Algae Volume 21(1): 15-48, 2006 The Genus Martensia Hering (Delesseriaceae, Rhodophyta) with M. albida sp. nov. and M. flammifolia sp. nov. on Jeju Island, Korea Yongpil Lee Department of Life Science, Cheju National University, Jeju 690-756, Korea The genus Martensia (Delesseriaceae, Rhodophyta) is characterized by thalli composed of one to several blades that consist of proximal membranous sections and distal latticework. Nerves or veins are absent in the membranous sections. The life cycle of Martensia is accomplished by isomorphic alternation of generations. The gametophytes of Martensia are dioecious, and the male and female gametangial plants are morphologically similar. The type species of Martensia is M. elegans Hering. In this study, nine species were confirmed to occur in the subtidal regions of Jeju Island, Korea: M. albida sp. nov., M. australis Harvey, M. bibarii Y. Lee, M. elegans Hering, M. flammifolia sp. nov, M. fragilis Harvey, M. jejuensis Y. Lee, M. palmata Y. Lee, and M. projecta Y. Lee. Three of these, M. australis, M. fragilis, and M. elegans, are new records in the flora of Korea. The results of molecular analyses of the internal transcribed spacer (ITS) 1 region in the nrDNA showed that M. elegans is identical to M. australis, and M. fragilis coincides with M. bibarii. It may be a less effective tool for the species discrimination in Martensia. Key Words: Delesseriaceae, Martensia, M. albida, M. australis, M. elegans, M. fragilis, M. flammifolia Endlicher 1843), Mesotrema J. Agardh (1854), and INTRODUCTION Capraella De Toni (1936). Since the classification by Hering (1841), the genus The genus Martensia (Delesseriaceae, Rhodophyta) referred to as Martensia includes the following 16 species: was established on the basis of M. elegans Hering (1841) M. beccariana Zanardini (1878), M. denticulata Harvey from Port Natal, South Africa, and is characterized by (1855), M. flabelliformis Harvey ex J. Agardh (1863), M. the blades consisting of membranous parts and lattice- gigas Harvey (1863), and M. speciosa Zanardini (1874) work, the absence of microscopic veins or nerves on the from the South Pacific; M. australis Harvey (1855), M. ele- membranous parts, and reproductive structures that are gans Hering (1841), M. fragilis Harvey (1854), and M. indi- generally formed on the latticework. The monographic ca Krishnamurthy et Thomas (1977) from the Indian study of Martensia by Svedelius (1908) describes the Ocean; M. pavonia J. Agardh (1854) from the Atlantic genus in detail. Svedelius (1908) investigated the process Ocean; and M. lewisiae Lin, Hommersand et Fredericq of latticework formation, the structure of the latticework, (2004), M. formosana Lin, Hommersand et Fredericq and the reproductive structures. The tribe Martensiae (2004), M. bibarii Y. Lee (2004), M. jejuensis Y. Lee (2004), Wynne (2001) comprises three genera: Neomartensia M. palmata Y. Lee (2005), and M. projecta Y. Lee (2005) Yoshida et Mikami and Opephyllum Schmitz in Schmitz et from the North Pacific. De Toni (1900) reported M. becca- Hauptfleisch, and Martensia Hering, and is characterized riana and M. gigas as ‘species inquirendae,’ on which no by thalli with marginal growth, without nerves or veins, more records have been published to date. Recently, and with reticulate organization (Wynne 2001; Lin et al. Millar (1990) reported that M. speciosa and M. australis 2001b). Papenfuss (1950) clarified the nomenclature of are conspecific because the topotype collections of M. Martensia Hering (nom. cons.), although it was replaced speciosa were identical to the type collections and illustra- at one time by the generic names Hemitrema Brown (in tions of M. australis by Harvey (1855, p. 537; 1858, pl. 8). Millar (1990) also proposed that M. fragilis, M. pavonia, Corresponding author ([email protected]) and M. denticulata are conspecific because the lectotype 16 Algae Vol. 21(1), 2006 collections of these three species were identical in all tive cells was measured from the surface view. The thick- respects. Yoshida and Mikami (1996) established the new ness of the vegetative cells was measured from trans- genus Neomartensia on the basis of M. flabelliformis, which verse or longitudinal sections. The images of wet-pre- forms caposporangia in short chains and has vegetative served or pressed specimens were captured using a cam- cells that are irregularly arranged. However, the genus era (Nikon F2; Nikon, Tokyo, Japan) mounted on a Neomartensia was not widely accepted (Lin et al. 2004). photo-stand. All collections examined were deposited in On the other hand, Lin et al. (2001b) transferred the Herbarium of the Department of Life Science, Cheju Opephyllum martensii Schmitz in Schmitz et Hauptfleisch National University, Korea. (1897), which is the type species of the genus Opephyllum, Pieces of thalli from the dried herbarium sheets were to the genus Martensia on the basis of comparative mole- used for molecular analyses. The samples were frozen in cular analyses of both chloroplast-encoded rbcL and liquid nitrogen and stored at -70°C until DNA