title: CHARACTERIZATION OF MARTENSIA (DELESSERIACEAE, RHODOPHYTA) BASED ON A MORPHOLOGICAL AND MOLECULAR STUDY OF THE TYPE SPECIES, M. ELEGANS, AND M. NATALENSIS SP. NOV. FROM SOUTH AFRICA(1).
abstract: An examination of a series of collections from the coast of Natal, South Africa, has revealed the presence of two species of Martensia C. Hering nom. cons: M. elegans C. Hering 1841, the type species, and an undescribed species, M. natalensis sp. nov. The two are similar in gross morphology, with both having the network arranged in a single band, and with reproductive thalli of M. elegans usually larger and more robust than those of M. natalensis. Molecular studies based on rbcL sequence analyses place the two in separate, strongly supported clades. The first assemblage occurs primarily in the Indo-West Pacific Ocean, and the second is widely distributed in tropical and warm-temperate waters. Criteria that have been used in the past for separating the two, namely, the number and shape of the blades, the presence of a single- versus a multiple-banded network, and blade margins entire or toothed, were determined to be unreliable. Although the examination of additional species is required, the morphology and position of procarps and cystocarps, whether at or near the corners of the longitudinal lamellae and the cross-connecting strands or along the lobed, membranous edges of the longitudinal lamellae or on the thallus margins, may prove to be diagnostic at the subgenus level. We recognize subg. Martensia, including the type of Martensia: M. elegans and subg. Mesotrema (J. Agardh) De Toni based on Martensia pavonia (J. Agardh) J. Agardh.
authors.affiliation: Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan, ChinaDepartment of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USADepartment of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana 70504-2451, USAPhycology Research Group, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium.
authors.forename: Showe-Mei
authors.initials: SM
authors.lastname: Lin
authors.affiliation: Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan, ChinaDepartment of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USADepartment of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana 70504-2451, USAPhycology Research Group, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium.
authors.forename: Max H
authors.initials: MH
authors.lastname: Hommersand
authors.affiliation: Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan, ChinaDepartment of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USADepartment of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana 70504-2451, USAPhycology Research Group, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Fredericq
authors.affiliation: Institute of Marine Biology, National Taiwan Ocean University, Keelung 20224, Taiwan, ChinaDepartment of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USADepartment of Biology, University of Louisiana at Lafayette, Lafayette, Louisiana 70504-2451, USAPhycology Research Group, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium.
authors.forename: Olivier
authors.initials: O
authors.lastname: De Clerck
keywords: Delesseriaceae; Martensia; Martensia elegans; Martensia natalensis sp. nov.; Rhodophyta; subgenus Martensia; subgenus Mesotrema; systematics