Search results for "Spongillidae"
showing 3 items of 3 documents
Ingestion, digestion, and egestion in Spongilla lacustris (Porifera, Spongillidae) after pulse feeding with Chlamydomonas reinhardtii (Volvocales)
1993
The route followed by food particles in Spongilla lacustris was clarified by light and electron microscopic examination of sponges fed with Chlamydomonas reinhardtii. The algal cells are phagocytosed by prosendopinacocytes and choanocytes. After some time they are transferred to archaeocytes, amoebocytes, and lophocytes. Changes in algal structure during digestion were observed and the egestion of algal remnants was documented in life for the first time. In light micrographs, digestion of the algal cells is manifest first in shrinkage of the cells, then in disintegration to form several spherical green fragments 2–3 μm in diameter, and finally, after 12–18 h, in a reddish brown discoloratio…
Molecular phylogeny of the freshwater sponges in Lake Baikal
2003
The phylogenetic relationship of the freshwater sponges (Porifera) in Lake Baikal is not well understood. A polyphyletic and/or monophyletic origin have been proposed. The (endemic) Baikalian sponges have been subdivided into two families: endemic Lubomirskiidae and cosmopolitan Spongillidae. In the present study, two new approaches have been made to resolve the phylogenetic relationship of Baikalian sponges; analysis of (1) nucleotide sequences from one mitochondrial gene, the cytochrome oxidase subunit I (COI) and of (2) one selected intron from the tubulin gene. Specimens from the following endemic Baikalian sponge species have been studied; Lubomirskia baicalensis, Baikalospongia interm…
Speciation of sponges in Baikal-Tuva region: an outline
2006
Lake Baikal is known for its high percentage of endemic fauna and flora. The most abundant sessile animal taxa in the littoral zone of Baikal are the photosymbiotic sponges. These endemic sponges are grouped to the family Lubomirskiidae and are separated, based on molecular data, from the cosmopolitan family Spongillidae Gray 1867. In the present review, recent data on the potential driving forces of the rapid speciation in Lake Baikal have been unified. Current data suggest that the genetic repertoire of the sponges was sufficiently large to cope with the major cold events, occurring 2.8–2.5 and 1.8–1.5 Ma. It is proposed that during those periods of climatic incisions founder populations …