Boo Yeon Won

Neosiphonia peruviensis sp. nov. (Rhodomelaceae, Rhodophyta) from the Pacific coast of South America

Abstract Approximately 29 species of Neosiphonia are currently recognized worldwide. We describe our unidentified samples collected from the Pacific coast of South America as a new species, N. peruviensis sp. nov., based on morphological and molecular data. Neosiphonia peruviensis sp. nov. is characterized by erect and prostrate thalli, rhizoids cut off from proximal ends of pericentral cells by cross walls, six pericentral cells that are totally ecorticate, abundant trichoblasts forked once or twice, prominent scar cells and tetrasporangia spirally arranged. Our new species is similar to several Neosiphonia/Polysiphonia species having more than four pericentral cells: N. notoensis, N. porrecta, “N. tepida”, N. teradomariensis, and “P. forfex”. However, N. peruviensis sp. nov. is distinguished from these similar species by having six pericentral cells through all of the thallus. Phylogenetic analyses of rbcL indicate that our N. peruviensis is placed in genus Neosiphonia and is also distinguishable from other Neosiphonia species.

Polysiphonia dokdoensis sp. nov. (Rhodomelaceae, Ceramiales) based on a population previously known as Polysiphonia atlantica sensu Kim and Lee from Korea

Abstract The genus Polysiphonia Greville is characterized by having four ecorticated pericentral cells, rhizoids in open connection with the pericentral cells, four-celled carpogonial branches, spermatangial branches replacing the whole trichoblast, and tetrasporangia in straight series. Polysiphonia dokdoensis sp. nov. collected from Dokdo, Korea is here described as a new species on the basis of morphological and molecular data. Polysiphonia dokdoensis is characterized by having four ecorticated pericentral cells, unicellular rhizoids in open connection with pericentral cells, scar cells placed between two pericentral cells, an alternating arrangement of unilateral branch pairs, and tetrasporangia in straight series. The alternating arrangement of unilateral branch pairs and the placement of the scar cell between two pericentral cells are recognized as main characters to identify P. dokdoensis. Polysiphonia dokdoensis is morphologically identical to “P. atlantica” sensu Kim and Lee, which is now recognized as P. dokdoensis sp. nov. and distinguished from the authentic European P. atlantica by the distinguishing morphological character states. Phylogenetic analyses of rbcL confirm the placement of the new taxon as a distinct species in Polysiphonia sensu stricto.

Wilsonosiphonia gen. nov. (Rhodomelaceae, Rhodophyta) based on molecular and morpho-anatomical characters

Morphological, anatomical, and molecular sequence data were used to assess the establishment and phylogenetic position of the genus Wilsonosiphonia gen. nov. Phylogenies based on rbcL and concatenated rbcL and cox1 loci support recognition of Wilsonosiphonia gen. nov., sister to Herposiphonia. Diagnostic features for Wilsonosiphonia are rhizoids located at distal ends of pericentral cells and taproot‐shaped multicellular tips of rhizoids. Wilsonosiphonia includes three species with diagnostic rbcL and cox1 sequences, Wilsonosiphonia fujiae sp. nov. (the generitype), W. howei comb. nov., and W. indica sp. nov. These three species resemble each other in external morphology, but W. fujiae is distinguished by having two tetrasporangia per segment rather than one, W. indica by having abundant and persistent trichoblasts, and W. howei by having few and deciduous trichoblasts.

