G. Robin South

Catalogue of the marine benthic macroalgae of the Fiji Islands, South Pacific

A catalogue of the marine benthic macroalgae of Fiji is provided. All records are fully referenced, and type localities and local distributions (accompanied by listings of voucher specimens) are provided. Taxonomic notes are also included where appropriate. Records from SUVA-A, UC and BISH examined by the authors, together with updates from recent publications, form the substance of the report. A total of 448 taxa are included, comprising 136 Chlorophyta, 46 Phaeophyta and 266 Rhodophyta. This represents an increase of 116 new records since 1996, of which 39 are newly reported by the authors, and the remainder are recently published records from the Suva Lagoon (29) and the Great Astrolabe Reef and Lagoon (48). Also included are a total of 36 nomenclatural changes made since 1996, a compilation of 33 uncertain records, and a list of 34 species with type localities in Fiji, Samoa and Tonga. Apart from the far more extensive region of Micronesia, the flora of Fiji is the richest in the south and central Pacific Islands.

Coccomyxa parasitica sp. nov. (Coccomyxaceae, Chlorococcales), a parasite of giant scallops in Newfoundland

Coccomyxa parasitica sp. nov. (Coccomyxaceae; Chlorococcales) is described as a parasite of the marine giant scallop, Placopecten magellanicus Gmelin, from Newfoundland, Canada. Cells occur in colonies distributed through various host organs, but especially in the mantle fold. Cell morphology is highly variable, although characterised by the possession of a distinct hyaline tip which is reduced or absent in culture. Pyrenoids are lacking, 1–3 parietal chloroplasts occur and the cell wall lacks cellulose. Reproduction is by 2, 4 or 8 autospores in the host, and by 2, 4, 8 or 16 autospores in culture. Sexual reproduction is lacking. Pigment analysis reveals the predominance of chlorophyll a, with chlorophyll b, α- and β-carotene and neoxanthin also present. The parasitism is regarded as at best facultative, although free-living C. parasitica is at present not known.

The life history of Turnerella pennyi (Harv.) Schmitz

The life-history and phenology of T. pennyi, regarded as the only species of Turnerella in the north Atlantic Ocean, are described on the basis of culture, cytology and field investigations. In Newfoundland and Labrador, heteromorphic phases occur: tetraspores from an encrusting tetrasporophyte resembling Cruoria arctica/rosea give rise to a similar perennial sterile phase from which the foliose T. pennyi phase arises directly. These foliose plants are dioecious gametophytes. The male gametophyte, reported for the first time, bears spreading spermatangial sori over most of its surface. Old cystocarpic plants may exhibit in situ germination of carpospores. Chromosome counts show that n = 18–20; 2n = 36–40. The indications are that the life-history of the species is similar in other parts of its range, although the longevity of the foliose stage may vary with geographical location and depth. Regeneration of old loose-lying plants readily occurs.

Influence of wave action and latitute on morphology and standing crop of New Zealand Durvillaea antarctica (Chamisso) Hariot (Phaeophyta, Durvilleales)

Abstract Variations in morphology and standing crop of New Zealand Durvillaea antarctica (Chamisso) Hariot are described quantitatively in relation to wave action and latitude. Distinct “thonged” (very strong wave action) and “cape” (moderate wave action) forms are recognised and described. Complete intergradation occurs, but the extent to which a population tends to one form is indicative of the wave forces predominating. Thonged-form plants show increases in overall length, stipe length and diameter, and degree of division and honeycomb development ofthe blade. Cape-form plants show a reduced overall length, stipe length and diameter, and degree of division and honeycombing of the blade. Where the impact force of waves is exceptionally strong plants may become stunted and lack development of a blade base. Generally the species is scarce where wave action is exceptionally strong or where conditions are calm. Regardless of other conditions prevailing the size of stipes increased with latitude. Water turbu...

Observations on phagocytosis of Coccomyxa parasitica (Coccomyxaceae; Chlorococcales) in Placopecten magellanicus

Abstract Phagocytosis of Coccomyxa parasitica in Placopecten magellanicus is described. Host phagocytosis occurs throughout the infective process and can also be demonstrated experimentally using cultured algae. Agranular and granular leukocytes of various types are responsible, and the algae are highly resistant to digestion. The greatest concentration of algae occurs in the scallops mantle region and appears to be related to the circulatory system. The indications are that C. parasitica might enter P. magellanicus via the normal feeding and digestion processes and that host phagocytosis contributes to the spread of the algal cells.

