Under Construction

Guillardia theta | Hanusia phi

Kerstin Hoef-Emden and John M. Archibald
Containing group: Cryptomonads



Discussion of Phylogenetic Relationships

Since only one strain of each genus has been examined thus far, there is insufficient data to identify potential dimorphisms or inconsistencies in systematics (Marin et al. 1998; Deane et al. 2002; Hoef-Emden et al. 2002). Guillardia theta strain CCMP327 was the model cryptophyte chosen for first nuclear genome sequencing projects. Its complete nucleomorph and plastid genomes have been sequenced (Douglas and Penny 1999; Douglas et al. 2001).


Deane JA, Hill DRA, Brett SJ, McFadden GI (1998) Hanusia phi gen. et sp. nov. (Cryptophyceae): characterization of 'Cryptomonas sp. φ'. Eur. J. Phycol. 33: 149-154

Deane JA, Hill DRA, Brett SJ, McFadden GI (2002) Cryptomonad evolution: Nuclear 18S rDNA phylogeny versus cell morphology and pigmentation. J. Phycol. 38: 1236-1244

Douglas SE, Penny SL (1999) The plastid genome of the cryptophyte alga, Guillardia theta: Complete sequence and conserved synteny groups confirm its common ancestry with red algae. J. Mol. Evol. 48: 236-244

Douglas SE, Zauner S, Fraunholz M, Beaton M, Penny S, Deng LT, Wu X, Reith M, Cavalier-Smith T, Maier UG (2001) The highly reduced genome of an enslaved algal nucleus. Nature 410: 1090-1096

Gillott MA, Gibbs SP (1983) Comparison of the flagellar rootlets and periplast in two marine cryptophytes. Can. J. Bot. 61: 1964-1978

Hill DRA, Wetherbee R (1990) Guillardia theta gen. et sp. nov. (Cryptophyceae). Can. J. Bot. 68: 1873-1876

Marin B, Klingberg M, Melkonian M (1998) Phylogenetic relationships among the Cryptophyta: analyses of nuclear-encoded SSU rRNA sequences support the monophyly of extant plastid-containing lineages. Protist 149: 265-276

About This Page

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.

Kerstin Hoef-Emden
Universität zu Köln, Köln, Germany

John M. Archibald
Dalhousie University, Halifax, Nova Scotia, Canada

Correspondence regarding this page should be directed to Kerstin Hoef-Emden at and John M. Archibald at

Page: Tree of Life Guillardia theta | Hanusia phi. Authored by Kerstin Hoef-Emden and John M. Archibald. 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:

Hoef-Emden, Kerstin and John M. Archibald. 2008. Guillardia theta | Hanusia phi. Version 14 September 2008 (under construction). http://tolweb.org/Guillardia_theta_%7C_Hanusia_phi/128688/2008.09.14 in The Tree of Life Web Project, http://tolweb.org/

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