The mucron is located at the anterior (apical) end of the cell and comprises theconoid,rhoptries, apicalpolar ring(s), and a large foodvacuole (also called mucronal vacuole) having an outlet opening—acytostome. It is used to attach and feed from the host's cell.[4][5][6]
Theepimerites of some aseptateeugregarines superficially (at the light microscopic level) resemble mucron and are usually called in the same way.[1][3][2] This widespread misunderstanding originated from the conventional definition first proposed by Levine in 1971: "[the mucron is] an attachment organelle of aseptate gregarines. It is similar to an epimerite, but is not set off from the rest of the gregarine body by what appears under the light microscope to be a septum."[7] Thus, it may be equally applied to archigregarines and aseptate eugregarines as both they are aseptate. Note that the genuine epimerites are usually not separated by septa from the rest of the cell,[8][9] so this definition is misleading.[2]
^abcPerkins FO, Barta JR, Clopton RE, Peirce MA, Upton SJ (2000). "Phylum Apicomplexa". In Lee JJ, Leedale GF, Bradbury P (eds.).An Illustrated guide to the Protozoa: organisms traditionally referred to as protozoa, or newly discovered groups. Vol. 1 (2nd ed.). Society of Protozoologists. pp. 190–369.ISBN1891276220.OCLC704052757.
^abcSimdyanov TG, Guillou L, Diakin AY, Mikhailov KV, Schrével J, Aleoshin VV. (2017) A new view on the morphology and phylogeny of eugregarines suggested by the evidence from the gregarineAncora sagittata (Leuckart, 1860) Labbé, 1899 (Apicomplexa: Eugregarinida)PeerJ 5:e3354doi:10.7717/peerj.3354
^abAdl SM, Simpson AG, Lane CE, Lukeš J, Bass D, Bowser SS, Brown M, Burki F, Dunthorn M, Hampl V, Heiss A, Hoppenrath M, Lara E, leGall L, Lynn DH, McManus H, Mitchell EAD, Mozley-Stanridge SE, Parfrey LW, Pawlowski J, Rueckert S, Shadwick L, Schoch C, Smirnov A, Spiegel FW. (2012) The revised classification of eukaryotes.Journal of Eukaryotic Microbiology 59:429-514.doi:10.1111/j.1550-7408.2012.00644.x
^Schrével J. (1971) Observations biologiques et ultrastructurales sur les Selenidiidae et leurs conséquences sur la systématique des Grégarinomorphes.Journal of Protozoology 18:448–479.doi:10.1111/j.1550-7408.1971.tb03355.x
^Schrével J, Valigurová A, Prensier G, Chambouvet A, Florent I, Guillou L. (2016) Ultrastructure ofSelenidium pendula, the type species of archigregarines, and phylogenetic relations to other marine Apicomplexa.Protist 167:339-368.doi:10.1016/j.protis.2016.06.001
^Simdyanov TG, Kuvardina ON. (2007) Fine structure and putative feeding mechanism of the archigregarineSelenidium orientale (Apicomplexa: Gregarinomorpha).European Journal of Protistology 43:17-25.doi:10.1016/j.ejop.2006.09.003
^Levine ND. (1971) Uniform terminology for the protozoan subphylum Apicomplexa.Journal of Protozoology 18:352-355.doi:10.1111/j.1550-7408.1971.tb03330.x
^Grassé, P.P.; Caullery, M.C. (1953).Traité de zoologie: anatomie, systématique, biologie. Tome I, Fasc. II, Protozaires, rhizopodes, Actinopodes, Sporozoaires, Cnidosporidies. Paris: Masson et Cie.OCLC642231286.
