally directed filaments in the lower perithallus, and the lack of a stipe. This is the first record of the genus Sonderophycus in the Hawaiian Islands. Sonderophycus copusii was documented as a dominant member of the algal community at Kure Atoll, and thus may play a significant ecological role in the deep-water benthic community of Kure Atoll, along the lines of reports of deep water peyssonnelioid beds in the Mediterranean, Red Sea, and Caribbean. This study further highlights the unexplored diversity of the Peyssonneliales in Hawai'i, and emphasizes more generally the degree of as yet undiscovered biodiversity of algae at mesophotic depths.

• ALGAE
• /
• v.35 no.4
• /
• pp.349-359
• /
• 2020

Specimens of Umbraulva with greenish iridescent were collected in the subtidal zone of Jeju Island, Korea. To investigate these collections, plastid rbcL and tufA sequencing of six greenish iridescent specimens, including four Umbraulva japonica, were analyzed. Phylogenetic analysis of a concatenated multigene alignment found that the greenish iridescent specimens belonged to a yet undescribed taxon in the genus Umbraulva. We herein propose the name Um. yunseulla sp. nov. for this specimens. Juveniles of Um. yunseulla sp. nov. resemble the generitype Um. japonica in appearance, showing globular to subglobular and funnel-shaped habits, but the blades of this new species are not split longitudinally like those of Um. japonica. Although the multigene phylogenetic tree showed the polyphyletic clade of Umbraulva with respect to the genus Ryuguphycus, Um. yunseulla sp. nov. formed a clade with Um. japonica and Um. amamiensis by weak bootstrap support. These findings, Um. yunseulla sp. nov., highlight the importance of studying the biodiversity of subtidal habitats from Jeju Island, Korea and further emphasize the need for investigations of macroalgae in the mesophotic zone around the Korean peninsula.