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Valeriemaya gen. nov. (Rhodophyta), with a discussion of apical organization within the Delesseriaceae
Abstract
Valeriemaya gen. nov. is described from subtidal habitats along the New South Wales coast of eastern Australia and assigned to the red algal family Delesseriaceae. Valeriemaya geminata sp. nov., designated the generitype, and V. maculata sp. nov. are assigned to this genus. Plants in both species form a small component of the turf community of the rocky reef flora, occurring from the lowest littoral to a death of 20 m. They consist of clusters of mostly simple, lanceolate blades arising from holdfasts that may be discoid or well-developed, spreading systems of terete, branched axes firmly clasped to the substratum. V. geminata is distinctive in having a pair of ovate tetrasporangial sori mid-way along the erect blades, a habit in which erect blades recurve toward the substratum, attaching by means of rhizoidal tufts and producing new blades, and in its lack of vesicular cells, whereas V. maculata is distinctive in having single, large, ovate, tetrasporangial sori located at the bases of the blades, a habit in which the erect blades do not become attached to the substratum at their distal ends, and in having prominent vesicular cells. Sexual plants are described for V. geminata. The scattered nature of the procarps shows that the genus belongs in the Nitophylloideae. Male plants bear spermatangial sori in irregular rectangular patches separated by sterile cells. The apices are diagnostic in having single, transversely divided apical cells and second-order cell rows producing third-order cell rows adaxially. The apical organization in this species closely resembles that in certain other taxa of this family which had previously been allied with the Phycodrys and Pollexfenia groups of Nitophylloideae. Evidence is presented to support the delineation of a new type of apical organization (the Valeriemaya-type) which warrants its own group (the Valeriemaya group) and which is distinguishable from that of the Phycodrys group.
... The Yendonia group was merged with the Phycodrys group. Wynne (1996) published a revised key to genera of Delesseriaceae together with a list of the genera, type species, and recent references and added the Valeriemaya group (Millar and Wynne 1992) to the subfamily Nitophylloideae based on the presence of a persistent apical cell. Three tribes have been proposed or emended since 1996: the Dicroglosseae (Millar and Huisman 1996), the Myriogrammeae (Hommersand and Fredericq 1997a), and the Schizoserideae (Hommersand and Fredericq 1997b) (Table 1). ...
... The tribe is problematic when one considers the range in morphologies of the included genera, with Hemineura having been placed in the Hemineura group; Patulophycus, Marionella, and Laingia in the Delesseria group; Botryocarpa in the Botryocarpa group; and Pseudophycodrys in the Pseudophycodrys group (Kylin 1956, Wynne 2001. The procarps in Hemineura contain two carpogonial branches and two sterile groups (Lin et al. 2001), whereas the other genera appear to have typical procarps with one carpogonial branch and two sterile groups as in Delesseria (Fig. 6B) (Wagner 1954, Edding 1982, Millar and Wynne 1992. Branching is exceedingly variable among the genera of Hemineureae, tak- ing place from the midrib, macroscopic nerves, margins or surfaces of the blades; however, the blades are polystromatic except at the margin in all of the species. ...