Polysiphonia freshwateri sp. nov. and Polysiphonia koreana sp. nov.: two new species of Polysiphonia (Rhodomelaceae, Rhodophyta) from Korea

Polysiphonia sensu lato comprises approximately 200 species, which are currently assigned to several different genera. To date, one of these genera, namely, Polysiphonia, has been reported to have 17 species. Here, we describe for the first time P. freshwateri sp. nov. and P. koreana sp. nov. from Uljin and Ulleung Island, Korea, based on morphological and molecular evidence. Polysiphonia freshwateri sp. nov. and P. koreana sp. nov. are characterized by having the typical Polysiphonia features. Polysiphonia freshwateri sp. nov. is further characterized by having abundant trichoblasts, conspicuous scar cells, and tetrasporangia arranged in spiral series. Polysiphonia koreana sp. nov. is further characterized by having very scarce scar cells placed between two pericentral cells, from which cicatrigenous branches arise. The results of our rbcL sequence analyses support the taxonomic placement of P. freshwateri sp. nov. and P. koreana sp. nov. within Polysiphonia.

Neosiphonia baliana sp. nov. and N. silvae sp. nov. (Rhodomelaceae, Rhodophyta) from Bali, Indonesia

Abstract Worldwide, 32 species have been recognized in the genus Neosiphonia. We describe two new species of the genus from Bali, Indonesia, based on morphological and molecular data. Neosiphonia baliana sp. nov. is recognized by having rhizoids cut off from the proximal end of pericentral cells, axes with five pericentral cells, axes ecorticate throughout, the absence of trichoblasts and scar cells, the straight arrangement of tetrasporangia, and spermatangia arising from a basal cell without the production of trichoblasts. Neosiphonia silvae sp. nov. is characterized by having rhizoids cut off from the proximal end of pericentral cells, axes with four pericentral cells, axes ecorticate throughout, production of abundant trichoblasts near the apices, prominent scar cells, an exceedingly prominent apical cell at axis tips, and one or two tetrasporangia per branch. Phylogenetic analyses of rbcL indicated that our N. baliana sp. nov. and N. silvae sp. nov. fall in the genus Neosiphonia, and we distinguish them on the basis of morphological features from other congeneric species.

First record of Neosiphonia echinata (Rhodomelaceae, Rhodophyta) in the South Pacific: an introduced species in Southeast Asia.

Abstract Neosiphonia echinata, a well-known western Atlantic species, is here reported for the first time from Indonesia and this extends its distribution into Southeast Asia. Neosiphonia echinata was collected from Sulawesi, Indonesia as an epiphyte on Kappaphycus alvarezii and growing on ropes in a culture farm. We also collected this species from Florida, USA, and then compared their morphology and molecular data. Neosiphonia echinata is identified by having erect main filaments arising from prostrate filaments, numerous rhizoids cutting off from the proximal end of pericentral cells by a cross wall, four pericentral cells throughout the thallus, ecorticate axes, very long and abundant trichoblasts more than twice forked, abundant adventitious laterals, procarps with four-celled carpogonial branches, and a spiral arrangement of tetrasporangia. Our phylogenetic analyses of rbcL and cox1 indicate that N. echinata found in Indonesia was very closely related to material from the Western Atlantic Ocean. Neosiphonia echinata may be added as an introduced species to the Indonesian marine flora. The shipping routes western Atlantic-Mediterranean-Indonesia and western Atlantic-Pacific Ocean-Indonesia might be considered as possible pathways of introduction as a consequence of ballast water and hull fouling.

Two new species of Centroceras (Ceramiaceae, Rhodophyta) from KwaZulu-Natal, South Africa

Two distinct species of Centroceras from South Africa that were previously referred to as Centroceras sp. 2 and Centroceras sp. 3 on the basis of comparative rbcL sequence analysis are here newly described on the basis of vegetative morphology. Centroceras hommersandii sp. nov. is characterized at the nodes by an elongated cortical cell derived from the second cortical initials, a flattened gland cell and a cortical cell cut off from the first cortical initials, straight spines, 13–14 periaxial cells, and by tetrasporangia not associated with involucral branchlets. Centroceras natalensis sp. nov. is characterized at the nodes by an ovoid cortical cell on the second cortical initial, a flattened gland cell and a cortical cell produced from the first cortical initial, straight spines, and 12–14 periaxial cells. Other species of Centroceras examined possess either only a flattened gland cell cut off from the first cortical initials (in C. clavulatum, C. rodmanii, C. tetrachotomum), or an ovoid gland cell with a cortical cell (in C. gasparrinii, C. hyalacanthum, C. internitens, C. micracanthum). Centroceras hommersandii sp. nov. is also distinguished by an elongated acropetal cortical cell formed only on the second cortical initial, whereas other species (C. hyalacanthum, C. internitens, C. micracanthum) have elongated acropetal cells present on both the first and second cortical initials. A key to the South African species of Centroceras is provided.

