DISTRIBUTION AND SYSTEMATICS OF BATRACHOSPERMUM(BATRACHOSPERMALES,RHODOPHYTA) IN NORTH AMERICA. 6. SECTION TURFOSA1

Twenty-one populations of Batrachospermum section Turfosa from North America were compared to nine type and two historically important specimens using multivariate morphometrics and image analysis. The protologues of six other infrageneric taxa were also compared. From this analysis, six species are recognized worldwide: B, de-sikacharyi Sankaran, B. gombakense Kumano et Ratnasabapathy, B. keratophytum Bory de Saint-Vincent [syn. B. vagum var. keratophytum (Bory de Saint-Vincent) Sirodot, B. gulbenkianum Reis, and B. suevorum Kützing nom. Meg.], B. sinense Jao, B. turfosum Bory de Saint-Vincent [syn. B. vagum (Roth) C. Agardh and B. vagum var. undulato-pedicellatum Kumano et Watanabe], and B. vogesiacum F. G. Schultz ex Skuja [syn. B. vagum var. flagelliforme Sirodot, B. flagelliforme (Sirodot) Necchi], These species are distinguished on the basis of carposporophyte-bearing branch cortication, secondary fascicle development, monoecy or dioecy, presence of spermatangia on involucral filaments and monosporangia, and dimensions of trichogynes and carposporangia. Peripheral cortication has been previously used to separate species in this section, but we observed that this feature is quite widespread in the section. Presence of indeterminate gonimoblast filaments has been reported for some taxa in section Turfosa, but no such structures were seen in any of the specimens examined. Only B. keratophytum has been collected in North America, ranging from southwestern Greenland (64°N) to Louisiana (30° N).     

BIOGEOGRAPHY AND TAXONOMY OF BATRACHOSPERMUM HELMINTHOSUM (BATRACHOSPERMALES,RHODOPHYTA) IN JAPAN INFERRED FROM RBCL GENE SEQUENCES1

Twenty‐seven individuals of Batrachospermum helminthosum Bory were collected from various sites in Japan, from temperate Iwate Prefecture to subtropical Okinawa Prefecture. The chloroplast‐encoded rbcL gene was sequenced from each sample. Phylogenetic analyses were performed using these and previously published sequences of 12 samples from North America. There were five haplotypes among the Japanese samples. Haplotype 1 was collected throughout a large geographical area corresponding to most of the sampling range in this study and was represented by most individuals (21 individuals). The other haplotypes were represented by one to three individuals, respectively. These distributions of haplotypes suggest the occurrence of one large metapopulation and/or recent colonization over a wide geographical area in Japan. Phylogenetic analysis showed two well‐supported clades within B. helminthosum, one clade containing four haplotypes (1–4) from Japan and the other clade comprising five North American haplotypes. Such differences between Japanese and North American haplotypes might be a result of continental drift and subsequent isolation in the Mesozoic era. The position of haplotype 5 from Okinawa in Japan is poorly resolved, but it is not closely related to the other four Japanese haplotypes. It is suggested that several taxonomic characteristics (sexuality, point of origin of carpogonium‐bearing branches, and trichogynes with or without basal knobs or branching) is not fixed genetically but is affected by environmental conditions. Based on the results of the present study, B. coerulescens Sirodot and B. elegans Sirodot should be placed in synonymy with B. helminthosum.     

Ultrastructure of carpogonia and carpogonial branches of Batrachospermum helminthosum and Batrachospermum involution (Batrachospermales, Rhodophyta)

The carpogonial branches of Batrachospermum involutum of section Batrachospermum are similar in ultrastructure to nearby fascicles, having uninucleate cells with abundant starch granules and several peripheral, well-developed chloropiasts (up to 10 μm long). In contrast, the short carpogonial branch cells of Batrachospermum helminthosum (section Virescentia) have no visible starch and chloropiasts are reduced in size (up to 2 μm long) with few thylakoids. The breakdown of cross walls among cells of the carpogonial branch is also common in B. helminthosum but does not occur in B. involutum. As a result of cross wall breakdown in the former species, 2-7 nuclei can occur in a continuous cytoplasm. Trichogynes in both species contain scattered mitochondria, vesicles/small vacuoles, osmiophilic globules, endoplasmic reticulum (ER) and small chloropiasts. Polylamellate structures also occur in the trichogyne in B. involution. The carpogonial base was fully observed only in B. involutum and it contains a prominent nucleus, ER, chloropiasts and a pit plug connecting it to the subtending carpogonial branch cell. Partial observations of carpogonial branches and carpogonia were made on four other members of the family Batrachospermaceae.     

