肢口綱

肢口綱（學名：Merostomata）是一綱水生的螯肢亞門，其下包括了鱟。現存的肢口綱只剩一個劍尾目4個物種，分別為中華鱟、南方鱟、美洲鱟、圓尾鱟，但有大量主要屬於古生代的化石物種。 肢口綱是螯肢亞門之中唯一擁有複眼的，而蛛形綱則失去了節肢動物祖先發展完好的側前複眼。 史前的板足鱟綱（Eurypterida）曾被归类為本綱之下的一個亞綱，但後來被許多學者認為更接近蛛形綱，因而將板足鱟綱分出去獨立成為一綱，與蛛形綱另組成硬器類（Sclerophorata）或Cryptopneustida。 肢口綱的學名“Merostomata”是從希臘文 μηρός（meros，“大腿”）和στόμα（stoma，“口”）組合而來，因本綱動物的口器附近擁有附肢而得名。 本纲包括以下目： 剑尾目 Xiphosurida 目的地位未定的科： Adelophthalmidae Brachyopterellidae Bunodidae Carcinosomatidae Chasmataspidae Cyrtoctenidae Diploaspididae Dolichopteridae Drepanopteridae Erieopteridae Euproopidae Eurypteridae Hardieopteridae Heteroaspididae Heterolimulidae 希氏鲎科 Hibbertopteridae Hughmilleriidae Jaekelopteridae Kokomopteridae Lanarkopteridae Laurieopteridae Liomesaspidae Liomesaspididae Megalograptidae Mixopteridae Moravuridae Moselopteridae Mycteropidae Parastylonuridae Pterygotidae Rhenopteridae Slimoniidae Stylonuridae Weinberginidae Woodwardopteridae 目和科的地位未定的属： Aglaspidichnus Radwanksi & Roniewicz, 1967 Anderella Moore, McKenzie & Lieberman, 2007 Anthraconectes Meek & Worthen, 1868 Baltoeurypterus Størmer, 1973 Beaumontia David, 1928 Belinuropsis Matthew, 1909 Bembicosoma Laurie, 1900 Bembycosoma Laurie, 1900 Bifarius Tasch, 1961 Borchgrevinkium Novojilov, 1958 Brachopterella Bunaia Clarke, 1920 Camanchia Moore, Briggs, Braddy & Shultz, 2011 Caragassia Vologdin, 1965 Carbonolimulus Hong, 1985 Chasmataspis Caster & Brooks, 1956 Curviramus Ruedemann, 1935 Cyamocephalus Currie, 1927 Dibasterium Briggs, Siveter, Siveter, Sutton, Garwood & Legg, 2012 Dibasterium durgae Dickinsonia Tasch, 1963 Dipeltis Packard, 1885 Dvulikiaspis Marshall, Lamsdell, Shpinev & Braddy, 2013 Elleria Raymond, 1944 Elmocephalus Tasch, 1964 Eocarcinsoma Caster & Kjellesvig-Waering, 1964 Eurypterella Matthew, 1889 Eusarcus Grote & Pitt, 1875 Exoculatus Pirozhnikov, 1966 Gdowia Yanishevsky, 1950 Glaucodes Pruvost, 1924 Grossopterus Størmer, 1935 Habcyne Meyer, 1844 Hastimima Seward, 1909 Heteroaspis Stormer, 1972 侯氏翅鲎属 Holmipterus Kjellesvig-Waering, 1979 Hypatocephala Tasch, 1961 Ikeyia Vologdin, 1965 Iyaia Vologdin, 1965 Kasibelinurus Pickett, 1993 Kioeria Størmer, 1933 Lagrandella Eldredge, 1974 Laurieopterus Legrandella Eldredge, 1974 Limulicubichnus Miller, 1982 Limulites Krueger, 1823 Mazonipterus Kjellesvig-Waering, 1963 Nahlyostaspis Marshall, Lamsdell, Shpinev & Braddy, 2013 Neobelinuropsis Eller, 1938 Neolimulus Woodward, 1868 Onychopterella Størmer, 1951 Orcanopterus Stott, Tetlie, Braddy, Nowlan, Glasser & Devereux, 2005 Palatinaspis Malz & Poschmann, 1993 Paraeurypterus Lamsdell, Hosgör & Selden, 2013 Parahughmillera Kjellesvig-Waering, 1961 Parka Fleming, 1864 Pasternakevia Selden & Drygant, 1987 Pentlandopterus Lamsdell, Hosgör & Selden, 2013 Permolimulinella Tasch, 1963 Pincombella Chapman, 1932 Polystomurum Novozhilov, 1958 Psammonlimulus Pseudoniscus Nieszkowski, 1859 Pseudostylonurus Xie & Xie, 1989 Raaschichnus Hesselbo, 1988 Rutroclypeus Withers, 1933 Sanctacarus Selenichnites Romano & Whyte, 1990 Skrytyaspis Marshall, Lamsdell, Shpinev & Braddy, 2013 Steropis Bailey, 1858 Strongylocephalus Tasch, 1961 Stylonarus Page, 1856 Stylonuroides Kjellesvig-Waering, 1966 Syntomopterella Tetlie, 2007 Syntomopterus Kjellesvig-Waering, 1961 Thurandina Stormer, 1974 Tremaglaspis Fortey & Rushton, 2003 Truncatiramus Kjellesvig-Waering, 1961 Willwerathia Stormer, 1969 Boudreaux H. B. Arthropod phylogeny with special reference to insects. New York, Chichester, Brisbane, Toronto: John Willey & sons. 1979: 320 pp.  Weygoldt, P. & Paulus, H.F. Untersuchungen zur Morphologie, Taxonomie und Phylogenie der Chelicerata. Zeitschrift für zoologische Systematik und Evolutionsforschung. 1979, 17: 85–116, 177–200.  Merostomata. GBIF. [2023-03-23]. （原始内容存档于2022-08-19）.  Eric Gershon, Dibasterium durgae • Silurian horseshoe crab illuminates the evolution of arthropod limbs 石川良輔編『節足動物の多様性と系統』,(2008),バイオディバーシティ・シリーズ6(裳華房) Horseshoe Crabs (Class Merostomata) （页面存档备份，存于互联网档案馆）