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Cryptists
Cryptista is a clade of algae-like eukaryotes. It is most likely related to Archaeplastida which includes plants and many algae, within the larger group Diaphoretickes. Although it has sometimes placed along with Haptista in the group Hacrobia, within the kingdom Chromista, most recent studies have found that Hacrobia is not a clade. For example, in 2016, a broad phylogenomic study found that cryptists fall within the group Archaeplastida, while haptophytes are closely related to the SAR supergroup. Taxonomy Based on studies done by Cavalier-Smith, Chao & Lewis 2015 *''Corbihelia'' ** Phylum Microheliellida Tedersoo 2017 [Endohelia Cavalier-Smith 2015] *** Class Endohelea Cavalier-Smith 2012 * Clade Cryptista s.s. ** Phylum Palpitophyta Tedersoo 2017 *** Class Palpitea Cavalier-Smith 2012 ** Clade Rollomonadia Cavalier-Smith 2013 stat. nov. *** Phylum Kathablepharidophyta Okamoto & Inouye 2005 [Leucocrypta Cavalier-Smith 2015] **** Class Leucocryptea Cavalier-Smith 2004 [Kathab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptomonada
Cryptomonada is a proposed super-class of Cryptists linking Cryptophyceae and Goniomonadea, which was first proposed by Cavalier-Smith in 2004. He made this proposal based on three shared morphological characteristics: Presence of a periplast, ejectisomes with secondary scroll, and mitochondrial cristae A crista (; plural cristae) is a fold in the inner membrane of a mitochondrion. The name is from the Latin for ''crest'' or ''plume'', and it gives the inner membrane its characteristic wrinkled shape, providing a large amount of surface area fo ... with flat tubules. Genetic studies as early as 1994 also supported the hypothesis that ''Goniomonas'' was sister to Cryptophyceae. A study in 2018 found strong evidence that the common ancestor of ''Cryptomonada'' was an autotrophic protist. References {{Taxonbar, from=Q65088966 Cryptista ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptophyceae
The cryptophyceae are a class of algae, most of which have plastids. About 220 species are known, and they are common in freshwater, and also occur in marine and brackish habitats. Each cell is around 10–50 μm in size and flattened in shape, with an anterior groove or pocket. At the edge of the pocket there are typically two slightly unequal flagella. Some exhibit mixotrophy. Characteristics Cryptophytes are distinguished by the presence of characteristic extrusomes called ejectosomes or ejectisomes, which consist of two connected spiral ribbons held under tension. If the cells are irritated either by mechanical, chemical or light stress, they discharge, propelling the cell in a zig-zag course away from the disturbance. Large ejectosomes, visible under the light microscope, are associated with the pocket; smaller ones occur underneath the periplast, the cryptophyte-specific cell surrounding. Except for ''Chilomonas'', which has leucoplasts, cryptophytes have one or two ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haptista
Haptista is a proposed group of protists made up of centrohelids and haptophytes. Phylogenomic studies indicate that Haptista, together with ''Ancoracysta twista'', forms a sister clade to the SAR+Telonemia supergroup, but it may also be sister to the Cryptista (+Archaeplastida). It is thus one of the earliest diverging Diaphoretickes. Taxonomy Based on studies done by Cavalier-Smith, Chao & Lewis 2015 and Ruggiero et al. 2015. * Subphylum Centroheliozoa Cushman & Jarvis 1929 sensu Durrschmidt & Patterson 1987 eliozoa Haeckel 1862 stat. n. Margulis 1974 em. Cavalier-Smith 2003** Class Centrohelea Kuhn 1926 stat. n. Cavalier-Smith 1993 entroplastiales; Centrohelina Hartmann 1913; Centroplasthelida Febvre-Chevalier 1984* Subphylum Haptophytina Cavalier-Smith 2015 (Haptophyta Hibberd 1976 sensu Ruggerio et al. 2015) ** Clade Rappemonada Kim et al. 2011 *** Class Rappephyceae Rappephyceae, or Rappemonads, are a small family of protists first described in 2011, of uncertain phylog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptista
Cryptista is a clade of algae-like eukaryotes. It is most likely related to Archaeplastida which includes plants and many algae, within the larger group Diaphoretickes. Although it has sometimes placed along with Haptista in the group Hacrobia, within the kingdom Chromista, most recent studies have found that Hacrobia is not a clade. For example, in 2016, a broad phylogenomic study found that cryptists fall within the group Archaeplastida, while haptophytes are closely related to the SAR supergroup. Taxonomy Based on studies done by Cavalier-Smith, Chao & Lewis 2015 *''Corbihelia'' ** Phylum Microheliellida Tedersoo 2017 [Endohelia Cavalier-Smith 2015] *** Class Endohelea Cavalier-Smith 2012 * Clade Cryptista s.s. ** Phylum Palpitophyta Tedersoo 2017 *** Class Palpitea Cavalier-Smith 2012 ** Clade Rollomonadia Cavalier-Smith 2013 stat. nov. *** Phylum Kathablepharidophyta Okamoto & Inouye 2005 [Leucocrypta Cavalier-Smith 2015] **** Class Leucocryptea Cavalier-Smith 2004 [Kathab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corbihelia
