Место издания:The Technical University Liberec, Czech Republic
Первая страница:109
Аннотация:The lophophore is the main synapomorphy of the lophophorates, whose monophyly is not supported by many recent data of molecular phylogeny. At the same time, some morphological data evidence the presence of homologous elements in the nervous system of the lophophore in phoronids, brachiopods, and bryozoans. Because the organization of the lophophoral musculature may also provide insight into lophophorates relationship, myoanatomy of poorly studied groups such as phoronids warrants detailed investigation. Original data on phoronid lophophoral myoanatomy were obtained in four phoronid species with different morphology of the lophophore: Phoronis ovalis, Phoronis ijimai, Phoronis australis, Phoronopsis harmeri. Although the myoanatomy of the lophophore differs in details, it exhibits the similar ground plan, which is four-partitioned and includes (i) frontal and abfrontal muscles of the tentacles that connect to (ii) distal paired groups of muscles of tentacular lamina and (iii) longitudinal muscles of tentacular lamina that connect with (iv) the circular muscle. Comparative analysis revealed that the same four-partitioned ground plan may be found in all main groups of bryozoans; it includes (i) frontal and abfrontal tentacle muscles that connect with (ii) paired muscle sets, either one pair of inverted V-shaped muscles (in Stenolaemata and Phylactolaemata) or two pairs of V- and then inverted V-shaped muscles (in Gymnolaemata); and (iii) a single median muscle (most often referred to as buccal or oral dilatator) that connects to (iv) the pharyngeal circular muscles. The four-partitioned ground plan of the lophophoral musculature in phoronids and in bryozoans indicates the homology of the lophophore and the monophyly of the lophophorates as a united clade that includes Phoronida, Bryozoa, and Brachiopoda. This study is supported by Russian Science Foundation (#18-14-00082).
