Under Construction


Jan Votýpka
Containing group: Haemohormidiidae


Haemohormidium Henry, 1910

Type species Haemohormidium cotti Henry, 1910

Merogony occurs in the blood cells of fish (reptiles, amphibians, birds are also rarely mentioned as hosts) and results in the formation of four nucleated merozoites without the endosome. Vectors are unknown (leaches being suspected vectors), as well as other stages.  The number of valid species is uncertain; several authors speculate about the validity of the genus Haemohormidium and demonstrated the absence of ultrastructural features characteristic of the phylum Apicomplexa (Siddall et al., 1994). Levine (1988) reassigned B. anseris and B. gallinarum to the genus Haemohormidium; however, this move appears to have been erroneous (Pierce 2000) since all other species of this genus occur in poikilotherms, especially fish, and since the morphology of species in fish differs from those of birds.

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This page is being developed as part of the Tree of Life Web Project Protist Diversity Workshop, co-sponsored by the Canadian Institute for Advanced Research (CIFAR) program in Integrated Microbial Biodiversity and the Tula Foundation.

Jan Votýpka
Department of Parasitology, Charles University

Correspondence regarding this page should be directed to Jan Votępka at

Page: Tree of Life Haemohormidium. Authored by Jan Votępka. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Votýpka, Jan. 2011. Haemohormidium. Version 18 May 2011 (under construction). http://tolweb.org/Haemohormidium/68093/2011.05.18 in The Tree of Life Web Project, http://tolweb.org/

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