JARS v64n4 - Rhododendron section Schistanthe, the Scientific Name for Vireya Rhododendrons (Ericaceae)

Rhododendron section Schistanthe, the Scientific Name for Vireya Rhododendrons (Ericaceae)
Lyn A. Craven
Australian National Herbarium
Canberra, ACT Australia

Frédéric Danet
Herbier du Jardin botanique de Lyon
Lyon, France

Jef Veldkamp
National Herbarium of the Netherlands
Leiden, The Netherlands

Loretta A. Goetsch and Benjamin D. Hall
Departments of Biology and Genome Sciences
University of Washington
Seattle WA, U.S.A.

Early on in the developing discipline of systematic botany, botanists realised that a plant should have only a single accepted name. The confusion that would ensue if each botanist adopted a different name for the same plant was obvious. The first international rules for botanical nomenclature were elaborated by Alphonse de Candolle and adopted during the International Congress of Botany held in Paris in 1867. Gradually, this code of practice, the International Code of Botanical Nomenclature (ICBN), became established throughout the world so that standardized rules would apply to the naming of plants. Not only did this code cover the formation and publication of the names of new taxa of plants; it also covered what to do when it was realised that two or more taxa represented the same taxon and a single name had to be selected for that taxon. The code applies to plant and fungal taxa at all ranks, families, genera, subgenera, section, subsections, species and so on. Regularly updated, the version of the code presently in force is known as the Vienna Code. This was published in 2006 (McNeill et al. 2006) and is available on the internet. The ICBN has the principle of priority of publication date as one of its major features. Another is that no name has priority outside its own rank.

In 1917, the German botanist Friedrich Richard Rudolf Schlechter (1872-1925), more famous for his work on orchids then perhaps any other group of plants, published five new sections for Rhododendron species from New Guinea (Schlechter 1917, 1918). The five sections are: Hadranthe Schltr., Hapalanthe Schltr., sect. Linnaeopsis Schltr., Schistanthe Schltr. and Zygomorphanthe Schltr. Twelve years later, Herbert Faulkner Copeland (1902–1968), who was working on Rhododendron from the Philippines, published the name R. sect. Vireya (C.B. Clarke) H.F. Copel. for a group of species, typifying the name with the species R. javanicum (Blume) Benn. (Copeland 1929). Presumably Copeland, if indeed he was aware of Schlechter's publication, believed that the New Guinea species had no relationship with the Rhododendron flora of the Philippines and islands to the west, such as Java and Borneo. Unfortunately, Hermann Otto Sleumer (1906-1993) who established the basis of contemporary Rhododendron classification in his publication Ein System der Gattung Rhododendron L . (Sleumer 1949), did not take up one of Schlechter's five sectional names for the part of the genus that includes all the plants known commonly as vireya rhododendrons. Instead, Sleumer used the name sect. Vireya. Possibly Sleumer did this in the belief that the Copeland name, being based on Blume's genus Vireya (Blume 1826), had a greater moral claim to priority than did the Schlechter names published in 1917. Sleumer also used sect. Vireya for the section in his influential treatment of Rhododendron for Flora Malesiana (Sleumer 1966).

Remarkably, no botanist subsequently has recognised that the name Vireya should not be used for the section when it is circumscribed to include all the vireya rhododendrons. Argent (2006) included all of Schlechter's names in subordinate synonymy, even though he published new names at sectional rank for taxa that already had a validly published name. As the name sect. Vireya is so well known, it would be advantageous if it could be conserved against the Schlechter names. The ICBN does have provisions for the conservation of well-established names of genera and species, but not for the names of ranks between these, such as section. The type of Blume's genus Vireya is R. javanicum and in Schlechter's key to his sections (Schlechter 1917) this species keys to sect. Schistanthe . [Schlechter's paper was spread across two issues of the journal ( Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie ) and unfortunately across two years, 1917 and 1918. His sectional names are published in the part published in 1917 although several of them were more fully detailed in the 1918 part of his paper.]

In keeping to the spirit of having the nomenclatural concept of the group associated with R. javanicum , we have therefore taken up Schistanthe as the correct name for vireya rhododendrons. In the formal synonymy given below, only published names of the rank of section are included. A full synonymy, dealing with other nomenclature relevant to vireyas, will be given in a paper presently being prepared in which the classification of the section will be revised in the light of recent molecular studies.

Rhododendron sect. Schistanthe Schltr., Bot. Jahrb. Syst. 55: 140. 1917. Lectotype: R. hansemannii Warb. (" hansemanni ", designated by Sleumer (1960: 176). (This species is now included in R. macgregoriae F. Muell.)

sect. Albovireya (Sleumer) Argent, Rhododendrons of subgenus Vireya . 22. 2006. Type: R. album Blume

sect. Discovireya (Sleumer) Argent, Rhododendrons of subgenus Vireya . 21. 2006. Type: R. retusum (Blume) Benn. ( Vireya retusa Blume)

sect. Euvireya (H.F. Copel.) Argent, Rhododendrons of subgenus Vireya . 24. 2006, nom. superfl . Type: R. javanicum (Blume) Benn. ( Vireya javanica Blume)

sect. Hadranthe Schltr., