Some remarks on the classification and differentiation of Moraceae

With the appearance in 1889 of Engler’s treatment of the Urticales in “Die natürlichen Pflanzenfamilien” there came a pause in the interesting development of the classification of this group, which was defined, albeit somewhat vaguely, by A.L. de Jussieu in 1789 in his “Genera Plantarum” as the order Urticeae. Since the 1830’s, many, including Gaudichaud, Trécul, Miquel, Bureau, Eichler, Baillon, and Bentham, have contributed to the establishment of the Engler system which until recently has been generally accepted. An important moment in this history was the appearance of Trécul’s treatment of the then most problematical group, the “family” Artocarpeae. Trécul (1847) considered the “families” which at that time were distinguished within the “class” Urticineae, viz Moreae, Urticeae, Ulmeae, Celtideae, and Cannabineae, as being very closely related to the Artocarpeae. Along with the Conocephaleae, split off from the Artocarpeae, we find these “families” as tribes of the “class” Urticaceae in the “Genera Plantarum” of Bentham and Hooker (1880) and as subfamilies or families in Engler: the subfamilies Moroideae, Artocarpoideae, Conocephaloideae, and Cannaboideae in the family Moraceae, the subfamilies Ulmoideae and Celtoideae in the family Ulmaceae, and finally the family Urticaceae. Since the end of the last century and until recently no revisions of any large groups of Moraceae and Urticaceae had appeared. But with the development of monographic taxonomic research the system has come out of its static situation, as can be seen from the study by Corner (1962). He proposed a new delimitation of the Moraceae and Urticaceae and another subdivision of the Moraceae sensu stricto.