''Ulvaria obscura'' is an

intertidal The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

and

subtidal The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated ...

benthic

marine algae Marine primary production is the chemical synthesis in the ocean of organic compounds from atmospheric or dissolved carbon dioxide. It principally occurs through the process of photosynthesis, which uses light as its source of energy, but it al ...

found in temperate and Arctic ocean waters around the world.

Ecology

''Ulvaria obscura'' is a common marine algae, typically identified in

algal bloom An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems. It is often recognized by the discoloration in the water from the algae's pigments. The term ''algae'' encompass ...

s referred to as "Green Tides". The species is distinct in its ability to produce the neurotransmitter dopamine as a herbivore defense mechanism. The species has a wide tolerance to various growth conditions, surviving temperatures between 5-29 °C, salinities from freshwater to complete saturation, and grows well under various light intensities. The species growth rate responds to increased dissolved inorganic nitrogen availability, making the species a possible indicator of anthropogenic pollution leading to

eutrophication Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...

Identification

The

thalli Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were ...

of ''Ulvaria obscura'' are bladelike, usually less than 5 cm tall and 8 cm thick, consisting of a single cell layer, and typically have between 2 and 6

pyrenoid Pyrenoids are sub-cellular micro-compartments found in chloroplasts of many algae,Giordano, M., Beardall, J., & Raven, J. A. (2005). CO2 concentrating mechanisms in algae: mechanisms, environmental modulation, and evolution. Annu. Rev. Plant Bio ...

s per cell. Thalli turn from green to dark brown upon desiccation due to the oxidation of dopamine within the tissues.

References

{{Taxonbar, from=Q18356255 Ulvaceae