Kudoa
Kudoa is a genus of Myxozoa and the only genus recognized within the monotypic family Kudoidae. There are approximately 100 species of Kudoa all of which parasitize on marine and estuarine fish. Kudoa are most commonly known and studied for the negative effects the genus has on commercial fishing and aquaculture industries.
Description
The genus Kudoa is identified by the possession of four or more shell valves composed of a fragile membrane and arranged in a quadrate or stellate pattern. The maximum number of shell valves in any described Kudoa species is 13. Each of these valves has a polar capsule. The genus Kudoa was originally part of the genus Chloromyxum because of the distribution of their polar capsules, however, it was later determined to be a separate genus. Each Kudoa has two sporoplasm cells, one enclosed by the other. Most Kudoa are histozoic parasites, with a few species being described as coelzoic. Some taxonomists question whether these coelzoic organisms belong to a separate genus. There are approximately 100 described species of Kudoa which can be found in the Atlantic, Pacific, and Indian oceans.Species
The following species are recognized in the genus Kudoa:Kudoa aburakarei Li, Inoue, Tanaka, Zhang & Sato, 2020Kudoa acentrogobia Li, Inoue, Tanaka, Zhang & Sato, 2020Kudoa aequidens Casal, Matos, Matos & Azevedo, 2008Kudoa ajurutellus Araújo-Neto, Cardim, Da Silva, Hamoy, Matos & Abrunhosa, 2020Kudoa akihitoi Kasai, Setsuda & Sato, 2017Kudoa alliaria Kovaleva, Shulman & Yakolev, 1979Kudoa amamiensis Egusa & Nakajima, 1978Kudoa amazonica Velasco, Sindeaux Neto, Videira, de Cássia Silva do Nascimento, Gonçalves & Matos, 2019Kudoa anatolica Özer, Okkay, Gürkanlı, Çiftçi & Yurakhno, 2018Kudoa azevedoi Mansour, Thabet, Chourabi, Harrath, Gtari, Omar & Hassine, 2013Kudoa azoni Aseeva, 2004Kudoa barracudai Abdel-Baki, Al-Quraishy, Omar & Mansour, 2016Kudoa bengalensis Sarkar & Mazumder, 1983Kudoa boopsi Kpatcha, Diebakate, Faye & Toguebaye, 1999Kudoa bora Fujita, 1930Kudoa borimiri Yurakhno, Slynko, Chinh, Ha & Whipps, 2022Kudoa branchiata Joy, 1972Kudoa camarguensis Pampoulie, Marques, Crivelli & Boucherau, 1999Kudoa carcharhini Gleeson, Bennett & Adlard, 2010Kudoa cascasia Sarkar & Chaudry, 1996Kudoa caudata Kovaleva & Gaevskaya, 1983Kudoa cerebralis Paperna & Zwerner, 1974Kudoa chaetodoni Burger, Cribb & Adlard, 2007Kudoa cheilodipteri Heiniger, Cribb & Adlard, 2013Kudoa chilkaensis Tripathi, 1951Kudoa ciliatae Lom, Rohde & Dyková, 1992Kudoa clupeidae Hahn, 1917Kudoa cookii Heiniger, Cribb & Adlard, 2013Kudoa corniculata Li, Inoue, Zhang & Sato, 2022Kudoa crenimugilis Abdel-Baki, Abdel-Haleem, Al-Quraishy, Azevedo & Mansour, 2018Kudoa cruciformum Matsumoto, 1954Kudoa crumena Iversen & van Meter, 1967Kudoa cynoglossi Obiekezie & Lick, 1994Kudoa dianae Dyková, Fajer & Fiala, 2002Kudoa dicentrarchi Sitjà-Bobadilla & Alvarez-Pellitero, 1992Kudoa empressmichikoae Kasai, Setsuda & Sato, 2017Kudoa encrasicoli Iglesias, Rangel, Fernández-Vázquez, Santos & García-Estévez, 2022Kudoa eugerres Casal, Soares, Rocha, Silva, Santos, Nascimento, Oliveira & Azevedo, 2019Kudoa fujitai Li, Inoue, Zhang & Sato, 2020Kudoa funduli Hahn, 1915Kudoa grammatorcyni Adlard, Bryant, Whipps & Kent, 2005Kudoa guangdongensis Li, Inoue, Tanaka, Zhang & Sato, 2020Kudoa