Belongs within: Diaphoretickes.Contains: Bigyra, Pseudofungi, Diatomista, Chrysista, Alveolata, Cercozoa, Endomyxa, Radiozoa, Foraminifera. The Sar clade is a group of protists united by molecular data, named for the initials of the major subclades Stramenopiles, Alveolata and Rhizaria. It has been defined as the least inclusive clade containing Bigelowiella natans, Tetrahymena thermophila and Thalassiosira pseudonana but not… Continue reading Sar


Belongs within: Oligohymenophorea. The model tetrahymenidans Published 15 November 2019 Ciliates have long been one of the most (if not the most) confidently recognised groups of unicellular eukaryotes owing to their distinctive array of features, in particular locomotion by means of more or less dense tracts of small cilia that often run the length of… Continue reading Tetrahymenida


Belongs within: Mediophyceae.Contains: Stephanodiscus, Thalassiosira. United by silicon tubes Published 12 March 2024 Diatoms are among the most instantly recognised of all aquatic micro-organisms. Their architectural silica tests are unique in the microbial biosphere. They are also among the most abundant organisms in many waters and play a pivotal role in the global distribution of… Continue reading Thalassiosiraceae


Belongs within: Rotaliida.Contains: Anomalinidae, Trichohyalidae, Gavelinella, Parrelloididae, Discorbinellidae, Cancrisidae, Eponididae, Rosalinidae. The Siphoninidae are a group of Foraminifera known from the Eocene to the present, commonly bearing a frilled keel around the outer edge of the test (Loeblich & Tappan 1964). <==RosalinidaM13 |–GavelinelloideaM13 | |–AnomalinidaeM13 | |–TrichohyalidaeM13 | |–GavelinellidaeM13 | | |–GavelinellaM13 | | |–Brotzenella… Continue reading Rosalinida


Belongs within: Foraminifera. The Hyperamminidae were treated by Cushman (1940) as a family of Foraminifera with an elongate, undivided, agglutinate test. The Hippocrepininae (with test free) and Dendrophryinae (with test attached) were later placed by Loeblich & Tappan (1964) as independent subfamilies within the family Astrorhizidae; as the latter group is now known to be… Continue reading Hippocrepinida


Oxytoxum flowing The dinoflagellates are perhaps one of the better studied groups of microbial eukaryotes but there are still many subgroups of dinoflagellates that remain poorly known. One such subgroup is the genus Oxytoxum. These distinctive looking marine flagellates, though widespread, are rarely collected in large numbers. They are most associated with open waters of… Continue reading Oxytoxum


Belongs within: Sporozoa.Contains: Eimeria. The Eimeriorina are a group of intracellular parasites in which macro- and microgametes are produced independently (Adl et al. 2019). Characters (from Adl et al. 2019): Microgametes and macrogametes develop independently; syzygy is absent; microgamonts produce large number of cilated microgametes; zygote is nonmotile; sporozoites always enclosed in sporocyst within oocyst.… Continue reading Eimeriorina

Categorised as Alveolata


Belongs within: Monadofilosa. The Phaeodarea are a group of amoeboid organisms that commonly possess a skeleton of amorphous silica bound by organic material. Characters (from Adl et al. 2012): Central capsule with thickened, double-layered, capsular wall containing two kinds of pores or openings; large opening known as an “astropylum” or oral pore with a protruding… Continue reading Phaeodarea

Categorised as Cercozoa


Belongs within: Radiozoa. The Arthracanthida are a group of acanthareans that have the ecto- and endoplasm separated by a thick capsule (Adl et al. 2012). Characters (from Adl et al. 2012): Thick capsule clearly demarcates pigmented endoplasm from ectoplasm; axopodia with hexagonal microtubular arrays; many nuclei in endoplasm; algal symbionts in all known species, except… Continue reading Arthracanthida

Categorised as Radiozoa


Belongs within: Sar.Contains: Arthracanthida, Spumellaria, Nassellaria, Aculearia, Sphaerellaria, Stauraxonaria, Collodaria, Archaeospicularia, Entactinaria. The Radiozoa are a clade of aquatic protists that typically bear mineralised skeletons of silica or strontium sulphate. Sticholonche zanclea Published 6 January 2010 Sticholonche zanclea is a very unusual marine protist. In the past, it has been classified among the heliozoans, a… Continue reading Radiozoa

Categorised as Radiozoa