ИСТИНА

Построить гипотезу эволюцию лофофора брахиопод, основываясь на данные по современным и ископаемым видам

The brachiopods are quite unusual and outstanding group of marine invertebrates that flourished in the Paleozoic but only 5% of the former diversity survived up to recently. Brachiopods belong to the Lophophorata group, whose synapomorphy is the presence of lophophore - the tentacle filtering organ that surrounds the mouth, but never the anus. Compared to other lophophores, the lophophore of brachiopods is characterized by a high variety of forms. Modern brachiopods have nine different structural types of this organ, from the simplest semi-ring taxoloph to the plectolophous lophophore, which consists of three hands raised into the mantle cavity. The evolution of the lophophore structure of modern brachiopods has been repeatedly discussed in the literature, and lophophore evolution schemes have been proposed, according to which the tentacle apparatus is gradually complicated, contributing to an increase in the filtration efficiency, which is necessary to increase the body size of animals. However, these schemes were built taking into account information only on modern species and are incomplete, since they do not include data on the reconstructions of the lophophore of fossil brachiopods.Therefore, a comprehensive analysis of literature data on modern and fossil brachiopods is currently required, which will allow us to propose a hypothesis for the evolution of lophophore, encompassing representatives of the entire type. Currently, the Brachiopoda type is divided into three subtypes, which differ from each other in the structure and composition of the shell, anatomy and type of ontogenesis. Representatives of the subtypes Linguliformea ​​and Craniiformea ​​are characterized by lophophore, which does not have support in the form of skeletal structures, and therefore reconstruction of its structure in extinct species is extremely difficult.Recently, imprints of the soft body, including the lophophore of some Early Cambrian representatives of linguliform brachiopods, were discovered in Chengjiang campstetts. Most of the representatives of the third subtype, Rhynchonelliformea, have a calcareous skeleton of lophophore - brachidium, which is well preserved in a fossil state. The brachidium of modern rhinchonelliform brachiopods can be represented by brachial ridges, crures, short and long loops. Despite the fact that extinct rhinchonelliform brachiopods are characterized by a much greater variety of forms of brachidium, a comparison of the structure of lophophore and its brachidium in modern forms can allow reconstruction of lophophore in extinct rhinchonelliforms with a similar type of skeletal supports.

В ходе проекта будет впервые проведен детальный анализ литературных данных по строению лофофора и его брахидиума как у современных, так и у ископаемых брахиопод, проанализированы опубликованные данные по отпечаткам мягких тканей раннекембрийских брахиопод, предложены новые типы лофофора для ископаемых форм и проведен анализ эволюции щупальцевого аппарата брахиопод от раннего кембрия до наших дней.

У заявителя проекта имеется несколько статей об анатомии, тонком строении и эволюции лофофора брахиопод. Впервые получены данные о строении мышечной и нервной системы спиролофного лофофора Hemithiris psittacea, изучен механизм фильтрации плектолофного лофофора. На основе оригинальных данных о строении лофофора дисцинид, предложена гипотеза эволюции лофофора современных брахиопод. Заявитель является создателем лекционно-практического курса по брахиоподам на биологическом факультете МГУ им. М.В. Ломоносова (http://invert.bio.msu.ru/ru/education-ru/magistracy/164-phoronida-brachiopoda-bryozoa). Автором проекта опубликована статья о реконструкции онтогенеза вымершего класса брахиопод Strophomenata. Перечень публикации автора заявки: 1. Kuzmina T.V., Temereva E.N. 2018. Organization of the lophophore in the deep-sea brachiopod Pelagodiscus atlanticus and evolution of the lophophore // Organisms Diversity and Evolution. V. 19. P. 31-39. DOI 10.1007/s13127-018-0388-0 2. Madison A.A., Kuzmina T.V. 2018 The tube‐like structures on the juvenile shells of earliest strophomenides and billingsellides as evidence of their life cycles // Lethaia (United Kingdom) DOI 10.1111/let.12342 3. Kuzmina T.V., Temereva E.N. 2018. Rejection Mechanism of Plectolophous Lophophore of Brachiopod Coptothyris grayi (Terebratulida, Rhynchonelliformea) // Moscow University Biological Sciences Bulletin. V. 73, № 3, P. 136-141 DOI 10.3103/S0096392518030100 4. Kuzmina T.V., Temereva E.N., Malakhov V.V. 2018. Ultrastructure of the lophophoral coelomic lining in the brachiopod Hemithiris psittacea: functional and evolutionary significance // Zoomorphology. V. 137. № 2. P. 257-272 DOI 10.1007/s00435-018-0397-8 5. Temereva E.N., Kuzmina T.V. 2017. The first data on the innervation of the lophophore in the rhynchonelliform brachiopod Hemithiris psittacea: What is the ground pattern of the lophophore in lophophorates? // BMC Evolutionary Biology. V. 17. № 172. P. 1-19 DOI 10.1186/s12862-017-1029-5

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