The current system of classification of the Delesseriaceae rests largely on Kylin's treatment which encompass the subfamilies Delesserioideae with five ‘Groups’ and Nitophylloideae with six ‘Groups’. In this study we test the Kylin system based on phylogenetic analyses inferred from two molecular data sets and morphological evidence. A total of 145 delesseriacean taxa worldwide were sequenced for chloroplast-encoded rbcL, and 82 taxa for the nuclear-encoded large subunit ribosomal RNA gene (LSU). Three large clades are identified in the combined data sets, one of which corresponds to the Delesserioideae, one to a narrowly circumscribed Nitophylloideae, and the third to a new subfamily comprising the remainder of the Nitophylloideae sensu Kylin. Belonging to the Delesserioideae are an expanded Hemineura group that includes Hemineura, Patulophycus, Marionella, Laingia, Botryocarpa and possibly Pseudophycodrys, a Caloglossa group, a Hypoglossum group that includes Hypoglossum, Branchioglossum, Bartoniella, Zellera, Phitymorphora, and Chauviniella, a Delesseria group with Delesseria, Membranoptera and possibly Grinnellia (but not Apoglossum) and most southern hemisphere species of Delesseria which are properly placed in Paraglossum J. Agardh 1898. The revised Nitophylloideae contains Nitophyllum, Valeriemaya, Polyneuropsis, Calonitophyllum and also Martensia and Opephyllum. The unnamed subfamily includes the Phycodrys group with Phycodrys and Polyneura, the Cryptopleura group with species placed in Cryptopleura, Hymenena, Acrosorium and Botryoglossum, the Myriogrammeae with Myriogramme and Haraldiophyllum, and the Schizoserideae with Schizoseris, Neuroglossum, Drachiella, Abroteia, and South American species of Platyclinia. This research promotes the correlation of molecular and morphological phylogenies with biogeographic hypotheses for the family.
... The quasi-ubiquitous presence of apical cells and apical meristems across major lineages and ploidy levels of life cycle phases (e.g. [30][31][32]33 ]) suggests that an intimate association between longitudinal polarity and apical meristems is a fundamental property of growth in photosynthetic multicellular eukaryotes. Although the embryos of all extant embryophytes have well-defined longitudinal polarity, it is unclear whether embryonic growth from an apical cell was established very early in embryophyte evolution. ...
... Microscope slides were mounted in a mixture of 20% Karo ® Syrup (ACH Foods, Memphis, Tennessee, USA) and 80% distilled water. Some specimens were previously stained with aniline blue, while others were mounted in a mixture of 1% aniline blue, 1% acetic acid, 50% Karo ® Syrup and 48% distilled water (Millar & Wynne, 1992). Sections for microscopic observations were made by hand using a razor blade. ...
Sand-covered rocks provide a particular habitat to benthic seaweeds, which must
tolerate the stressful conditions imposed by the presence of sediments. Turf assemblages are
dominant in this habitat, which is widely distributed along the Atlantic Iberian Peninsula,
neverthelss their flora remained poorly known. This work presents a taxonomic, floristic
and chorological account of the most representative Rhodomelaceae from sand-covered
rocks along the Atlantic Iberian Peninsula. For each species we provided morphological
descriptions, distribution maps, and/or COI-5P sequences, as well as taxonomic notes. The
species studied are: Chondria coerulescens, Ctenosiphonia hypnoides, Herposiphonia cf.
secunda f. tenella, Leptosiphonia schousboei, Lophosiphonia reptabunda, L. simplicissima
sp. nov., Ophidocladus simpliciusculus, Polysiphonia caespitosa, P. devoniensis, P. foeti-
dissima, P. fucoides, P. nigra, P. stricta, P. tripinnata, Pterosiphonia ardreana, P. parasitica,
P. pennata and Streblocladia collabens. Among our taxonomical conclusions, we herein
proposed a novel species Lophosiphonia simplicissima as well as the transfer of Streblo-
cladia collabens to the genus Neosiphonia. Furthermore, the parasitic species Aiolocolax
pulchellus is described and its taxonomic position is discussed.
Papenfussia japonica (Yoshida et Mikami) M.J. Wynne, currently recognized as a Japanese endemic species, is characterized by a polystromatic thallus, a transversely dividing apical meristematic cell, intercalary cell division in primary and higher-order cell rows, and a Papenfussia-type procarp comprising a four-celled carpogonial branch, a supporting cell, and a single-celled sterile cell group with no cover cell group. We collected specimens from the southern coast of Jeju Island, Korea, that matched the original description in all respects other than female reproductive structures: Korean plants had Nitophyllum-type procarps with a cover cell group. The developmental pattern of female reproductive structures and the rbcL gene data indicate that P. japonica has a close relationship with the recently described genus Augophyllum Lin, Fredericq et Hommersand even though the apical organization of P. japonica differs from that of Augophyllum. We here transfer P. japonica to the genus Augophyllum.
