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Chironomid larvae incorporate pieces of freshwater red algae into their cases from a wide geographic range in North America, extending from southern Canada to central Mexico. The Rhodophyta used in this process represent two orders (Acrochaetiales and Batrachospermales), five genera (Audouinella, Batrachospermum, Lemanea, Paralamanea, and Sirodotia), and 14 species from 21 locations. Three genera from the chironomoid subfamily Orthocladiinae make these cases: Cardiocladius, Eukiefferiella, and Orthocladius. The Eukiefferiella claripennis group was the most frequently observed infrageneric taxon using red algae in its cases. The cases were tubular in shape with longitudinally oriented strips of algae held together by silken threads. Some of the cases constructed with Batrachospermum and Sirodotia also had several lateral branches of the alga radiating from their tube. [ABSTRACT FROM AUTHOR]

Cases of larvae and pupae from six caddisfly (Insecta, Trichoptera) genera in three families from North America were observed to contain pieces of freshwater rhodophyte thalli. Seven genera of Phodophyta, representing 13 species and 35 populations, were observed in this association. Four of the 25 species of Batrachospermum were incorporated into cases of Ochrotrichia (Hydroptilidae) and Agrypnia (Phryganeidae). Two of the three freshwater species of Bostrychia were used by Ochrotrichia larvae. Both Compsopogon coeruleus (Balbis) Mont. and C. prolificus Yadava et Kumano were present in the cases of Hydroptila (Hydroptilidae) and Ochrotrichia; Compsopogonopsis leptocladus (Mont.) Krishnamurthy was observed in the cases of Hydroptile. The more cartilaginous thalli of Lemanea fluviatilis (L.) C. Ag. And Tuomeya Americana (Kütz.) Papenfuss were used by the brachycentrid larvae of Brachycentrus and Micrasema. Lemanea and Paralemanea spp. were also in the cases of Dibusa angata Ross (Hydroptilidae). The architecture of each caddisfly case was studied with light and scanning electron microscopy. Strips of algae were fu together in a transverse, concentric, or spiralled fashion. Based on transmission electron micrographs, cortical cells of Lemanea and Tuomeya in the cases of Brachycentrus and Micrasema appeared to be healthy with intact chloroplasts and typical batrachospermalean pit plugs. Geographic distributions of each rhodophyte-caddisfly association are given. [ABSTRACT FROM AUTHOR]

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. desikacharyi 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. illeg.], 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 not such structures were seen in any of the specimen examined. Only B. keratophytum has been collected in North America, ranging from southwestern Greenland (64° N) to Louisiana (30° N). [ABSTRACT FROM AUTHOR]

Thirty-nine populations of Batrachospermum section Virescentia from North America were compared to eight Ope specimens and two historically important specimens using multivariate morphometrics and image analysis. From this analysis, two species ore recognized: B. heiminthosum Bory de Saint-Vincent (syn. B. bruziense Sirodot, B. graibussoniense Sirodot, B. sirodotii Skuja ex Flint, B. testale Sirodot, B. virgatum Sirodot nom. illeg., and B. viride Sirodot) and B. elegans Sirodot (syn. B. coerulescens Sirodot nom. illeg.). In B. helminthosum trichogynes are cylindrical to slightly club-shaped with few to no protuberances, whereas in B. elegans half to all of the trichogynes have one to three basal knobs or branches. None of the qualitative features previously used to separate species in this section were found to be of taxonomic value due to their universal presence; quantitative characteristics were highly variable and overlapped among specimens examined. Emended descriptions of both species are provided. Batrachospermum elegans was collected in northeastern US.A. and central Costa Rica, whereas B. helminthosum ranged from Nova Scotia to Louisiana and was collected in central Mexico, Costa Rica, and northwestern U.S.A. Batrachospermum julianum Arcangeli and B. transtaganum Reis, previously classified in section Virescentia, were observed to have twisted carpogonial branches and, therefore, should be placed in section Contorta. Sections Setacea and Virescentia of Batrachospermum differ in whorl size, ratio of carposporophyte height to whorl diameter, and trichogyne stalking, hence, we continue to recognize them as being distinct taxonomic entities as originally described. [ABSTRACT FROM AUTHOR]

Six populations of Batrachospermum section Setacea from North America were compared to eight type specimens using multivariate morphometrics and image analysis. From this analysis, four species in this section were distinguished worldwide: B. attrum (Hudson) Harvey [syn.B. gallaei Sirodol, B. orthostichum Skuja, B. sertularina (Bory) Bory]; B. diatyches Entwisle; B. androinvolucrum sp. nov.; and B. puiggarianum Grunow in Wittrock et Nordstedt (syn. B. angolense Welwitsch ex West et West, B. nigrescenes Welwitsch ex West et West). Two of these species were found in North America: B. attrum in California and Texas and B. androinvolucrum in British Columbia, Washington State, and Alabama. The new species, B. androinvolucrum, is distinguished by having spermatangia restricted to one-celled involucral bracts of the corpogonial branch [ABSTRACT FROM AUTHOR]

