OCCURRENCE OF PRASIOLA FLUVIATILIS (CHLOROPHYTA) ON ELLESMERE ISLAND IN THE CANADIAN ARCTIC¹

Abstract

Three occurrences of the macroalga Prasiola fluviatilis (Sommerf.) Aresch. were recorded after the examination of 32 stream segments from the Ellesmere Island National Park Reserve (81°23′ N) in the High Arctic of Canada. The collection sites were small (second‐third order) glacial melt streams characterized by pH 7.3–8.2, specific conductance of 52–159 μS·cm−1, low ion levels, extremely low nutrient levels, and the lack of other prominent macroalgae. These occurrences confirm the reported circumpolar distribution of the species.

Microhabitat and morphometric variation in two species of Prasiola (Prasiolales, Chlorophyta) from streams in central Mexico

“…Prasiola mexicana occurred under a wide range of microhabitat conditions, suggesting they tolerate substantial variations of current velocity and irradiance. In this study the current velocity was in the range 0.05-2 m s -1 reported by Hamilton and Edlund (1994) and McClintic et al (2003) for P. fluviatilis, and similar to those for Prasiola sp. in low or zero current velocity (Naw and Hara, 2002).…”

“…Prasiolales green algae have been cited as abundant and frequent components of stream macroalgal communities, and form massive green thalli in temperate, tropical, and boreal climates throughout the world (Starmach 1972;Sheath and Cole 1992;Hamilton and Edlund 1994;Naw and Hara 2002;McClintic et al 2003;Ramírez and Carmona 2005). The genus Prasiola is characterized by a monostromatic laminar thallus and vegetative cells with stellate or lobed chloroplasts containing a single pyrenoid.…”

“…The systematic position of Prasiola has been controversial, because of morphological similarities with marine genera such as Ulva, Monostroma, Enteromorpha, and Rosenvingiella (Smith 1950;Bravo 1965) and overlapping morphometric variation and plasticity within Prasiola (Hamilton and Edlund 1994;Naw and Hara 2002;Rindi et al 1999;Rindi and Guiry 2004). Ramírez and Carmona (2005) analyzed taxonomic characteristics of the two stream species of Prasiola in central Mexico.…”

Biodiversity in extreme aquatic environments: Lakes, ponds and streams of the Ross Sea sector, Antarctica

“…In the Dry Valley streams the species P. calophylla is often found in shaded habitats such as within, between or on the undersurface of rocks (Broady, 1986b). This taxon resembles a species found in similar habitats in high Arctic streams (Hamilton and Edlund, 1994). The fungal biodiversity of the RSS is poorly known in general, but preliminary data are available from a Taylor Valley stream.…”

Environmental factors influencing the pigment composition of in situ benthic microbial communities in east Antarctic lakes

“…Vincent et al 1993, Tang et al 1997, Ellis-Evans et al 1998. Matforming cyanobacteria are generally the major component of these communities (Vincent & Quesada 1994, James et al 1995, while diatoms, green algae and xanthophytes are subdominant (Hamilton & Edlund 1994, Vézina & Vincent 1997. The success of the cyanobacteria is generally attributed to their tolerance to desiccation, freeze-thaw cycles, bright, continuous solar radiation (PAR, Tang et al 1997) and defences against UVR damage (Vincent & Quesada 1994, Ehling-Schulz & Scherer 1999.…”