Transformation of Baikal sponges (family Lubomirskiidae) after penetration into the Angara River

• Published in: Russian journal of genetics Vol. 53; no. 12; pp. 1343 - 1349
• Main Authors: Maikova, O. O., Bukshuk, N. A., Itskovich, V. B., Khanaev, I. V., Nebesnykh, I. A., Onishchuk, N. A., Sherbakov, D. Yu
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-12-2017
• Subjects: Animal Genetics; Animal Genetics and Genomics; Biomedical and Life Sciences; Biomedicine; Human Genetics; Microbial Genetics and Genomics; noncoding mitochondrial DNA regions; ITS; sponges; morphological plasticity; Baikal
• ISSN: 1022-7954; 1608-3369
• DOI: 10.1134/S1022795417120092

Genetic and morphological analysis of endemic sponges of the Lubomirskiidae family from Lake Baikal and the upper reaches of the Angara River was performed. Various sponge species acquired a number of similar morphological traits after the transition from the lake into the river. These traits enabled an increase of sponge skeleton strength under the conditions of elevated hydrodynamic activity. The changes significantly impeded morphology-based species identification of Angara sponges. Phylogenetic analysis of ITS regions and noncoding mitochondrial DNA fragments confirmed that the Angara sponges belonged to the Baikalian Lubomirskiidae family and demonstrated the polyphyletic origin of the sponges. The use of combined molecular and morphological data allowed for the clustering of some sponge samples into groups that corresponded to individual species. The absence of genetic isolation between the
Baikalospongia intermedia
and
Lubomirskia baicalensis
species was demonstrated, whereas the
B. intermedia profundalis
subspecies was well separated from
B. intermedia
. This finding pointed to the necessity of further studies for the clarification of the taxonomic status of this subspecies.