Unusual body division and epithelium structure in unusual phoronid Phoronis embryolabi.

Phoronida is a small phylum of benthic marine invertebrates that can occur in large numbers globally. The study of phoronid morphology and anatomy is important for understanding phoronid biology and the function of benthic communities dominated by phoronids. Because all phoronids are tube-living animals, the study of the morphology and ultrastructure of the body wall is an important step toward understanding the processes of the tube formation, growth, and renovation.

First Detection of Podocytes in the Circulatory System of Enigmatic Echiurids (Annelida: Thalassematidae).

The fine structure of echiurid blood vessels in the proboscis is known in detail, but the circulatory system of the trunk is still understood mainly at the level of general anatomy. The trunk circulatory system was studied in Bonellia viridis females, and specialized podocytes were found to form the walls of the ring vessel and the anterior part of the ventral vessel. Podocytes were for the first time described in the echiurid circulatory system.

Structure of the oral tentacles of early ontogeny stage in brachiopod Hemithiris psittacea (Rhynchonelliformea, Rhynchonellida).

Brachiopods have the most complex lophophore in comparison with other lophophorates, i.e., phoronids and bryozoans.

Revision of the muscular system in the brachiopod Novocrania anomala using 3D reconstruction: Functional and paleontological significance.

The musculature is one of the best studied organ systems in brachiopods, being approachable not only by dissecting recent species of brachiopods, but also by exploring muscle scars in fossil material. In the present study, the muscular anatomy of Novocrania anomala is studied using 3D reconstructions based on microcomputed tomography. Muscles of N.

Two Sources of Mesoderm in Brachiopods.

In Bilateria, the formation of the coelomic mesoderm occurs in various ways and is of great significance for comparative embryology and phylogeny. Several early ontogenetic stages were studied in the brachiopod Coptothyris grayi by scanning electron microscopy and cytochemistry combined with confocal laser microscopy. Two sources of the mesoderm were observed to form simultaneously from the anterior and posterior walls of the archenteron at the gastrula stage.