Herpodiscus gen.nov. and Herpodiscus durvilleae (Lindauer) comb.nov., a parasite of Durvillea antarctica (Chamisso) hariot endemic to New Zealand

Abstract Descriptions are given of Herpodiscus gen.nov. (Elachistaceae) and Herpodiscus duroilleae (Lindauer) comb.nov. H. durvilleae is endemic to New Zealand and is restricted to its host Durvillea antarctica (Chamisso) Hariot. The indicatiorrs are that H. duroilleae infection may cause considerable damage to D. antarctica, frequently resulting in the formation of perforations in the blade or, more rarely, complete loss of the blade. The parasite consists of a seasonal phase of assimilators and reproductive filaments, and a perennating internal phase. Reproduction in H. duroilleae is partially described. It includes formation of primary unilocular sporangia, the zoospores of which settle on the adjacent assimilators and give rise directly to secondary unilocular sporangia. The fate of products released from the secondary unilocular sporangia has not been determined, and the infection mechanism is unknown.

Annotated catalogue of the benthic marine algae of the Palolo Deep National Marine Reserve of Samoa

A total of 124 species of benthic marine algae is reported from the Palolo Deep National Marine Reserve on the island of Upolu (Western) Samoa (13°49′S, 171°45′W). Included in the catalogue are 88 Rhodophyceae, 12 Phaeophyceae and 24 Chlorophyceae. This represents the first survey of benthic marine algae for any site in the Samoan Archipelago in the last 76 years. A total of 90 species newly recorded for the region brings the total reported species to 288 (includes Cyanophyceae not reported here). This is about 68% of the current flora from, for example, nearby Fiji. Of the 11 sites investigated, the eastern algal rim of the main Deep (0–10-m depth) is the most diverse, with 68 species. The subtidal (up to 25 m deep) is also diverse with 57 species recorded. The least diverse of all the sites is the Borrow Pit with only six species.

The Global International Waters Assessment for the Pacific Islands: aspects of transboundary, water shortage, and coastal fisheries issues.

Abstract Aspects of transboundary, water shortage, and fisheries issues are discussed in the context of the recently completed Global International Waters Assessment (GIWA) for the Pacific Islands. The region encompasses some 30 million km2 and approximately 12% of the worlds ocean space, and features great geographic, demographic and developmental diversity. Global change, especially sea level rise and sea surface temperature increases, is the dominant transboundary concern as it impacts all aspects of life. Water shortage and unsustainable fishing issues are selected for discussion, as they will dominate the region into the foreseeable future, and they are illustrated with examples from Fiji, Kiribati, and Tonga. The environmental impacts are exacerbated by socioeconomic issues such as high population growth rates, urban drift, the breakdown of traditional life styles and the rapid adoption of the cash economy. Policy options that may assist in addressing these issues are proposed.

Aspects of the reproductive phenology of Saccorhiza dermatodea (Phaeophyta, Laminariales) in Newfoundland

The phenology of Saccorhiza dermatodea is described from the island of Newfoundland, Canada, and the possible roles of daylength and temperature in controlling the annual cycle are examined. New sporophytes first appear in late March or early April and continue to appear until late May or early June; there is, however, considerable year-to-year and local variation in the timing of the first appearance of the new sporelings. The reproductive maturation of the sporophytes is rapid, commencing at the end of September. Within 2 weeks of the first appearance of sorus tissue, 100% of the population is fertile. Fertile sporophytes may persist until July of the following year. Viable zoospores were obtained from the beginning of the fertile period until April of the following year. The annual cycle is correlated with seasonal temperature and daylength fluctuations. The new generation of sporophytes appears when water temperature is at its winter low, nutrients are maximal and daylength and light intensity are inc...

Olpidiopsis antithamnionis n. sp. (Oomycetes, Olpidiopsidaceae), a parasite of Antithamnion floccosum (O. F. Müll.) Kleen from Newfoundland

SummaryOlpidiopsis antithamnionis n. sp. (Oomycetes, Olpidiopsidaceae) parasitic on Antithamnion floccosum (O. F. Müll.) Kleen (Rhodophyta, Ceramiaceae) is described from three sites in Newfoundland, Canada, and from culture.Axial cells of the main and determinate branches of the host are the primary sites of fungal attack, although tetrasporangia and rhizoidal cells are also susceptible. Successful re-infection of A. floccosum was achieved in the laboratory although A. boreale and the trailliella-phase of Bonnemaisonia hamifera, both occurring with A. floccosum in the field, were immune. Regeneration of the host cells was observed, a phenomenon not previously reported in the fungal parasitism of other filamentous benthic marine algae.