MORPHOMETRY OF BATRACHOSPERMUM POPULATIONS INTERMEDIATE BETWEEN B. BORYANUM AND B. ECTOCARPUM (RHODOPHYTA)1

Batrachospermum plants collected as part of a comprehensive study of New England streams were found to be intermediate between B. boryanum Sirdt. find B. ectocarpum Sirdt. Sixty-four specimens from ten Rhode Island streams were examined for several characteristics in replicates of two to four hundred. The size ranges obtained were then compared with previous published data for B. boryanum and B. ectocarpum from Europe, Asia and North America. The Rhode Inland populations and individuals exhibited as much or even more variability as that reported for both species combined throughout the world. Therefore, it appears that there is no definite basis for separation of these taxa and it is proposed that they be merged under the name B. boryanum. This combined species ran be distinguished from other species of the section Batrachospermum by compressed mature lateral whorls, little secondary fascicle formation, curved distal branching, terminal hairs on a small proportion of branches, predominantly dioecious state, sessile trichogynes and carposporophytes in outer portions of lateral whorls.     

Contrasting intra versus interspecies DNA sequence variation for representatives of the Batrachospermales (Rhodophyta): Insights from a DNA barcoding approach

Sixty‐five accessions of the species‐rich freshwater red algal order Batrachospermales were characterized through DNA sequencing of two regions: the mitochondrial cox1 gene (664 bp), which is proposed as the DNA barcode for red algae, and the UPA (universal plastid amplicon) marker (370 bp), which has been recently identified as a universally amplifying region of the plastid genome. upgma phenograms of both markers were consistent in their species‐level relationships, although levels of sequence divergence were very different. Intraspecific variation of morphologically identified accessions for the cox1 gene ranged from 0 to 67 bp (divergences were highest for the two taxa with the greatest number of accessions; Batrachospermum helminthosum and Batrachospermum macrosporum); while in contrast, the more conserved universal plastid amplicon exhibited much lower intraspecific variation (generally 0–3 bp). Comparisons to previously published mitochondrial cox2–3 spacer sequences for B. helminthosum indicated that the cox1 gene and cox2–3 spacer were characterized by similar levels of sequence divergence, and phylogeographic patterns based on these two markers were consistent. The two taxa represented by the largest numbers of specimens (B. helminthosum and B. macrosporum) have cox1 intraspecific divergence values that are substantially higher than previously reported, but no morphological differences can be discerned at this time among the intraspecific groups revealed in the analyses. DNA barcode data, which are based on a short fragment of an organellar genome, need to be interpreted in conjunction with other taxonomic characters, and additional batrachospermalean taxa need to be analyzed in detail to be able to draw generalities regarding intraspecific variation in this order. Nevertheless, these analyses reveal a number of batrachospermalean taxa worthy of more detailed DNA barcode study, and it is predicted that such research will have a substantial effect on the taxonomy of species within the Batrachospermales in the future.     

A NEW MODE OF LIFE HISTORY IN THE FRESHWATER RED ALGAL GENUS BATRACHOSPERMUM

In a new type of Batrachospermum life history, the Batrachospermum phase does not originate from the erect filaments of a Pseudochantransia but directly from a prostrate crustose growth, the prothalle of Sirodot. It is probable that the few lowermost segments of those Batrachospermum cladomes are diploid, the remainder due to an interposed “somatic” meiosis are haploid.     

