Vanvoorstia bennettiana
Encyclopedia
Bennett's Seaweed is an extinct red alga from Australia
. It is named after naturalist George Bennett.
. It can be distinguished from other members of its genus by its small size and by the structure of its reproductive organs. The overall structure of the alga is that of a blade with fine meshing. For much of the time it was extant, the alga was common.
The alga has only been found in two localities; both in or near Sydney Harbour
. One was near the eastern part of Spectacle Island, where it was discovered between May 1 and May 15, 1855. The other was in a channel between Point Piper and Shark Island, where numerous specimens were collected in 1886.
level in Sydney Harbour. Fine-meshed alga species are especially vulnerable to this type of disturbance because the particulate matter can often clog the blade and prevent light necessary for photosynthesis from reaching the organism.
A search by Arthur Lucas in 1916 failed to find the species. Since it had been only found in two places, V. bennettiana went extinct by then. The causes were human disturbance, habitat destruction
, and pollution
. Searches along the entire coastline of New South Wales
failed to locate the species.
Vanvoorstia bennettiana was, until an update in 2007, the only protist
anywhere on the IUCN's Redlist
.
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. It is named after naturalist George Bennett.
Biology
Vanvoorstia bennetiana was a small red alga. Like other members of its genus, V. bennettiana did not have significant differences in morphology throughout any phase of its life cycleBiological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
. It can be distinguished from other members of its genus by its small size and by the structure of its reproductive organs. The overall structure of the alga is that of a blade with fine meshing. For much of the time it was extant, the alga was common.
The alga has only been found in two localities; both in or near Sydney Harbour
Port Jackson
Port Jackson, containing Sydney Harbour, is the natural harbour of Sydney, Australia. It is known for its beauty, and in particular, as the location of the Sydney Opera House and Sydney Harbour Bridge...
. One was near the eastern part of Spectacle Island, where it was discovered between May 1 and May 15, 1855. The other was in a channel between Point Piper and Shark Island, where numerous specimens were collected in 1886.
Extinction
Since the V. bennettianas discovery, Sydney Harbour has been massively altered by human activities. These activities substantially increased the siltationSiltation
Siltation is the pollution of water by fine particulate terrestrial clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments, and to the increased accumulation of fine sediments on bottoms where they are undesirable...
level in Sydney Harbour. Fine-meshed alga species are especially vulnerable to this type of disturbance because the particulate matter can often clog the blade and prevent light necessary for photosynthesis from reaching the organism.
A search by Arthur Lucas in 1916 failed to find the species. Since it had been only found in two places, V. bennettiana went extinct by then. The causes were human disturbance, habitat destruction
Habitat destruction
Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity mainly for the purpose of...
, and pollution
Water pollution
Water pollution is the contamination of water bodies . Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds....
. Searches along the entire coastline of New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
failed to locate the species.
Vanvoorstia bennettiana was, until an update in 2007, the only protist
Protist
Protists are a diverse group of eukaryotic microorganisms. Historically, protists were treated as the kingdom Protista, which includes mostly unicellular organisms that do not fit into the other kingdoms, but this group is contested in modern taxonomy...
anywhere on the IUCN's Redlist
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
.