Wynneophycus geminatus gen. & comb. nov. (Delesseriaceae, Rhodophyta), based on Hypoglossum geminatum Okamura

Abstract: Wynneophycus gen. nov. (Delesseriaceae, Ceramiales) is a new monotypic genus based on Hypoglossum geminatum Okamura, a species originally described from Japan. Wynneophycus geminatus (Okamura) comb. nov. is characterized by a discoid holdfast, erect or decumbent monostromatic blades with percurrent midribs, production of new blades from the midrib axial cells and absence of microscopic veins. In addition, it has apical cell division, several orders of lateral cell rows and paired transverse periaxial cells and formation of second-order cell rows from lateral cells with all forming third-order cell rows, with the midrib becoming corticated and forming a subterete stipe below as the blade wings are lost. Distinctive features of the new genus include tetrasporangia initiated from and restricted to single rows of second-order cells arranged in a single layer, cover cells developing prior to the tetrasporangia and an absence of intercalary cell divisions. Phylogenetic analyses of rbcL and large-subunit rDNA sequence data support the separation of Wynneophycus from Hypoglossum. We herein report on W. geminatus gen. & comb. nov. and delineate the new tribe Wynneophycuseae within the subfamily Delesserioideae of the family Delesseriaceae.

Morphology and phylogeny of Craspedocarpus jindoensis sp. nov. (Cystocloniaceae, Gigartinales) from Korea

Abstract: Craspedocarpus has seven currently described species from the western Atlantic and South Pacific Oceans. The genus is characterized by well-developed rosettes of small outer cortical cells, marginal proliferations, discoid holdfasts, carposporophytes with several large central cells and zonate tetrasporangia. Craspedocarpus jindoensis sp. nov. collected from Jindo, Korea, is here described as a new species on the basis of morphological and molecular data. The new species is characterized by having fan-shaped thalli, smooth margins, subdichotomous branching pattern, incomplete pseudoparenchymatous medulla with filaments, and tetrasporangial sori and cystocarps both in fronds and proliferations. Phylogenetic analysis of rbcL also placed C. jindoensis sp. nov. in Craspedocarpus and distinguished it from congeners. The sequence divergences between C. jindoensis sp. nov. and the other species of Craspedocarpus, C. erosus, C. tenuifolius and C. venosus are 2.9%–3.2%, respectively.

Morphology and phylogeny of Pterosiphonia dendroidea (Rhodomelaceae, Ceramiales) described as Pterosiphonia tanakae from Japan

Abstract Recent phylogenetic studies of the genus Pterosiphonia suggest that Pterosiphonia dendroidea and Pterosiphonia tanakae are conspecific and show its wide geographic distribution in the Pacific. Pterosiphonia dendroidea was originally described as Polysiphonia dendroidea from Peru and later transferred to Pterosiphonia. Pterosiphonia dendroidea was characterized by diagnostic features such as its light cortication, the presence of trichoblasts, 8–12 pericentral cells, branches with the production of 3- to 5-order laterals, and congenital fusion of 2–3 segments. Pterosiphonia tanakae shares these features. Our phylogenetic analysis using rbcL sequences reveals a low gene sequence divergence (0.5%–0.7%) between the samples of P. dendroidea and P. tanakae. We propose that P. tanakae is a later synonym of P. dendroidea, and our study indicates the wide distribution of P. dendroidea in the northern and the southern Pacific Ocean.