Multivariate morphometrics and image analysis were used to determine the number of well-delineated infrageneric taxa 0fSirodotia in North America. Three groupings were distinguished from 25 populations examined from Newfoundland and Quebec in the north to central Mexico in the south. These groupings were statistically related to 10 type specimens, and the following species were recognized: Sirodotia huillensis (Welwitsch ex W. et G. 3. West) Skuja (syn. S. ateleia Skuja), S. suecica Kylin (syn. S. acuminata Skuja ex Flint and S. fennica Skuja), and S. tenuilssima (Collins) Skuja ex Flint. These speies are differentiated on the basis of whorl shape and appressed; S. huillensis and S. tenuissima, truncated apex and separated), the density of spermatangia (S. huillensis, dense clusters; S. suecica and S. tenuissima, sparsely aggregated), and the mode of germination of the gonimoblast initial (S. suecica and S. tenuissima, from the nonprotuberant side of the fertilized carpogonium; S. huillensis from the protuberant side). Sirodotia huillensis was found only in the desert-chaparral, whereas S. succica and S. tenuissima occurred from southtemperate to boreal regions in cool (temperature 8-18°C), low ion (specific conductance 10-99 μ°cm[SUP-1], and mildly acidic to neutral (pH 5.7-7.3) waters. [ABSTRACT FROM AUTHOR]

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 (&Xbar; = 23.3 cm·s[sup-1]) and maximum width (X = 6.3 m) but high in temperature (&Xbar;= 23.1°C), pH (&Xbar; 7.9), and specific conductance (&Xbar; = 320 μS·cm[sup-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. moniliforme 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 cladohaptera; and B. tenella (Lamour.) J. Ag. with core, cate indeterminate axes, monosiphonous ultimate branches, and peripherohaptera. Ballia prieurii Kütz. was found in Belize and Costa Rica and u, as characterized by rebranched determinate laterals, opposite branching, and long apical cells (&Xbar; = 61 μm) and axial cells (X 43 μm) Caloglossa leprieurri (Mont.) J. Ag. was localiud 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 384 us 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. [ABSTRACT FROM AUTHOR]

Studies the distribution and systematics of the freshwater genus Tuomeya fluviatilis. Gametophyte development from a basal mass of undifferentiated cells rather than a chantrasia stage; No morphometric, environmental or geographic basis for separation of the groupings found.

In a survey of 1000 20-m long stream segments in North America from 73° N to 10° N, 259 infrageneric taxa were identified, composed of 35% Chlorophyta, 24% Cyanophyta, 21% Chrysophyta, 20% Rhodophyta, and one species of Phaeophyta. The most common morphological forms were mats (42%), gelatinous colonies (23%), and gelatinous filaments (13%); the majority of taxa were vegetative (78%). The frequency of reproductive states varied among the biomes examined, with the highest values observed as follows: vegetative (85%) in the tundra, sexual (35%) in the deciduous forest, and asexual (21%) in the tropical rainforest. In terms of total species, the tundra had the lowest number (54), the boreal forest had the greatest number (100), and other well-sampled biomes had 84 to 87. The Chlorophyta had the greatest species numbers in all biomes, and the relative contribution of this division did not vary significantly throughout the continent. With regard to similarity of species composition, the two closest associations were the boreal forest with the western coniferous forest and the eastern hemlock-hardwood forest with the deciduous forest. Species numbers per stream segment ranged from 0 to 11 (&Xsline; = 3.1), cover ranged from 0 to 100% (&Xsline; = 15%), and there was no significant difference in these values among the biomes. The cyanophyte Phormedium retzii (C. Ag.) Gom. was the most widespread species (in 172 segments and all biomes). The majority of species were found in moderate current velocities (&Xsline; = 40 cm · s[SUP-1]), neutral to slightly alkaline pH (&Xsline; = 7.5), and moderately low ion waters (&Xsline; = 261 μS · cm[SUP-1]). On both tropical and Arctic islands, there was no significant increase in total species or species numbers per stream segment with increasing surface area. [ABSTRACT FROM AUTHOR]

Multivariate morphometrics and image analysis were used to determient he number of well-distinguished infrageneric taxa in the section Contorta of the freshwater red algal genus Batrachospermum in North America. Five groupings were distinguished from 29 populations examined from New Mexico to costa Rica. These entities were statistically related to 12 type specimens reported from or similar to North American populations. The following taxa were recognized: B. ambiguum Montagne (syn. B. bicudoi Necchi and B. basilare Fling et Skuja) B. globosporum Israelson (syn. B. cipoense Kumano et Necchi and B. Jolyi Necchi), B. intortum Jao, B. louisianae Skuja and B. Procarpum Skuja var. americanum var. nov. The new variety differs from the nominate variety in having significantly larger whorls and smaller carpogonia. Batrachospermum ambiguum, B. louisianae, and B. procarpum var. americanum occur in low ion waters (10-187 μS·cm[SUP-1]), whereas B. intortum and B. globosporum are found in h igh ion waters (260-1760 μS·cm[SUP-1]). Detailed descriptions and a key to the five taxa are given. [ABSTRACT FROM AUTHOR]