A red alga that had previously been known from South Africa under the name 'Erythroglossum sp.' is recognised to represent a new species of Valeriemaya: V. seagriefii sp. nov. Collections of this alga occurring in the lower intertidal and subtidal habitats of rocky shores have been made from both the Eastern Cape and Western Cape Provinces. This represents the first report of the genus Valeriemaya from Africa. Previously, the genus, characterised by its typical apical organisation, monostromatic blades, an ill-defined midrib region, and the absence of microscopic nerves or veins, has been known with certainty only from eastern Australia. Valeriemaya seagriefii is delineated from the two previously known species of the genus by the overall size of the blades, the location of sporangial sori, the absence of gland cells, and blades which do not recurve towards the substratum to become attached and give rise to new blades. Valeriemaya seagrieffii has been collected from Glencairn, False Bay to Hluleka in the Eastern Cape Province.
The Algae Nova-Zelandicae Exsiccatae were distributed by Victor W. Lindauer between 1939 and 1953, in fourteen fascicles, each consisting of 25 sheets. The Exsiccatae have served as a reference set of New Zealand algae in both national and international institutions. Taxonomic studies of New Zealand algae have been based on material from the Exsiccatae. This list presents the names of the specimens at the time they were distributed in the ANZE, their current names, and notes about the status of particular specimens. Thirty eight of the 350 sheets have some level of type status (i.e., iso-, isolecto-, para-, syntype).
Hemineura is endemic to Australia and the sole member of the 'Hemineura-Gruppe', an informal taxon, equivalent to a tribe, that Kylin defined primarily by its bicarpogonial supporting cells. We have found that supporting cells carry not only two carpogonial branches but also two sterile groups, a type of procarp not known for any other member of the family Delesseriaceae or the order Ceramiales. The closely related genera Patulophycus, Marionella and Laingia all have monocarpogonial procarps, suggesting that the procarp of Hemineura is a uniquely derived feature. Our observations reveal that transverse intercalary cell divisions interpolate cells within cell rows and horizontal or oblique intercalary cell divisions intersect between cell rows, maintaining the branching pattern within an expanding blade. A comparison of morphological features, combined with molecular studies to be published elsewhere, strongly suggests that the genera Hemineura, Patulophycus, Marionella, Laingia, Botryocarpa, Pseudophycodrys and, possibly, Microrhinus (genera that were formerly placed in the Delesseria-, Botryocarpa- or the Pseudophycodrys-groups) all belong to a southern-hemisphere assemblage with polystromatic blades, for which the tribe Hemineureae S.M. Lin, Hommersand & Kraft trib. nov. is proposed.
Haraldiophyllum infossum sp. nov. is a small red alga that is partially buried by sponges and ascidians in the turf community often under stands of Ecklonia radiata (C. Agardh) J. Agardh. Blades are monostromatic with conspicuously dentate margins and arise from creeping stolons. Spermatangial and tetrasporangial sori form elongate, interrupted patches along the mid-region of the blades. Features allying the new species with the genus Haraldiophyllum include growth by means of many marginal initials, blades that are monostromatic except at their base and where reproductive structures are borne, absence of microscopic veins, procarps that are scattered over the surface of the fertile frond and which are associated with two groups of sterile cells and one group of cover cells, and carposporangia that are borne singly and terminally on gonimoblast filaments. Also important is the presence of a carposporophyte fusion cell that incorporates gametophytic cells of the floor of the cystocarp cavity. The supposed difference in orientation of the two periaxial cells relative to the longitudinal axis of the frond (mostly parallel in Haraldiophyllum and mostly perpendicular in Nitophyllum) is argued to be of little taxonomic significance. The only two characters which indisputably separate the genera are shown to be the number of sterile cell groups in the procarps and the fusion-cell anatomy. Similarities between the procarps of Haraldiophyllum and Hideophyllum, in which cover cells are present, are discussed in relation to those of the closely related genera Calonitophyllum, Nitophyllum, Myriogramme and Valeriemaya.
All published, and many unpublished, records of marine and freshwater red algae from the New South Wales mainland and Lord Howe Island are brought together for the first time. Of the 381 species listed (in 14 orders, 41 families and 174 genera), some 22% have New South Wales type localities (58 from the mainland and 24 from Lord Howe Island) and the remainder are either typically southern Australian, Queensland, or much more widely distributed. Twenty-five percent (100) of the species and 20% (35) of the genera are newly recorded for the New South Wales coast, one genus (Callithamniella) is new to the Pacific Ocean, and two (Ditria and Titanophora) are newly recorded for Australia. The new combination Gloiocladia minutula is also proposed. All nomenclature is updated and relevant synonyms and misapplied names are included.
Nitophyllum erosum Harvey (Delesseriaceae, Rhodophyta) is a branched, monostromatic red alga that is readily recognised by its distinctive fringe of branched, multicellular processes. It has been considered to be a member of the genus Myriograrnrne Kylin, since it was thought to have carposporangia borne in short chains, a feature partially diagnostic for that genus. Recent collections of female and cystocarpic material have allowed us to ascertain the structure of the procarp, a feature important in generic placement. The procarp includes two periaxial cells, of which one acts as a cover cell while the other functions as the supporting cell, ultimately bearing two sterile cell groups and a four-celled carpogonial branch. In addition, the carposporophyte includes a distinctive fusion cell that incorporates gametophytic cells from the floor of the cystocarpic cavity, and the carposporangia are single and terminal on gonimoblast filaments. This combination of characters is diagnostic of the genus Haraldiophyllurn, a genus to which we transfer this species as Haraldiophyllum erosurn (Harvey) Millar & Huisman. comb. nov.
The temperate marine red algal flora of the North Atlantic Ocean contains two principal components: a former Arctic flora, and the remnant of a mid- to late-Tethyan flora. The problem for the biogeographer is to determine how these floras were assembled and subsequently modified. My evaluation is based on an analysis of morphological characters that define family clusters, families, genera and infrageneric taxa among Rhodophyta. The following scenario is suggested by these observations.
Phylogenetic lines that evolved in the Tethyan Ocean in the Mesozoic became widely distributed, largely through plate tectonics and seafloor spreading. Their descendants presently have major centers of dispersal in the SW Pacific (Australia, New Zealand) and the NW Pacific (NE Asia and Japan). Concomitant with gradual cooling of the oceans beginning in Cretaceous and accelerated cooling since Oligocene, a flora evolved within the Tethyan Ocean composed mainly of new phylogenetic lines. With the gradual collapse of the Tethyan Seaway in the Neogene, a portion of that flora, including many archtypal species, was isolated in the NE Atlantic. The larger component in the western Tethys evolved through adaptation to high levels of predation by herbivores. Taxa that had evolved earlier retreated to temperate waters nearer the poles. One refugium for this older element was the Arctic Ocean which received taxa from the west (N Pacific), and from the southeast (via the Turgai Strait and west Siberian Sea). The completion of the Bering Land Bridge, possibly in Eocene, isolated the Arctic flora from the influence of the N Pacific. Extension of the mid Atlantic ridge system to the Arctic Ocean ultimately brought the Arctic flora into contact with the N Atlantic flora, probably in Oligocene. Some components of this flora underwent bipolar distribution in the Atlantic reaching South America, Antarctica and islands of the the West Wind Drift Extinction of many N Atlantic taxa in the Neogene was followed by the addition of new elements that evolved in the Indo-W Pacific, migrated around South Africa, and were added either by amphitropical distribution along the coast of West Africa or through long range dispersal by way of the Caribbean Sea. A few N Pacific species appear to have reached the N Atlantic since the opening of the Bering Strait in Pliocene.
