Ka
Kadosactis Danielssen, 1890
- Kadosactis abyssicola (Koren & Danielssen, 1877)
- Kadosactis antarctica (Carlgren, 1928)
- Kadosactis rosea Danielssen, 1890
- Kadosactis spitsbergensis (Danielssen, 1890)
- Kadosactis sulcata Carlgren, 1934
Animalia → Cnidaria → Anthozoa → Actiniaria → Acontiaria → Kadosactinidae
- Kantiella
Ke
†Kenelasma Sytova 1979
- Kenelasma sibiricum Sytova 1979
Animalia → Cnidaria → Anthozoa → Rugosa
- Kephyes
- Keralica
Keratoisis Wright, 1869
- Keratoisis chuni (Kükenthal, 1915)
- Keratoisis flabellum (Nutting, 1908)
- Keratoisis flexibilis (Pourtalès, 1868)
- Keratoisis glaesa Grant, 1976
- Keratoisis gracilis (Thomson & Henderson, 1906)
- Keratoisis grandiflora Studer, 1878
- Keratoisis grandis (Nutting, 1908)
- Keratoisis grayi (Wright, 1869)
- Keratoisis hikurangiensis Grant, 1976
- Keratoisis japonica Studer, 1878
- Keratoisis macrospiculata (Kükenthal, 1915)
- Keratoisis magnifica Dueñas, Alderslade & Sánchez, 2014
- Keratoisis microspiculata Molander, 1929
- Keratoisis palmae (Wright & Studer, 1889)
- Keratoisis paucispinosa (Wright & Studer, 1889)
- Keratoisis peara Dueñas, Alderslade & Sánchez, 2014
- Keratoisis philippinensis (Wright & Studer, 1889)
- Keratoisis profunda (Wright, 1885)
- Keratoisis projecta Grant, 1976
- Keratoisis siemensii Studer, 1878
- Keratoisis squarrosa (Kükenthal, 1915)
- Keratoisis tangentis Grant, 1976
- Keratoisis wrighti (Nutting, 1910)
- Keratoisis zelandica Grant, 1976
Cnidaria → Anthozoa → Alcyonacea → Calcaxonia → Isididae
- Keroeides
- Keroeididae
Ki
†Kiaerites Stasinska, 1967
- †Kiaerites norvegicus Stasinska, 1967 [1]
Cnidaria → Anthozoa → Tabulata → Sarcinulida → Theciidae
†Kiaerolites Bondarenko, 1977
Cnidaria → Anthozoa → Heliolitida → Proporicae → Proheliolitidae
- Kinetocodium
- Kionotrochus
- Kirchenpaueria
- Kirchenpaueriidae
- Kishinouyea
- Kishinouyeidae
Kl
- Klyxum
Kn
- Knopia
Ko
- Koellikerina
- Kophobelemnidae
- Kophobelemnon
- Korsaranthus
Kr
- Krampella
Kt
Ktenosquamisis Alderslade, 1998
- Ktenosquamisis bicamella Alderslade, 1998
Cnidaria → Anthozoa → Alcyonacea → Calcaxonia → Isididae
Ky
- Kyopoda
- Kyopodidae