The marine algae of the Hebridean Island of Colonsay

Four specimens attributable to the freshwater red algal taxon, Ptilothamnion richardsii, were examined from locations in Australia and French Guiana, and partial rbcL gene sequence data were obtained. Phylogenetic analyses showed these specimens to be allied to taxa in the Batrachospermales. The two specimens from Australia were determined to be Batrachospermum antipodites, differing from that taxon by only 15?bp (1.2%). The two specimens from French Guiana were within the Batrachospermum section Contorta clade, but differed considerably (≥8%) from the taxa for which there are presently rbcL gene data. The sequence data clearly show these specimens to be chantransia stages of Batrachospermum taxa. Recently, other described freshwater Audouinella taxa have also been shown to be chantransia stages. Like previous authors, we argue that it is useful to continue to recognize entities with particular morphological characters and propose the form taxa Chantransia richardsii, C. macrospora and C. pygmaea. A key to these is provided.     

Insights into the Witheringia solanacea (Solanaceae) Complex in Costa Rica. II. Insect Visitors and Pollination Biology of W. asterotricha and W. meiantha1

Isolating mechanisms are important in maintaining the taxonomic integrity of closely related sympatric taxa. A previous study found strong post‐zygotic isolating barriers between two species, Witheringia asterotricha and W. meiantha, of the W. solanacea (Solanaceae) species complex in Costa Rica. This study examines the presence of pre‐zygotic barriers between the two species at La Selva Biological Station in Costa Rica. Both species offer pollen and nectar as floral rewards and are visited primarily by solitary or semi‐social bees, some of which sonicate (“buzz”) the anthers to discharge pollen. No evidence was found for phenological differences in flowering time between W. asterotricha and W meiantha, but pre‐zygotic factors, such as ethological isolation and possibly fine‐scale ecological or geographic barriers, may be responsible for restricting gene flow between the two species.     

BATRACHOSPERMUM HETEROCORTICUM SP. NOV. AND POLYSIPHONIA SUBTILISSIMA (RHODOPHYTA) FROM FLORIDA SPRING-FED STREAMS1

Polysiphonia subtilissima Mont. Is reported for the first time from a freshwater environment. The presence of four pericentral cells, subdichotomous branching, apical trichoblasts and rhizoids arising from pericentral cells combined with a lack of cortication and reproductive cells is consistent with marine populations of this species. The range of filament length is 1.4–4.7 cm. Branch diameters are 38–76 μm and pericentral cell lengths are 58–125 μm. Batrachospermum heterocorticum sp. nov. is distinguished primarily by a developmental change in cortical filaments from typical cylindrical cells (5.0–7.9 μm diam in initial stages to enlarged, elliptical cells (12.9–24.1 μm diam) in mature axes. Another unique feature of this species is carpogonia with cylindrical, pedicellate trichogynes on stringht carpogonial branches in mid to outer portions of lateral whorls. Other characteristics of B. heterocorticum include the following: olive-green color, 2–6 cm length, dichotomous to trichotomous fascicles in 4–7 tiers, 385–647 μm whorl diameters, 109–198 μm carpospore diameters and relatively small “chantransia” filaments.     

A new eutardigrade from Costa Rica with taxonomical and zoogeographical remarks on Costa Rican tardigrades

In a moss sample collected in Costa Rica, 63 specimens and 13 eggs of the new species were found. Mesobiotus pseudopatiens sp. nov. belongs to the harmsworthi group and is most similar to Mesobiotus patiens, but it differs from it mainly by smaller eggs, longer flexible portions of egg processes and certain morphometric characters of adults. In addition, after re-examination of specimens of the genus Milnesium collected in Costa Rica, a new record of Milnesium kogui may be added to Costa Rican fauna. The paper also discusses taxonomical problems and the zoogeography of Costa Rican tardigrades, which partially agree with hypotheses of Great American Biotic Interchange and Mexican Transition Zone. A large number of so-called ‘Costa Rican species’ are doubtful taxa with ‘cosmopolitan’ distribution; the largest number of species, however, have tropical/subtropical or neotropical distribution. Certain species from colder regions are also present in the mountains of Costa Rica.

http://zoobank.org/urn:lsid:zoobank.org:pub:F6F6195E-0888-4279-A3AF-422642F8B40     

Phenology and phylogenetic positioning of the Hawaiian endemic freshwater alga, Batrachospermum spermatiophorum (Rhodophyta, Batrachospermales)

The only known population of Batrachospermum spermatiophorum Vis et Sheath, located in a small stream on east Maui, Hawaii, was sampled from November 2001 to October 2002 to investigate its phenology. Additionally, the taxonomic status of the alga was examined. Phylogenetic analyses of the large subunit of the ribulose‐1,5‐bisphosphate carboxylase/oxygenase (rbcL) gene for B. spermatiophorum confirm its placement within the Section Contorta of the genus Batrachospermum. Comparisons with rbcL gene sequences for all other available Batrachospermum species, including 10 other members of the Section Contorta, illustrate that B. spermatiophorum is distinct in its rbcL nucleotide sequence and should be maintained as a separate species. The phenology of B. spermatiophorum differed from most studies of Batrachospermum reproduction in that the gametophytes were present year round, and no macroscopic chantran‐sia stages were identified at any point during the present study. Maximum plant length was highest in the late fall and early winter months, while gametangial production peaked in February and March. Carposporophyte abundance rose sharply in July and August, and the percentage of carposporophytes producing carpospores was highest in late summer and early fall months. Although significant correlations were determined among stream conditions and among phenological characteristics, only pH was associated with several of the reproductive characters, which is unusual for studies of Batrachospermum phenology. Timing of sexual reproduction for all macroalgal community members in the stream site was not coordinated, with some reproducing year round and others more sporadically. The year‐round presence of Batrachospermum gametophytes may be a result of a combination of smaller seasonal changes in cues such as day length and water temperature in the tropical environment than occur in temperate locations, and lack of extreme conditions that might inhibit the persistence of the gametophyte.     

Two new species of Blechnum (Blechnaceae) from the neotropics

Blechnum moranianum is a new species similar toB. loxense, andB. nigrum is segregated from theB. fragile complex. Both are described and illustrated as result of the author's taxonomic fern work in Costa Rica. Blechnum moranianum es una especie nueva similar aB. loxense, yB. nigrum es segregada del complejoB. fragile. Ambas son aquí descritas e ilustradas como resultado de los trabajos taxonómicos del autor en los helechos de Costa Rica.     

Distribution of diploid sexual plants ofTaraxacum sect.Ruderalia in east-Central Europe,with special reference to Czechoslovakia

Herbarium specimens (c. 1 000) and population samples (76) have been screened for the occurrence of diploid representatives ofTaraxacum sect.Ruderalia (T. sect.Vulgaria, nom. illeg.). The area studied comprises German Democratic Republic, Poland, Czechoslovakia, Hungary and parts of Austria, Yugoslavia, and Rumania. Diploids are common from the Valley of the Moravia river on southwards. Isolated outpost localities are found in S. Poland and extend far to the north: neighbourhood of Berlin. Based on the pattern of distribution in Czechoslovakia, the Pannonian (thermophilous) phytogeographical character of the diploids is discussed. Special attention has been paid to morphological differences between di- and triploids in Czechoslovakia. The study provides a basis for further biosystematical and taxonomic studies in the relationships between diploids and polyploids as well as in the stability of agamospecies.     

DISTRIBUTION AND SYSTEMATICS OF FRESHWATER CERAMIALES (RHODOPHYTA) IN NORTH AMERICA1

Twenty-five freshwater populations of Ceramiales were collected in North America, 24 of which were from the tropical rainforest region of Central America and the Caribbean. The streams tended to be moderate in mean current velocity (X?= 23.3 cm·S^?1) and maximum width (X?= 6.3 m) but high in temperature (X?= 23.1°C), pH (X?= 7.9), and specific conductance (X?= 320 μS·cm^?1). Three Bostrychia species were restricted to the Caribbean islands: B. moritziana (Sonder ex Kütz.) J. Ag. (syn. B. cornigera Mont. and B. radicans f. moliforme Post), with ecorticate indeterminate axes, monosiphonous ultimate branches, and cladohaptera; B. radicans (Mont.) Mont. (syn. B. leprieurii Mont and B. rivularis Harv.), with ecorticate and polysiphonous axes throughout and cladophaptera; and B. tenella (Lamour.) J. Ag., with corticate indeterminate axes, monosiphonous ultimate branches, and peripherohaptera. Ballia prieurii Kütz. was found in Belize and Costa Rica and was characterized by rebranched determinate laterals, opposite branching, and long apical cells (X?= 61 μm) and axial cells (X?= 43 μm). Caloglossa leprieurii (Mont.) J. Ag. was localized in Puerto Rico while. C. ogasawaerensis Okam. was collected only in Costa Rica. The two species were separated by site of branching (midrib vs. margin) and blade width (X?= 384 vs. 861 μm). Polysiphonia subtilissima Mont. from Florida and Jamaica had four pericentral cells, no cortication, rhizoids arising from pericentral cells, and branches initiated at trichoblast scars.     

Typification and status of Amphiroa cryptarthrodia Zanardini (Lithophylloideae,Corallinales, Rhodophyta)

The status of the name Amphiroa cryptarthrodia Zanardini has been uncertain, and there has been a lack of stability in this species nomenclature, in part related to its poor taxonomic foundation. The species has been considered conspecific with Amphiroa verrucosa Kützing nom. illeg. Another suggested taxonomic synonym has been Amphiroa rubra (Philippi) Woelkering. A type specimen for A. cryptarthrodia appears never to have been designated and there are no illustrations of Zanardini's original collections housed in the Museo Civico di Storia Naturale, Venezia (MCVE). In the present paper, a neotype of A. cryptarthrodia is designated, based on the study of Zanardini's authentic collections. A detailed morphological and anatomical account of the type specimen is provided and the diagnostic characters of the species are listed. Nomenclatural and taxonomic data and brief considerations of the relationships between A. cryptarthrodia and conspecific species are also provided. It is concluded that A. verrucosa Kützing is a heterotypic synonym. The name A. rubra (Philippi) Woelkerling should remain, pertaining solely to its type pending new investigations.     

Distribution and synonymy of Plagiochila punctata (Taylor) Taylor, with hypotheses on the evolutionary history of Plagiochila sect. Arrectae (Plagiochilaceae, Hepaticae)

For a long time, Plagiochila (sect. Arrectae) punctata (Taylor) Taylor has been treated as an endemic of Atlantic Europe. Studies of larger specimen sets demonstrated that the species is widespread in mountainous regions of the Neotropics where it is known under several names including P. stolonifera Lindenb. & Gottsche, P. choachina Gottsche and P. patzschkei Steph. In tropical Africa P. punctata is established as Plagiochila subalpina Steph., nom. illeg. The sporophyte of P. punctata is described for the first time, based on material from Costa Rica. A maximum likelihood analysis of a nrITS sequence alignment with sequences of P. sects. Fuscoluteae (outgroup), Arrectae, and Rutilantes as well as of P. rubescens (Lehm. & Lindenb.) Lindenb. results in a tree with well bootstrap supported Arrectae and Rutilantes clades. ITS sequences of Plagiochila punctata from the Comoros and Zaire are placed in an unsupported monophyletic lineage together with P. punctata sequences from the British Isles and Ecuador. The species is nested in a robust clade with P. spinulosa (Dicks.) Dumort. and P. stricta Lindenb. The weak genetic separation of these three species indicates a recent diversification; the disjunct ranges may be the result of long range dispersal events. Plagiochila rubescens from southern South America is placed sister to P. sect. Arrectae. The latter section possibly originated from southern South American ancestors, diversified in tropical America after the uplift of the Andes and reached the Holarctics and tropical Africa by long range dispersal of diaspores.We are grateful to the curators and owners of the herbaria cited in the text for the loan of specimens, especially to Tamás Pócs, Volker Buchbender and Eberhard Fischer for their continuous support with recent collections from tropical Africa. David Rycroft kindly sent a duplicate of P. rubescens. Financial support of the Deutsche Forschungsgemeinschaft (grant HE 3584/1) is gratefully acknowledged.     

中国串珠藻属新记录

记述了我国串珠藻属的6个新记录种,即灌丛串珠藻(Batrachospermum lochmodes Skuja),内卷串珠藻(B. involutum Vis et Sheath),博雷串珠藻(B. boryanum Sirodot),下位串珠藻(B. hypogynum Kumano et Ratnasabapathy),阿比串珠藻(B. abilii Reis)和茶溪串珠藻(B. theaquum Skuja ex Entwisle et Foard)