Predaea kraftiana sp. nov. is described from the subtidal in the vicinity of Coffs Harbour in northern New South Wales on the east coast of Australia. Thalli are reniform when young, flabellate and lobed when mature; outer cortical cells are cylindrical, the cortical fascicles being pseudodichotomously branched; vesicular cells are absent; carpogonial branches are generally three cells long, but may be two-, four-or five-celled, with an ampulliform basal cell generally bearing a small, sterile cell similar in morphology to the nutritive cells found on cells in the vicinity of auxiliary cells; fertilized carpogonia divide once transversely, each of the resulting cells forming up to three connecting filaments; gonimoblast initials are produced on the lateral surface of the auxiliary cell opposite the site of connecting filament juncture. In culture, carpospores from field-collected gametophytes developed into crustose plants lacking cell fusions or secondary pit-connections. Irregularly to regularly zonately cleaved tetrasporangia were formed on irregularly branched erect filaments at 24°C, 14:10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h. Monosporangia were also formed terminally on these filaments. At 24°C, 14: 10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h, tetraspores from cultured plants germinated to form small, spherical, gelatinous gametophytes which produced carpogonial branches and spermatangia identical to those found on field-collected plants. Spermatia were not seen attached to trichogynes, auxiliary cells did not develop, and no carposporophytes were produced. Monospores probably formed further tetrasporophytes. The species thus appears to have a Bonnernaisonia hamifera-type life history.
Predaea kraftiana sp. nov. is described from the subtidal in the vicinity of Coffs Harbour in northern New South Wales on the east coast of Australia. Thalli are reniform when young, flabellate and lobed when mature; outer cortical cells are cylindrical, the cortical fascicles being pseudodichotomously branched; vesicular cells are absent; carpogonial branches are generally three cells long, but may be two-, four-or five-celled, with an ampulliform basal cell generally bearing a small, sterile cell similar in morphology to the nutritive cells found on cells in the vicinity of auxiliary cells; fertilized carpogonia divide once transversely, each of the resulting cells forming up to three connecting filaments; gonimoblast initials are produced on the lateral surface of the auxiliary cell opposite the site of connecting filament juncture. In culture, carpospores from field-collected gametophytes developed into crustose plants lacking cell fusions or secondary pit-connections. Irregularly to regularly zonately cleaved tetrasporangia were formed on irregularly branched erect filaments at 24°C, 14:10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h. Monosporangia were also formed terminally on these filaments. At 24°C, 14: 10 h, but not at 16°C, 8: 16 h and 18°C, 16: 8 h, tetraspores from cultured plants germinated to form small, spherical, gelatinous gametophytes which produced carpogonial branches and spermatangia identical to those found on field-collected plants. Spermatia were not seen attached to trichogynes, auxiliary cells did not develop, and no carposporophytes were produced. Monospores probably formed further tetrasporophytes. The species thus appears to have a Bonnernaisonia hamifera-type life history.
The development of the reproductive organs of Sorella repens (Okam.) Hollenberg belonging to the Nitophylloideae of the Delesseriaceae is described. A taxonomical discussion of this plant is also given. The plants were collected at Oshoro Bay, west coast of Hokkaido, Japan. Each of the procarps scattered over the ultimate branches comprises one group of sterile cells and two carpogonial branches arising from a supporting cell. Such a procarp, called Polyneura-type by Kylin, has hitherto been known only in the genus Polyneura among the members of the Nitophylloideae. The manner of the development of the cystocarps belongs to Kylin's Phycodrys-type. The spermatangia develop subterminally from the spermatangial mother cells originating from the pericentral cells. The tetrasporangia arise from both the central and cortical cells.