Skip to main content
SpringerLink
Log in

Two types of the tentacle structure of Entoprocta and the fine structure of the vestibular groove

  • Original Paper
  • Published:
Zoomorphology Aims and scope Submit manuscript

Abstract

The structure of the filtration apparatus of Entoprocta has been mainly investigated by light microscopy. The ultrastructure of the tentacles has been investigated in detail in only one species, Loxosomella elegans, and the ultrastructure of the cells of the vestibular groove has not been described at all. In this paper, the structures of the filtration apparatuses of two species are studied: the colonial species Pedicellina cernua (Pallas, 1774) (Entoprocta, Coloniales) and the solitary species Loxosomella nordgaardi Ryland 1961 (Entoprocta, Solitaria). The ultrastructure of the epidermis of the tentacles, as well as sensitive organs, muscles and nerve fibers, is described in detail. A comparison of the structures of tentacles of different species facilitated distinguishing two possible variants of organization of the tentacle—one with the frontal groove and one without the frontal groove, depending on the size of the calyx and tentacles. Some differences are also noted in the ultrastructure of the abfrontal cells of the tentacles in colonial and solitary species, which possibly determine the differences in the process of contraction of the tentacles. In some cases, the tentacles only bend without changing their length, and in other cases, they also shorten. The ciliary vestibular groove lies at the base of the tentacles. It was noted that the ciliary rows of the tentacles continue as the ciliary cells of the rims and walls of the groove. The ultrastructure of the cells of the rim of the groove is similar to the ultrastructure of the lateral cells of the tentacles. The cells of the walls of the groove are similar to the frontal cells of the tentacles. The cells of the bottom of the groove differ from all types of cells of the tentacles.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

Similar content being viewed by others

References

  • Atkins D (1932a) The ciliary feeding mechanism of the Entoproct Polyzoa, and a comparison with that of the Ectoproct Polyzoa. Q J Microsc Sci 75:393–423

    Google Scholar 

  • Atkins D (1932b) The loxosomatidae of the plymouth area including L. obesum sp. nov. Q J Microsc Sci 75:321–391

    Google Scholar 

  • Borisanova AO (2016a) A new species of solitary Entoprocta, Loxosomella angusta sp.n., from the White Sea. Invertebr Zool 13:43–50

    Article  Google Scholar 

  • Borisanova AO (2016b) Emschermannia ramificata—a new genus and species of solitary entoproct from the Kara Sea, Russia. Zootaxa 4084:135–142

    Article  PubMed  Google Scholar 

  • Borisanova AO (2018) Entoprocta (Kamptozoa). In: Schmidt-Rhaesa A (ed) Handbook of zoology. Miscellaneous invertebrates. De Gruyter, Berlin, pp 111–162

    Google Scholar 

  • Borisanova AO, Krylova EM (2014) A new species of Loxosomatidae (Entoprocta, Solitaria) from the White Sea: Loxosomella unicornis sp. nov. Zootaxa 3861:290–296

    Article  PubMed  Google Scholar 

  • Borisanova AO, Potanina DM (2016) A new species of Coriella, Coriella chernyshevi n. sp. (Entoprocta, Barentsiidae), with comments on the genera Coriella and Pedicellinopsis. Zootaxa 4184:376–382

    Article  PubMed  Google Scholar 

  • Borisanova AO, Malakhov VV, Temereva EN (2019) The neuroanatomy of Barentsia discreta (Entoprocta, Coloniales) reveals significant differences between bryozoan and entoproct nervous systems. Front Zool 16:9

    Article  PubMed  PubMed Central  Google Scholar 

  • Borisanova AO, Chernyshev AV, Ekimova IA (2018) Deep-sea Entoprocta from the Sea of Okhotsk and the adjacent open Pacific abyssal area: new species and new taxa of host animals. Deep Sea Res Part II 154:87–98