gunterae Burger & Adlard, 2009Kudoa haridasae Sarkar & Ghosh, 1991Kudoa hemiscylli Gleeson, Bennett & Adlard, 2010Kudoa hexapunctata Yokoyama, Suzuki & Shirakashi, 2014Kudoa hirsuta Li, Inoue, Zhang & Sato, 2022Kudoa histolytica Pérard, 1928Kudoa hypoepicardialis Blaylock, Bullard & Whipps, 2004Kudoa igami Shirakashi, Yamane, Ishitani, Yanagida & Yokoyama, 2014Kudoa igori Yurakhno, Slynko, Chinh, Ha & Whipps, 2022Kudoa iidae Li, Inoue, Tanaka, Zhang & Sato, 2020Kudoa inornata Dykova, de Buron, Fiala, Roumillat, 2009Kudoa insolita Shulman & Kovalijova, 1979Kudoa intestinalis Maeno, Magasawa & Sorimachi, 1993Kudoa islandica Kristmundsson & Freeman, 2014Kudoa iwatai Egusa & Shiomitsu, 1983Kudoa javaensis Yunus, Yustinasari, Natalia, Ghosh, Sakuma, Inoue & Sato, 2021Kudoa kabatai Shulman & Kovalijova, 1979Kudoa kenti Burger & Adlard, 2009Kudoa konishiae Sakai, Kato, Sakaguchi, Setsuda & Sato, 2018Kudoa lateolabracis Yokoyama, Whipps, Kent, Mizuno & Kawakami, 2004Kudoa leiostomi Dyková, Lom & Overstreet, 1994Kudoa lemniscati Miller & Adlard, 2012Kudoa leptacanthae Heiniger & Adlard, 2012Kudoa lethrini Burger, Cribb & Adlard, 2007Kudoa longichorda Inoue, Kasai, Argamjav & Sato, 2022Kudoa lunata Lom, Dyková & Lhotákova, 1983Kudoa lutjanus Wang, Huang, Tsai, Cheng, Tsai, Chen, Chen, Chiu, Liaw, Chang & Chen, 2005Kudoa megacapsula Yokoyama & Itoh, 2005Kudoa miniauriculata Whitaker, Kent & Sakanari, 1996Kudoa minithyrsites Whipps, Adlard, Bryant, Lester, Findlay & Kent, 2003Kudoa mirabilis Naidenova & Gaevskaya, 1991Kudoa monodactyli Gunter, Cribb, Whipps & Adlard, 2006Kudoa muscularis Cheung, Nigrellu & Ruggieri, 1983Kudoa musculoliquefaciens Matsumoto & Arai, 1954Kudoa neothunni Arai & Matsumoto, 1953Kudoa neurophila Grossel, Dyková, Handlinger & Munday, 2003Kudoa niluferi Özer, Okkay, Gürkanlı, Çiftçi & Yurakhno, 2018Kudoa nova Naidenova, 1975Kudoa obicularis Azevedo, Rocha, Matos, Oliveira, Matos, Al-Quraishy & Casal, 2015Kudoa ocellatus Da Silva, Da Silva, Lima, Matos, De Carvalho Sanches, Matos & Hamoy, 2022Kudoa ogawai Yokoyama, Yanagida & Shirakashi, 2012Kudoa ovivora Swearer & Robertson, 1999Kudoa pagrusi Al Quraishy, Koura, Abdel-Baki, Bashtar, El Deed, Al Rasheid & Abdel Ghaffar, 2008Kudoa paniformis Kabata & Whitaker, 1981Kudoa paralichtys Cho & Kim, 2003Kudoa paraquadricornis Burger & Adlard, 2009Kudoa parathyrsites Kasai, Li, Mafie & Sato, 2016Kudoa parvibulvosa Li, Inoue, Zhang & Sato, 2022Kudoa pericardialis Nakajima & Egusa, 1978Kudoa permulticapsula Whipps, Adlard, Bryant & Kent, 2003Kudoa peruvianus Mateo Salas, 1972Kudoa pleurogrammi Kasai, Li, Mafie & Sato, 2016Kudoa prunusi Meng, Yokoyama, Shirakashi, Grabner, Ogawa, Ishimaru, Sawada & Murata, 2011Kudoa quadratum Thélohan, 1895Kudoa quadricornis Whipps, Adlard, Bryant & Kent, 2003Kudoa quraishii Mansour, Harrath, Abd-Elkader, Alwasel, Abdel-Baki & Al Omar, 2014Kudoa ramsayi Kalavati, Brickle & MacKenzie, 2000Kudoa rayformis Shin, Shirakashi, Hamano, Kato, Lasso & Yokoyama, 2016Kudoa rosenbuschi Gelormini, 1966Kudoa rousseauxii Velasco, Eduard, Neto, Dias, Matos & Gonçalves, 2022Kudoa saudiensis Mansour, Harrath, Abdel-Baki, Alwasel, Al-Quraishy & Al Omar, 2015Kudoa schulmani Naidenova & Zaika, 1970Kudoa sciaenae Teran, Llicán & Lugue, 1990Kudoa scomberi Li, Sato, Tanaka, Ohnishi, Kamata & Sugita-Konishi, 2013Kudoa scomberomori Adlard, Bryant, Whipps & Kent, 2005Kudoa sebastea Aseeva, 2004Kudoa septempunctata Matsukane, Sato, Tanaka, Kamata & Sugita-Konishi, 2010Kudoa shiomitsui Egusa & Shiomitsu, 1983Kudoa shkae Dyková, Lom & Overstreet, 1994Kudoa sphyraeni Narasimhamurti & Kalavati, 1979Kudoa stellula Yurakhno, 1991Kudoa surabayaensis Yunus, Yustinasari, Natalia, Ghosh, Sakuma, Inoue & Sato, 2021Kudoa tachysurae Sarkar & Mazumder, 1983Kudoa tetraspora Narasimhamurti & Kalavati, 1979Kudoa thalassomi Adlard, Bryant, Whipps & Kent, 2005Kudoa thunni Matsukane, Sato, Tanaka, Kamata & Sugita-Konishi, 2011Kudoa thyrsites Gilchrist, 1924Kudoa trachuri Matsukane, Sato, Tanaka, Kamata & Sugita-Konishi, 2011Kudoa trifolia Holzer, Blasco-Costa, Sarabeev, Ovcharenko & Balbuena, 2006Kudoa unicapsula Yurakhno, Ovcharenko, Holzer, Sarabeev & Balbuena, 2007Kudoa viseuensis Monteiro, Da Silva, Hamoy, Sanches & Matos, 2019Kudoa whippsi Burger & Adlard, 2009Kudoa yasai Cardim, Araújo-Neto, da Silva, Hamoy, Matos & Abrunhosa, 2020Kudoa yasunagai Hsieh & Chen, 1984Development
In Myxozoan development, the Myxosporean life-stage develops inside a fish host, while the Actinosporean life-stage develops in an annelid host. Fully-developed Myxospores are consumed by annelids and reproduce asexually via schzogony in the gut epithelium of worms. Gametes are formed in the gut of the worm and these gametes fuse together to create eight zygotes. The zygotes become spores with three valves, 3 polar capsules, and a sporoplasm that are released in the worm's feces and attach to the surface of a fish host. Once attached to the fish, the gamete injects the sporoplasm cell into the fish. The sporoplast divides forming a fully-developed Myxosporean.Diet
Kudoa parasitize on marine and estuarine fish. Kudoa typically feed on the skeletal muscle tissue, although some may feed on other parts of the body such as the central nervous system, heart, intestines, ovaries, or gills. Most Kudoa are histozoic parasites, however, a few species are coelozoic. The genus Kudoa attack a wide range of hosts, however, individual species only feed on specific hosts. Kudoa feed via pinocytosis across the host-parasite membrane. One species of Kudoa, K. thyrsites, are distributed worldwide and are believed to have been reported in over 20 different species of fish but it is possible that the species described as K. thyrsites is actually multiple different species.Implications for the fishing industry
Kudoa are most well known for the economic loss they cause for the commercial fishing and aquaculture industries. When Kudoa attach to hosts, they leave unsightly cysts that lower the price fish can be sold for at market. Kudoa also release proteolytic enzymes that degenerate muscle in fish to aid in their own growth and development, further decreasing the fish's value. Some species in the genus Kudoa with the most notable effects of the commercial fishing and aquaculture industries are: K. musculoliquefaciens in Broadbill Swordfish, K. thyrsites in Atlantic Salmon, K. clupeidae in Atlantic Herring, K. septempunctata in Olive Flounder, K. thunni in Yellowfin Tuna and K. paniformis in Pacific Hake.Some studies have found evidence to suggest that some species of Kudoa are linked to food-borne illness in humans.