''Lubomirskia baikalensis'' is a freshwater species of
sponge
Sponges or sea sponges are primarily marine invertebrates of the animal phylum Porifera (; meaning 'pore bearer'), a basal clade and a sister taxon of the diploblasts. They are sessile filter feeders that are bound to the seabed, and a ...
that is
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to
Lake Baikal
Lake Baikal is a rift lake and the deepest lake in the world. It is situated in southern Siberia, Russia between the Federal subjects of Russia, federal subjects of Irkutsk Oblast, Irkutsk Oblasts of Russia, Oblast to the northwest and the Repu ...
, Russia. It is commonly called the Lake Baikal sponge and it is the most abundant sponge in the lake, but all the approximately 15 species of sponges in the family
Lubomirskiidae
Lubomirskiidae is a family of freshwater sponges from Lake Baikal in Russia, endemic to the lake, though there are unconfirmed reports from Lake Jegetai-Kul in the Western Sayan, along with the Bering Sea
The Bering Sea ( , ; rus, Бе́р ...
are restricted to Baikal.
''Lubomirskia baikalensis'' is found on hard bottoms at depths between .
In relatively shallow water, it is bark-like, and covers stones somewhat like a carpet.
[ From a depth of it starts to have branches,][ and can reach a height of more than , which is unusually large for a freshwater sponge.][Belikov; Kaluzhnaya; Schröder; Müller; and Müller (2007). ''Lake Baikal endemic sponge Lubomirskia baikalensis: structure and organization of the gene family of silicatein and its role in morphogenesis.'' Porifera Research: Biodiversity, Innovation and Sustainability, pp. 179-188.] On rocky grounds at depths of the branching form is particularly common and may form "forests".[ Some specimens have been observed to be non- sessile, being fragments originating from sessile stands which have broken free and drift above the soft benthic ]sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...
.symbiosis
Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two organisms of different species. The two organisms, termed symbionts, can fo ...
with a green dinoflagellate
The Dinoflagellates (), also called Dinophytes, are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered protists. Dinoflagellates are mostly marine plankton, but they are also commo ...
, making it green in appearance. Okadaic acid produced by the dinoflagellate assists the sponge to survive when Lake Baikal is iced over in winter, and the water temperature is close to .
References
External links
Picture of this species
Haplosclerida
Animals described in 1773
Fauna of Lake Baikal
Taxa named by Peter Simon Pallas
{{Demosponge-stub