isolation. nuclear large-subunit ribosomal DNA (LSU rDNA). Total DNA was extracted using the SV Genomic DNA Consequently, eleven species of Martensia are currently Purification System (Promega, USA), according to the recognized. manufacturer’s instructions. The sequence boundaries of In Korea, Chyung and Park (1955) reported Martensia internal transcribed spacer (ITS) 1 regions were deter- denticulata Harvey at the Meeting of the Korean Society mined by comparing them to published sequences of of Biology in 1954 and gave it the Korean name various algae (Saunders et al. 1996; Freshwater et al. ‘Maltensi’. Latter, M. denticulata was reported from the 1999). The sequences were aligned using the program southern coast of Korea and Jeju Island (Rho 1958; Kang Clustal W (Thompson et al. 1994) and then adjusted man- 1960; Kang 1966; Kang 1968; Noda 1966, Lee 1976; Koh ually to align several conserved regions. Sites with miss- 1990; Lee et al. 1990; Lee and Koh 1991; Park et al. 1994). ing data or gaps were excluded from all analyses. Kang (1962) changed the Korean name for Martensia den- Sequence divergence among the taxa was calculated ticulata to ‘Bidanmangsa’ and this name is currently using the program DNADIST in PHYLIP 3.572 used. Recently, four new species of Martensia, i.e., M. (Felsenstein 1993), and the numbers of nucleotide substi- jejuensis Y. Lee, M. bibarii Y. Lee, M. palmata Y. Lee, and tutions were estimated using Kimura’s two-parameter M. projecta Y. Lee, have been described from Jeju Island, method (Kimura 1980). A transition/transversion ratio of Korea (Lee 2004; Lee 2005). This paper provides a diag- 2.0 was used. A bootstrap analysis of these data was nostic key for the nine species of Martensia that occur on done using 1000 resampled datasets, generated using the Jeju Islnad. SEQBOOT program (Felsenstein 1993), before calculating the distance matrices and neighbor-joining trees. The MATERIAL AND METHODS resulting matrices were subsequently subjected to maxi- mum parsimony analysis using the program DNAPARS Plants were collected in the subtidal region of Jeju (Felsenstein 1993). The program CONSENS in PHYLIP Island, Korea, between 2000 and 2004. All plants had was then used to construct a strict consensus tree. subtidal habitats and were therefore collected by scuba diving. The samples were kept in seawater during trans- RESULTS AND DISCUSSION port to the laboratory because they die easily and discol- or when exposed to air. The collected samples were Martensia Hering 1841: 92, nom. cons. immediately fixed in 5% formalin/seawater for 3-5 days. Martensia Hering 1841: 92; Kützing 1849: 888; Harvey Most of the fixed samples were prepared as dried 1855: 537; J. Agardh 1863: 825; De Toni 1900: 612; De Toni herbarium specimens. Sections of thallus were cut using 1924: 320; Papenfuss 1950: 182; Wynne 1983: 441; Millar a bench-top freezing microtome (MFS no. 222; Nippon 1990: 416; Yoshida and Mikami 1996: 101; Wynne 1996: Optical Works, Tolyo, Japan). Sections and parts of speci- 177; Womersley 2003: 95; Lin et al. 2001a. mens were mounted on glass slides in 50% corn syrup Synonyms: Hemitrema R. Brown in Endlicher 1843: 50. solution. Olympus research microscopes (BX50F(3, Mesotrema J. Agardh 1854: 110. Papenfuss 1942: 448. BX50F4; Olympus Optical Co., LTD, Japan) with photo- Capraella De Toni 1936. graphic apparatus (Olympus PM(C35DX, PM(P20, Opephyllum Schmitz in Schmitz et Hauptfleisch 1897: PM(20; Olympus Optical Co., LTD, Japan) were used to 410. (see Lin et al. 2001b: 595). observe the thalli. The length and breadth of the vegeta- Type species: M. elegans Hering 1841: 92. Lee: The Genus Martensia on Jeju Island 17 Korean name: Bidanmangsa (비단망사). host thallus. In M. albida, M. australis, M. elegans, M. for- Hering (1841) circumscribed the genus Martensia as mosana, M. fragilis, and M. lewisiae, the thalli consist of ‘Frons plana, areolata, avenia, margine fenestrata; fructus several blades that arise from the lower prostrating parts duplex; sphœrospermia longitudinaliter in reticulo simplici (Millar 1990; Lin et al. 2004). However, the thalli of M. serie disposita; capsulœ sphœricœ, reticulo affixœ, sporidia australis from Australia each consist of a single blade subglobosa foventes.’ It is estimated from the above (Millar 1990, fig. 52A). In M. palmata and M. projecta, the description that the thallus of Martensia consists of a thalli consist of several blades, but are easily segregated membranous section and latticework organization and into each blade because they may have no prostrating produces tetrasporangia and cystocarps on the lattice- blade. The thalli of M. flammifolia sp. nov. consist of a sin- work. Also, we assume that the gametophyte and gle blade each, although they grow in clusters as bunch- tetrasporophyte of Martensia are isomorphic. More es of blades. The thalli of Martensia generally have no recently, the genus Martensia has been circumscribed by stipes or stipe-like structures between the membranous the blades of the thallus partitioned into distal lattice- sections and the holdfasts.