The great bulk of the world’s charophyte literature of the past 100 years or more suffers from several major limitations. Much is entirely descriptive with but few attempts to ascribe any functionality to the features under consideration, or how they adapt such species to their respective ecological niches. Charophyte distributions have been attributed almost entirely to physical parameters with virtually no consideration given to the role of aquatic herbivores or other biotic environmental factors. Furthermore, most workers have focused on relatively restricted areas with little or no reference to others either near or far removed. That there is much to be gained from a wider focus (both spatially and conceptually) that incorporates greater conjecture as well as enhanced collaboration is here suggested. How are the charophyte floras of one region similar to, or different from, those of another, and, of particular significance, ‘Why?’ The authors, being North American, focus on that continent but with the firm conviction that most generalities applicable there hold equally true for other landmasses, and have done so for the previous 10, if not 100, million years. This account focuses first, if somewhat superficially, on 14 widely distinct North American charophyte communities (plus South American Lake Titicaca) and then in greater detail on four of those. Among other issues considered are how species richness relates to latitude; why some geographical entities support more charophyte species than do others; the extent to which charophyte floras reflect the availability of different habitats; the contributions of herbivory to the preceding; the stability of the North American charophyte flora; the ecological considerations most often reflected by charophyte zonation and how–or to what extent–range extensions reflect niche preferences or requirements. While the authors well appreciate just how minimal their efforts may appear a century hence, at least they hope to have placed on the table some considerations with which colleagues from other landmasses may agree, disagree or suggest modifications.

The rare Newfoundland disjuncts Chara evoluta and Chara canescens are compared morphologically, ecologically, and geographically. Although very similar morphologically, they can readily be distinguished by their monoecious/dioecious nature, cortical cell features and coronula size. Ecological differences are more subtle and difficult to quantify. In Newfoundland the two species are restricted to coastal saline lagoons in the southwest region of the Island, with C. evoluta exhibiting an association with Chara aspera. The flora and fauna of these unique habitats are poorly documented even though it is known that they are associated with other rare species including the Piping Plover and the Banded Killifish. Consideration of some degree of protection as special habitats within the provincial ecological reserve strategy is suggested. An updated key to all species of charophytes known to inhabit Newfoundland and Labrador is included, and a brief overview of their ecological distributions is provided.

Molecular studies have shown the type collection of Omphalina oreades to be conspecific with a small brown basidiolichen from the Appalachian range in Newfoundland, both with 4-spored basidia. Two sequences deposited in GenBank, originally identified as O. grisella, fell in the same clade. Sequences of the type collection of Omphalia grisella, with 2-spored basidia, formed a sister clade together with two GenBank deposits, one identified as O. grisella and the other as Omphalina velutina. Omphalina oreades is recombined here as Lichenomphalia oreades comb. nov., and the species redescribed and illustrated. Sequences of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS rDNA) from the algae associated with two collections of L. oreades fell within a highly supported clade with members of an undetermined species of Coccomyxa. The most abundant algal ribosomal large subunit sequence from granules at the base of a different collection matched GenBank sequences identified as Chloroidium ellipsoideum, which is probably either a free-living algal species or a partner to a species of Trapeliopsis. The second most abundant sequence matched Coccomyxa subellipsoidea and is the most likely photobiont of L. oreades. Further studies are required to elucidate the relationship of L. velutina to these taxa.

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