ИСТИНА

According to recent data, the world fauna of phoronids contains 12 species. Eight phoronid species have well described planktotrophic larvae. The analysis of literature data showed the existence of 39 varieties of planktotrophic phoronid larvae. According to own novel morphological and molecular results, in addition to eight known phoronid larvae, there are at least four varieties of actinotrochs, which have unique combination of distinctive features and were discovered in different areas of the World Ocean: [Actinotrocha D], [Actinotrocha architecta], [Actinotrocha C], [Actinotrocha] sp. We have obtained molecular results for one of these varieties – [Actinotrocha] sp., which was collected in the Vostok Bay Sea of Japan (June-August, 2002-2011). This larva is very similar to larvae of [Phoronis pallida] and [Phoronis psammophila], but has other distinctive features. [Actinotrocha] sp. is opaque, has 0.7 mm of body length, eight tentacles, three blood masses, strong pigmentation of the unpaired stomach diverticulum, and adult tentacles, which look like small sacks under the basis of larval tentacles. The analyses of sequencing data (SSU, LSU, cox1) showed that this larva does not belong to any adult phoronids, which are exposed in Gen Bank. The distribution of actinotrochs is very poor studied. The most of actinotrochs were described along the Pacific coast of North America (NA), in North Sea, Mediterranean, Black Sea, along Pacific coast of Eurasia and Japan. There are rare data about actinotrochs along Atlantic coast of NA and Brasil and in the Indian Ocean.