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 straight 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. [ABSTRACT FROM AUTHOR]

Cellulose acetate of the hot water soluble polysaccharide extracts from whole filaments, as well as base., mid and tip segments, of marine asexual and sexual Bangia atropurpurea (Roth) C. Ag. yielded distinctive patterns which demonstrated that changes occur in the outer cell walls during sexual reproduction. Heterogeneity of the sulfated polysaccharide components isolated from outer cell walls was shown to be specifically related to sexual reproduction. Two components (Bands I and II) were detected in extracts from tips of sexual filaments, while only one (Band I) was present in the vegetative segments of all filaments and in asexual reproductive regions. The faster running component (Band II) was detected during the later stages of sexual development, prior to maturation. [ABSTRACT FROM AUTHOR]

Presents comparative studies on the cell walls of sexual and asexual Bangia atropurpurea. Histochemical study of the nature and distribution of acidic and neutral cell wall polysaccharides; Detection of neutral polysaccharides in the outer coating; Presence of acidic polysaccharides in the outer wall material; Change in the nature of the acidic component during sexual reproduction.

Focuses on the distribution, seasonality and reproductive phenology of Bangia atropurpurea in Rhode Island. Bangia populations in winter; Upper intertidal populations from September to May; Maximum diameter of asexual and carpogonial filaments; Correlation of monosporogenesis to temperature; Relationship of gametogenesis to photoperiod.

The fine structure of released, attached, and germinating carpospores of Porphyra variegata (Kjellm.) Hus is described. Adhesive vesicles, formed during sporogenesis and discharged upon settling of the spore, produced a layer of adhesive mucilage around the spore and filled a deep invagination on the spores ventral side. The mucilage layer was punctured by the emergence of a germ tube. Both spore and germ tube were lined by newly deposited cell wall. Germination was accompanied by vacuolation and starch mobilization. The morphological development of the sporeling was not noticeably influenced by the great variability of the timing, location, and orientation of septum formation. The attached carpospore possessed a plastid like that of gamatophyte cells: stellate with one large central pyrenoid and no peripheral encircling thylakoids. Cells of mature vegetative cells of the conchocelis had plastids that were elongate and parietal and had multiple pyrenoids and encircling thylakoids. Most stages in the transition between the two forms of plastids occurred during carpospore germination. [ABSTRACT FROM AUTHOR]

Chromosome number and morphology as well as reproductive seasonality were examined in Bangia populations collected from 88 sites along the British Columbia coasts. Sexual filaments were recorded at 35 sites and asexual filaments at 58. Four different types of Bangia were determined. These were characterized by reproductive state and chromosome number, as well as by their seasonality and range of distribution. A summer-fall three-chromosome sexual type occurred from approximately 50° N northward and a winter-spring four-chromosome sexual type had a northerly limit of approximately 54°N. extending to the southernmost areas of British Columbia. Two asexual types occurred, exhibiting little seasonality, six-chromosome populations at three southerly sites only. Karyograms were prepared for the four chromosomal types, assigning tentative centromere locations. Somatic chromosome pairing was reported for the first time in the Rhodophyta. [ABSTRACT FROM AUTHOR]

Discusses the ultrastructure of sperm from species in genera of Laminariales collected in the northeast Pacific Ocean. Uniqueness of the features in the brown algae; Presence of mitochondria and chloroplasts in the sperm; Support of the concept that Chorda is the most primitive member of the Laminariales.

Reports on a study by electron microscopy of zoospores of Laminariales collected in the northeast Pacific Ocean. Uniqueness of the zoospores in the brown algae; Presence of a distal whiplash portion on the mastigoneme-bearing anterior flagellum; Role of the microtubular cytoskeleton in maintaining the shape of the spore; Variation of the taxonomic significance in the ultrastructure of the vesicles.

In a survey of the distribution of Bangia atropurpurea (Roth) Ag. Along the north and east shorelines of the Laurentian Great Lakes, it was observed that this species was concentrated in the lower lakes. Asexual reproduction by monospore formation was the only form of reproduction in these populations. First generation germlings derived from these spores grew in a wide range of salinities from 1 to 26%, but the rate was inversely proportional to salinity. In addition, acclimation of parent plants to fresh-water or marine media prior to sporulation affected growth rates of first generation germlings placed into a series of salinities. By the second and third generation, germlings with a lineage of seawater showed a preference for the higher salinities, 19 and 26%. Plants collected in Lake Ontario exhibited no decline in photosynthetic rate as salinity was raised by 13% for 15 min. At 26% the rate was reduced by half and thylakoids were disrupted in the region of the pyreniod. On the other hand, third generation plants with a history of seawater attained maximum photosynthetic rates at 26% and contained a normal thylakoid organization. Three chromosomes were observed in these plants, which agrees with some of the previous findings for marine Bangia. Origins and taxonomic status of Bangia growing in the Great Lakes are discussed in light of these findings. [ABSTRACT FROM AUTHOR]