Corbihelia is a proposed phylum of eukaryotes. Classification Based on studies done by Cavalier-Smith, Chao & Lewis 2015 * Super Class Endohelia Cavalier-Smith 2015 ** Class Endohelea Cavalier-Smith 2012 *** Order Microhelida Cavalier-Smith 2011 **** Family Microheliellidae Cavalier-Smith 2011 ***** Genus ''Microheliella'' Cavalier-Smith & Chao 2012 *** Order Heliomonadida Cavalier-Smith 1993 emend. Cavalier-Smith 2012 **** Family Heliomorphidae Cavalier-Smith & Bass 2009 ***** Genus ''Heliomorpha'' Cavalier-Smith & Bass 2009 * Super Class Corbistoma Cavalier-Smith 2015 ** Class Picomonadea Seenivasan et al. 2013 [Biliphyta; Picobiliphytes; Picozoa Seenivasan et al. 2013] *** Order Picomonadida Seenivasan et al. 2013 **** Family Picomonadidae Seenivasan et al. 2013 ***** Genus ''Picomonas'' Seenivasan et al. 2013 ** Class Telonemea Cavalier-Smith 1993 (Telonemia Shalchian-Tabrizi 2006] *** Order Telonemida Cavalier-Smith 1993 **** Family Telonemidae Cavalier-Smith 1993 ***** Genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAR Supergroup
The SAR supergroup, also just SAR or Harosa, is a clade that includes stramenopiles (heterokonts), alveolates, and Rhizaria. The name is an acronym derived from the first letters of each of these clades; it has been alternatively spelled "RAS". The term "Harosa" (at the subkingdom level) has also been used. The SAR supergroup is a node-based taxon. Note that as a formal taxon, "Sar" has only its first letter capitalized, while the earlier abbreviation, SAR, retains all uppercase letters. Both names refer to the same group of organisms, unless further taxonomic revisions deem otherwise. Members of the SAR supergroup were once included under the separate supergroups Chromalveolata (Chromista and Alveolata) and Rhizaria, until phylogenetic studies confirmed that stramenopiles and alveolates diverged with Rhizaria. This apparently excluded haptophytes and cryptomonads, leading Okamoto ''et al.'' (2009) to propose the clade Hacrobia to accommodate them. Phylogeny Based on a compi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromista
Chromista is a biological kingdom consisting of single-celled and multicellular eukaryotic species that share similar features in their photosynthetic organelles (plastids). It includes all protists whose plastids contain chlorophyll ''c'', such as some algae, diatoms, oomycetes, and protozoans. It is probably a polyphyletic group whose members independently arose as a separate evolutionary group from the common ancestor of all eukaryotes. As it is assumed the last common ancestor already possessed chloroplasts of red algal origin, the non-photosynthetic forms evolved from ancestors able to perform photosynthesis. Their plastids are surrounded by four membranes, and are believed to have been acquired from some red algae. Chromista as a biological kingdom was created by British biologist Thomas Cavalier-Smith in 1981 to differentiate some protists from typical protozoans and plants. According to Cavalier-Smith, the kingdom originally included only algae, but his later analysis in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hacrobia
The cryptomonads-haptophytes assemblage is a proposed monophyletic grouping of unicellular eukaryotes that are not included in the SAR supergroup. Several alternative names have been used for the group, including Hacrobia (derived from "ha-" referring to Haptophyta, "-cr-" referring to cryptomonads, and "-bia" as a general suffix referring to life); CCTH (standing for Cryptophyta, Centrohelida, Telonemia and Haptophyta); and "Eukaryomonadae". , it is unclear whether this group is monophyletic or not; results of phylogenetic studies are "often dependent on the selection of taxa and gene data set". Two 2012 studies produced opposite results. Members In the past, heterokonts, haptophytes, and cryptomonads have sometimes been grouped together in a group known as chromists. Though the heterokonts are now split out, Cryptophyta and Haptophyta are considered in some studies to be closely related (and are sometimes simply referred to as the "Cryptophyta+Haptophyta" group). A 2009 pape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeplastida
The Archaeplastida (or kingdom Plantae ''sensu lato'' "in a broad sense"; pronounced /ɑːrkɪ'plastɪdə/) are a major group of eukaryotes, comprising the photoautotrophic red algae (Rhodophyta), green algae, land plants, and the minor group glaucophytes. It also includes the non-photosynthetic lineage Rhodelphidia, a predatorial (eukaryotrophic) flagellate that is sister to the Rhodophyta, and probably the microscopic picozoans. The Archaeplastida have chloroplasts that are surrounded by two membranes, suggesting that they were acquired directly through a single endosymbiosis event by feeding on a cyanobacterium. All other groups which have chloroplasts, besides the amoeboid genus ''Paulinella'', have chloroplasts surrounded by three or four membranes, suggesting they were acquired secondarily from red or green algae. Unlike red and green algae, glaucophytes have never been involved in secondary endosymbiosis events. The cells of the Archaeplastida typically lack centriol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
