Разработка молекулярного метода видовой идентификации пресноводных губок (Porifera)

УДК 593.4:575

В. Б. Ицкович*, С. М. Ефремова**, Й. Масуда***, С. И. Беликов*

*Лимнологический институт СО РАН, Иркутск, Российская Федерация, itskovich@mail.ru
**Санкт-Петербургский государственный университет,
Санкт-Петербург, Российская Федерация,
***Медицинская школа Кавасаки, Окаяма, Япония

DEVELOPMENT OF MOLECULAR METHOD FOR SPECIES IDENTIFICATION IN FRESHWATER SPONGES (PORIFERA)

V. Itskovich*, S. Efremova**, Y. Masuda***, S. Belikov*

*Limnological Institute of the Siberian Branch Of The Russian Academy of Sciences,
Irkutsk, Russia, itskovich@mail.ru
**St. Petersburg State University, St. Petersburg, Russia,
***Kawasaki Medical School, Kurashiki, Japan

Freshwater sponges are main part of benthos in ancient LakeBaikal and are important for cleaning of water due their filter activity. A high biodiversity among freshwater sponges belonging to the endemic family Lubomirskiidae inhabiting the lakeBaikal has been described. During the summers 1993–1999 several expeditions were carried out to collect freshwater sponges to review their taxonomy and distribution in LakeBaikal.

The sequences of the internal transcribed spacers (ITS1 and ITS2) of 11 species of the family Lubomirskiidae, of 13 species of the family Spongillidae and of 1 species of the family Potamolepidae were obtained to develop a molecular marker for species identification in Porifera and to study the phylogenetic relationships between endemic and cosmopolitan freshwater sponges, and the evolution of sponges in Lake Baikal. Our results indicated that the endemic family Lubomirskiidae is monophyletic, showing the highest bootstrap support. The cosmopolitan family Spongillidae is paraphyletic in relation to other freshwater sponges. The genera Radiospongilla and Eunapius are probably monophyletic and the genus Ephydatia is paraphyletic and forms basal branches.

The genetic distances between Lubomirskiidae species are much lower than those between Spongillidae species. The lower genetic distances between species of Baikalian sponges is indicative of their relatively recent radiation from a common ancestor. The evolutionary age of the family Lubomirskiidae apparently does not exceed the geological age of LakeBaikal, which indicates an autochthonous evolution of sponges in LakeBaikal.

These results indicated that ITS sequences can be useful for identification of species of freshwater sponges. Styding of species diversity of this important group of organisms will allow performing an ecological monitoring of freshwater and marine ecosystems.


Zoocenosis — 2007
 Біорізноманіття та роль тварин в екосистемах: Матеріали ІV Міжнародної наукової конференції. – Дніпропетровськ: Вид-во ДНУ, 2007. – С. 77.