Lineus is a genus of nemertine worms, including the bootlace worm, arguably the longest animal alive. Lineus contains the following species: Lineus acutifrons Southern, 1913 Lineus albifrons Coe, 1934 Lineus albocinctus Verrill, 1900 Lineus albonasus Verrill, 1900 Lineus alborostratus Takakura, 1898 Lineus albus Lineus alienus Bürger, 1895 Lineus anellatus Lineus angulosus Korotkevich, 1978 Lineus arenicola (Verrill, 1873) Lineus atradentis Korotkevich, 1978 Lineus atrocaeruleus (Schmarda, 1859) Lineus auripunctatus (Grube, 1855) Lineus aurostriatus (Bürger, 1890) Lineus australis Lineus autrani Joubin, 1905 Lineus bergendali Senz, 1996 Lineus bilineatus (Renier, 1804) Lineus binigrilinearis Gibson, 1990 Lineus bioculatus Sundberg & Gibson, 1995 Lineus bipunctatus Takakura, 1898 Lineus bonaerensis Moretto, 1971 Lineus boutani (Joubin, 1893) Lineus callaris Korotkevich, 1978 Lineus cancelli Iwata, 1954 Lineus capensis Wheeler, 1940 Lineus caputornatus Takakura, 1898 Lineus cinereus Punnett, 1903 Lineus cingulatus (Stimpson, 1855) Lineus coccinus Bürger, 1892 Lineus collaris (Schmarda, 1859) Lineus coloratus (Bürger, 1890) Lineus copus Corrêa, 1958 Lineus crosslandi Punnett & Cooper, 1909 Lineus desori Schmidt, 1946 Lineus dohrnii (Hubrecht, 1879) Lineus fischeri Senz, 1997 Lineus flammeus Lineus flavescens Coe, 1904 Lineus frauenfeldi Senz, 1997 Lineus fulvus Iwata, 1954 Lineus fuscoviridis Takakura, 1898 Lineus galbanus (Bürger, 1890) Lineus gesserensis (O. F. Müller, 1774) Lineus gilbus Bürger, 1892 Lineus gilviceps Sundberg & Gibson, 1995 Lineus glaucus (Bürger, 1890) Lineus grubei (Hubrecht, 1879) Lineus hancocki Punnett & Cooper, 1909 Lineus hiatti Coe, 1947 Lineus hubrechti (Langerhans, 1880) Lineus indicus Punnett & Cooper, 1909 Lineus insignis Senz, 1993 Lineus iota Joubin, 1902 Lineus islandicus Friedrich, 1958 Lineus kennelii Bürger, 1892 Lineus kolaensis Ushakov, 1928 Lineus kristinebergensis Gering, 1912 Lineus lacticapitatus Wheeler, 1940 Lineus lancearius Korotkevich, 1978 Lineus levinensis Korotkevich, 1978 Lineus linearis Montagu, 1808 Lineus lobianki Bürger, 1892 Lineus longifissus sensu Takakura, 1898 Lineus longifissus sensu Iwata, 1952 Lineus longissimus (Gunnerus, 1770) Lineus marisalbi Ushakov, 1926 Lineus mascarensis Punnett & Cooper, 1909 Lineus mcintoshii (Langerhans, 1880) Lineus molochinus Bürger, 1892 Lineus monolineatus Staub, 1900 Lineus nigrobrunneus Bergendal, 1903 Lineus nigrofuscus (Stimpson, 1857) Lineus nigrostriatus Iwata, 1954 Lineus nipponensis Senz, 2001 Lineus obscurus Lineus oculatus Lineus orientalis Punnett & Cooper, 1901 Lineus ornatus Wheeler, 1940 Lineus pallidus Verrill, 1879 Lineus parvulus Bürger, 1892 Lineus patulus Isler, 1900 Lineus pictifrons Coe, 1904 Lineus picus Corrêa, 1958 Lineus polyophthalmus (Schmarda, 1859) Lineus pseudoruber (Friedrich, 1935) Lineus psittacinus (Bürger, 1890) Lineus quadratus Korotkevich, 1978 Lineus ramosus Isler, 1900 Lineus rovinjensis Senz, 1995 Lineus ruber (Müller, 1774) Lineus rubescens Coe, 1904 Lineus rufocaudatus Bürger, 1892 Lineus