From phylum to genus - comments


The Phoronida have been assigned to various phyla of the animal kingdom and classified at several levels of importance. Several of these assignments were made by non-specialists of this zoological group, like Dalla Torre (1889), Poche (1903, 1908), several Soviet authors in the 2nd half of the last century, and Alonso-Zarazaga (2005). These authors applied the International Code of Zoological Nomenclature (ICZN*) in a strict, almost fundamentalist way, for they were unaware that the Phoronida represent one of the exceptions to this Code and that "no code is perfect. None will please everyone. Indeed, it is unlikely that any code would be completely satisfactory to any individual "(ICZN, 2000, p. XVIII). As written in the Preamble of the 4th edition of the ICZN (2000, p. 2 & 128), “the objects of the Code are to promote stability and universality in the scientific names of animals and to ensure that the name of each taxon is unique and distinct” - “L'objet du Code est de promouvoir la stabilité et l'universalité des noms scientifiques des animaux, et de faire en sorte que le nom de chaque taxon soit unique et distinct”, that is and has been the basis on which all specialists on the group have developed the systematics of the Phoronida for over 150 years. Those non-specialists did not delve into the taxonomy, the biology and the history of the Phoronida, all basic to an understanding of this unique group.

A few words about their history: Selys-Lonchamps (1907) provided an excellent history of the vicissitudes in the classification of the Phoronida; now, all the specialists (see Roule, Cori, Silén, Hyman, Zimmer, Emig) have agreed on a discrete nomenclature for the larva Actinotrocha and for the adult Phoronis, This proposal was submitted "officiously" by Silén (1952) to the International Commission on Zoological Nomenclature, who accepted it. There is no reason to doubt either the validity of the request to the Commission or of its acceptance. Furthermore, several articles and recommendations of the Code (particularly art. 23,2 and art. 23.9.2) are explicit enough to support and maintain the currently accepted systematics and taxonomy of the Phoronida, used by all, in all the scientific work. An attempt to apply the law of priority by using the larval name would require the creation of a new generic name for the species-group ovalis - hippocrepia ( types-species of Phoronis) - ijimai - australis and lead to difficulties and confusions in the assignments of the species-group muelleri - psammophila - pallida; the genus Phoronopsis would not be seriously affected (see the drawing), and in the future nobody would be able to distinct between what is adult form and what is larval one.

In the hierarchy of the Phoronida now accepted, no family has been expressly described and no diagnosis for it is available. The increase of databases regarding biodiversity tends towards an alteration in classification, because technically the field Family must be filled. Consequently the tendency is to use the designation Phoronidae, which has no validity. The proposal of a revision in order to satisfy the above citation from the Preamble of the ICZN, that is interpreted as requiring the preservation of the hierarchic succession species > genus > class-or-phylum is needed to avoid imbroglio in a group composed of only 10 valid species !

Translated and modified from Emig C. C., Roldán C. & J. M. Viéitez, 2005. Nota de los autores. In: Filo Phoronida. Fauna Ibérica,
vol. 27. Museo de Ciencias Naturales, CSIC Madrid, p. 54-56.

Best thanks to Nestor J. Sander (USA) for the language improvement and comments.

* International Commission on Zoological Nomenclature, 2000. International code of zoological nomenclature, 4e ed., p. 1-126 (and p. I-XXIX)
* Commission Internationale de Nomenclature Zoologique, 2000. Code International de nomenclature zoologique, 4e ed., p. 127-263.