Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           "neomura" Cavalier-Smith 1987
             Domain Eukaryota Chatton, 1925 - eukaryotes
               neokaryotes Cavalier-Smith 1993 - mitochondrial eukaryotes
                 neozoa Cavalier-Smith 1993
                   Superkingdom Corticata Lankester, 1878
                     Kingdom Plantae Haeckel (1866) - plants
                       Subkingdom Viridiplantae Caval.-Sm. (1981) - green plants
                         Infrakingdom Streptophyta C. Jeffrey (1967)
                           Superphylum Embryophyta
                             "polysporangiophytes"
                               Phylum Tracheophyta Sinnott ex Caval.-Sm. (1998) - vascular plants
                                 Subphylum Euphyllophytina
                                   Infraphylum "Radiatopses" Kenrick & Crane (1997)
                                     "lignophytes"
                                       Class Spermatopsida
                                         "core seed plants"
                                           Subclass Pinidae Cronquist, Takht. & Zimmerm. (1966)
                                             Order Pinalesᵀ Gorozh. (1904) - conifers
                                               Family Pinaceaeᵀ Spreng. ex F. Rudolphi (1830) - pine family
                                                 Subfamily Piceoideae
                                                   Genus Piceaᵀ A. Dietr. (1824)
                                                     Picea abies (L.) H. Karst. (1881) - Norway spruce
                                                     Picea alcoquiana (Veitch ex Lindl., 1861) Carrière (1867)
                                                     Picea asperata Mast. (1906)
                                                     Picea canadensis (P. Mill.) B.S.P.
                                                     Picea engelmannii (Parry) Engelm. - Columbian spruce
                                                     Picea glauca (Moench) Voss (1907) - white spruce
                                                     Picea jezoensis (Siebold & Zucc.) Carrière (1855) - Yeddo spruce
                                                     Picea marina
                                                     Picea morrisonicola Hayata (1908)
                                                     Picea omorika (Pancíc) Bolle
                                                     Picea orientalis (L.) Link
                                                     Picea pungens Engelm. (1879) - blue spruce
                                                     Picea rubens Sarg. (1898) - red spruce
                                                     Picea schrenkiana Fisch. & C.A.Mey. (1842)
                                                     Picea sitchensis (Bong.) Carrière (1855) - Sitka spruce
                                                     Picea smithiana (Wall.) Boiss. (1884)