The nervous system of the lophophore in the ctenostome Amathia gracilis provides insight into the morphology of ancestral ectoprocts and the monophyly of the lophophorates

@article{Temereva2016TheNS,
  title={The nervous system of the lophophore in the ctenostome Amathia gracilis provides insight into the morphology of ancestral ectoprocts and the monophyly of the lophophorates},
  author={Elena N. Temereva and Igor A. Kosevich},
  journal={BMC Evolutionary Biology},
  year={2016},
  volume={16}
}
BackgroundThe Bryozoa (=Ectoprocta) is a large group of bilaterians that exhibit great variability in the innervation of tentacles and in the organization of the cerebral ganglion. Investigations of bryozoans from different groups may contribute to the reconstruction of the bryozoan nervous system bauplan. A detailed investigation of the polypide nervous system of the ctenostome bryozoan Amathia gracilis is reported here.ResultsThe cerebral ganglion displays prominent zonality and has at least… 
Organization of the lophophoral nervous system in the cyclostome bryozoans confirms the relationship of the Bryozoa and Brachiozoa
The phylogeny of bryozoans is ambiguous and apparently cannot be resolved by molecular methods alone. Morphological data from previously unstudied species may help establishing relationships between
Innervation of the lophophore suggests that the phoronid Phoronis ovalis is a link between phoronids and bryozoans
The validity of the Lophophorata as a monophyletic group remains controversial. New data on the innervation of the lophophore, which is a unique feature of the lophophorates, may help clarify the
Unusual lophophore innervation in ctenostome Flustrellidra hispida (Bryozoa).
TLDR
The presence of the outer nerve ring participating in the innervation of tentacles makes the F. hispida lophophore nervous system particularly similar to the lophophile nervous system of phoronids, which allows to suggest that it may reflect the ancestral state for all bryozoans.
Peculiarities of Tentacle Innervation of Flustrellidra hispida and Evolution of Lophophore in Bryozoa
TLDR
The evolutionary transformation from a hypothetical phoronida-like ancestor lophophore bearing a prominent outer nerve ring with numerous tentacle nerves emanating from it, to the complex bell-shaped lophphore of F. hispida with a well-pronounced outer nervous ring bearing a few Tentacle nerves is suggested.
The neuroanatomy of Barentsia discreta (Entoprocta, Coloniales) reveals significant differences between bryozoan and entoproct nervous systems
TLDR
The neuroanatomy of the colonial Barentsia discreta is generally similar to that of solitary entoprocts but differs in the anatomy and ultrastructure of the ganglion, the number of neurite bundles in the calyx, and the distribution of serotonin in the nerve elements.
The nervous system of the most complex lophophore provides new insights into the evolution of Brachiopoda
TLDR
The innervation of the most complex lophophore (the plectolophe) of the rhynchonelliform species Coptothyris grayi is described, which has undergone simplification, i.e., the absence of the accessory brachial nerve, which is apparently correlated with a reduction in the complexity of the lphophore’s musculature.
Neuroanatomy of Hyalinella punctata: Common patterns and new characters in phylactolaemate bryozoans
TLDR
The nervous system of Hyalinella punctata is characterized with immunocytochemical techniques and confocal laser scanning microscopy for the first time, finding that having a diffuse nerve plexus may represent an ancestral feature for freshwater bryozoans.
The non-brain anterior nerve center and tentacle crown structure of Owenia borealis (Annelida, Oweniidae): the evolution of the nervous system and tentacles in Bilateria
TLDR
Results suggest that the ultra anatomy of that plexus brain in O. borealis and other oweniids with tentacles might be a stratified neuroepithelium, which could reflect the simplification of structure of the anterior nerve center in some bilaterian lineages.
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?
TLDR
The innervation of the lophophore in the rhynchonelliform Hemithiris psittacea differs from that in the inarticulate Lingula anatina in several ways and is suggested to have had a simple shape but many nerve elements.
First data on the organization of the nervous system in juveniles of Novocrania anomala (Brachiopoda, Craniiformea)
TLDR
The results suggest that ‘phoronid-like’ non-specialized tentacles may be regarded as the ancestral type of tentacles for brachiopods and probably for all lophophorates.
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