Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Body cavities in bryozoans : Functional and phylogenetic implications. / Shunatova, Natalia; Tamberg, Yuta.
в: Journal of Morphology, Том 280, № 9, 2019, стр. 1332-1358.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Body cavities in bryozoans
T2 - Functional and phylogenetic implications
AU - Shunatova, Natalia
AU - Tamberg, Yuta
PY - 2019
Y1 - 2019
N2 - Based on morphological evidence, Bryozoa together with Phoronida and Brachiopoda are traditionally combined in the group Lophophorata, although this view has been recently challenged by molecular studies. The core of the concept lies in the presence of the lophophore as well as the nature and arrangement of the body cavities. Bryozoa are the least known in this respect. Here, we focused on the fine structure of the body cavity in 12 bryozoan species: 6 gymnolaemates, 3 stenolaemates and 3 phylactolaemates. In gymnolaemates, the complete epithelial lining of the body cavity is restricted to the lophophore, gut walls, and tentacle sheath. By contrast, the cystid walls are composed only of the ectocyst-producing epidermis without a coelothelium, or an underlying extracellular matrix; only the storage cells and cells of the funicular system contact the epidermis. The nature of the main body cavity in gymnolaemates is unique and may be considered as a secondarily modified coelom. In cyclostomes, both the lophophoral and endosaccal cavities are completely lined with coelothelium, while the exosaccal cavity only has the epidermis along the cystid wall. In gymnolaemates, the lophophore and trunk cavities are divided by an incomplete septum and communicate through two pores. In cyclostomes, the septum has a similar location, but no openings. In Phylactolaemata, the body cavity is undivided: the lophophore and trunk coeloms merge at the bases of the lophophore arms, the epistome cavity joins the trunk, and the forked canal opens into the arm coelom. The coelomic lining of the body is complete except for the epistome, lophophoral arms, and the basal portions of the tentacles, where the cells do not interlock perfectly (this design probably facilitates the ammonia excretion). The observed partitioning of the body cavity in bryozoans differs from that in phoronids and brachiopods, and contradicts the Lophophorata concept.
AB - Based on morphological evidence, Bryozoa together with Phoronida and Brachiopoda are traditionally combined in the group Lophophorata, although this view has been recently challenged by molecular studies. The core of the concept lies in the presence of the lophophore as well as the nature and arrangement of the body cavities. Bryozoa are the least known in this respect. Here, we focused on the fine structure of the body cavity in 12 bryozoan species: 6 gymnolaemates, 3 stenolaemates and 3 phylactolaemates. In gymnolaemates, the complete epithelial lining of the body cavity is restricted to the lophophore, gut walls, and tentacle sheath. By contrast, the cystid walls are composed only of the ectocyst-producing epidermis without a coelothelium, or an underlying extracellular matrix; only the storage cells and cells of the funicular system contact the epidermis. The nature of the main body cavity in gymnolaemates is unique and may be considered as a secondarily modified coelom. In cyclostomes, both the lophophoral and endosaccal cavities are completely lined with coelothelium, while the exosaccal cavity only has the epidermis along the cystid wall. In gymnolaemates, the lophophore and trunk cavities are divided by an incomplete septum and communicate through two pores. In cyclostomes, the septum has a similar location, but no openings. In Phylactolaemata, the body cavity is undivided: the lophophore and trunk coeloms merge at the bases of the lophophore arms, the epistome cavity joins the trunk, and the forked canal opens into the arm coelom. The coelomic lining of the body is complete except for the epistome, lophophoral arms, and the basal portions of the tentacles, where the cells do not interlock perfectly (this design probably facilitates the ammonia excretion). The observed partitioning of the body cavity in bryozoans differs from that in phoronids and brachiopods, and contradicts the Lophophorata concept.
KW - Bryozoa
KW - coelom
KW - excretion
KW - Lophophorata
KW - nutrient transport
KW - NERVOUS-SYSTEM
KW - PHORONIDA
KW - 18S RIBOSOMAL DNA
KW - MOLECULAR PHYLOGENY
KW - WALL MORPHOLOGY
KW - CHEILOSTOME BRYOZOA
KW - LOPHOPHORE
KW - BRACHIOPODS
KW - ULTRASTRUCTURE
KW - FRONTAL WALL
UR - http://www.scopus.com/inward/record.url?scp=85068222531&partnerID=8YFLogxK
U2 - 10.1002/jmor.21034
DO - 10.1002/jmor.21034
M3 - Article
C2 - 31251428
AN - SCOPUS:85068222531
VL - 280
SP - 1332
EP - 1358
JO - Journal of Morphology
JF - Journal of Morphology
SN - 0362-2525
IS - 9
ER -
ID: 45771218