Encyclopedia of Parasitology

2016 Edition
| Editors: Heinz Mehlhorn

Intraconoidal Microtubules

Reference work entry
DOI: https://doi.org/10.1007/978-3-662-43978-4_4707

Motile stages of some Apicomplexa (e.g., merozoites, sporozoites, tachyzoites, bradyzoites, cystozoites) possess a protrudable  conoid, which possesses two preconoidal rings, but it is always absent in similar stages of the genera   Plasmodium ,   Theileria , and   Babesia . Besides the ductules of the  rhoptries two single (conoidal) microtubules pass the inner of the conoid reaching until the apical cell membrane. Their function is not yet understood. It might be that they are phylogenetic remnants, since they have also been proven recently in non-apicomplexan protozoans such as the photoautotrophic species Chromera velia (lives in coral banks). This flagellated species has also a conoid, which, however, is open along the side (proximal to a groove) of the protruding flagellum.

Further Reading

  1. Portman N, Slapeta J (2014) The flagellar contribution to the apical complex: a new tool for the eukaryotic Swiss army knife? Trends Parasitol 30:58–64CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Institut für Zoomorphologie, Zellbiologie und ParasitologieHeinrich-Heine-UniversitätDüsseldorfGermany