Rhodophyta, Order: Bangiales; Family: Bangiaceae. The Bangia fuscopurpurea is the only species in this genus.

Etymology

Fuscopurpurea fuscous means ‘brown’ and purpura means  ‘purplish’ - describing the algal colour.

Description

Individuals belonging to the species are soft, filamentous  and unbranched. They contain a row or several rows of  cells.

Size

The thallus is less than 1 mm in width and is several  centimeters in length.

Colour

The Bangia fuscopurpurea appears in shades of black.

Special features

The Bangia fuscopurpurea is darkly shaded, smooth and  inhabits polluted beaches. It resembles bluegreen division  algae, and may be mistaken for them.

Habitat

The Bangia fuscopurpurea prefers polluted habitats. It  grows in either fresh or salty water, and it transplants swiftly  from one to the other. The cells are destroyed, but if done  gradually, the alga can adapt to its new habitat. As expected,  the spores are more resilient than the thallus to such  changes. At one point, it was believed that the genus  incorporated two species, but lately it has been proved that

 

 

Photo by Shlomit Katz.  Bangia fuscopurpurea  right: cellular arrangement of the thallus  left: general view.  individuals growing in fresh water and those growing in  salt water belong to the same biological species.

Biology and reproduction

The Bangia fuscopurpurea’s life cycle resembles that of  the porphyra. The life cycle of this species has also been  described, including its microscopic stage (conchocelis),  which develops upon the shell of a snail. The life cycle,  especially the germination stage, is affected by the duration  of daylight, and it quickly responds to environmental  change. Sexual reproduction is very rare.

Individuals are quite different at various stages of their life  cycle. Haploid and diploid individuals (with either one or  two chromosome structures) have been found, and  sometimes, the same thallus is haploid in its lower region  and diploid further up. Colonies with different chromosome  numbers have been found in various parts of the world.

Seasonality and distribution

The Bangia fuscopurpurea is found on Eastern  Mediterranean shores in winter and spring. It is  internationally distributed and found in nearly every sea in  the world, including some fresh water reservoirs.

Additional species

The number of species in this genus often changes. At  present, nine species are numbered, although in the past it  was believed that only one or two species existed, and these  grew in different habitats (saline and fresh waters). In this  region:

Bangia atropurpurea (Roth) C. Agardh  = Bangia fuscopurpurea (Dillwyn) Lyngbye has been  reported.

 

Photo by Shlomit Katz.