    Article  CAS  Google Scholar 

  • Brien P (1959) Classe des Endoproctes ou Kamptozoaries. In: Pierre-P G (ed) Traité de Zoologie, vol 5. Masson et Cie, Paris, pp 927–1007

    Google Scholar 

  • Emschermann P (1982) Les Kamptozoaires. État actuel de nos connaissances sur leur anatomie leur development, leur biologie et leur position phylogénétique. Soc Zool Fr 107:317–344

    Google Scholar 

  • Franzén Å (1973) Some Antarctic Entoprocta with notes on morphology and taxonomy in the Entoprocta in general. Zool Scr 2:183–195

    Article  Google Scholar 

  • Fuchs J, Bright M, Funch P, Wanninger A (2006) Immunocytochemistry of the neuromuscular systems of Loxosomella vivipara and L. parguerensis (Entoprocta: Loxosomatidae). J Morphol 267:866–883

    Article  PubMed  Google Scholar 

  • Hyman LH (1951) The invertebrates. Acanthocephala, Aschelminthes and Entoprocta. The pseudocoelomate Bilateralia, vol 3. McGraw-Hill, London

    Google Scholar 

  • Mariscal RN (1965) The adult and larval morphology and life history of the Entoproct Barentsia gracilis (M. Sars, 1835). J Morphol 116:311–338

    Article  CAS  PubMed  Google Scholar 

  • Nickerson WS (1901) On Loxosoma davenporti sp.nov. an entoproct from the New England coast. J Morphol 17:351–381

    Article  Google Scholar 

  • Nielsen C (1964) Studies on Danish Entoprocta. Ophelia 1:1–76

    Article  Google Scholar 

  • Nielsen C (1966) Some Loxosomatidae (Entoprocta) from the Atlantic coast of the United States. Ophelia 3:249–275

    Article  Google Scholar 

  • Nielsen C (1989) Entoprocts: keys and notes for the identification of the species. Synop Br Fauna (New Ser) 41:1–131

    Google Scholar 

  • Nielsen C (1996) Three new species of Loxosoma (Entoprocta) from Phuket, Thailand, with a review of the genus. Zool Scr 25:61–75

    Article  Google Scholar 

  • Nielsen C, Jespersen Å (1997) Entoprocta. In: Harrison FW, Ruppert EE (eds) Microscopic anatomy of invertebrates, vol 13. Wiley-Liss, New York, pp 13–43

    Google Scholar 

  • Nielsen C, Rostgaard J (1976) Structure and function of an entoproct tentacle with a discussion of ciliary feeding types. Ophelia 15:115–140

    Article  Google Scholar 

  • Riisgard HU, Nielsen C, Larsen PS (2000) Downstream collecting in ciliary suspension feeders: the catch-up principle. Mar Ecol Prog Ser 207:33–51

    Article  Google Scholar 

Download references

Acknowledgements

The author is grateful to the SCUBA-Diving Team of White Sea Biological Station for collecting the material. The author is thankful to Alexander Semenov for the photo of a living colony of Pedicellina cernua. The research was supported by the Russian Science Foundation (project no. 18-14-00082).

Author information

Authors and Affiliations

  1. Invertebrate Zoology Department, Biological Faculty, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia

    A. O. Borisanova

Authors
  1. A. O. Borisanova
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to A. O. Borisanova.

Ethics declarations

Conflict of interest

The author declares that she does not have competing interests.

Ethics approval

The use of entoprocts in the laboratory does not raise any ethical issues, and therefore approval from regional and local research ethics committees is not required. The field sampling did not involve endangered or protected species. In accordance with local guidelines, permission for collection of material was not required.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Borisanova, A.O. Two types of the tentacle structure of Entoprocta and the fine structure of the vestibular groove. Zoomorphology 139, 433–445 (2020). https://doi.org/10.1007/s00435-020-00497-y

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00435-020-00497-y

Keywords

Search

Navigation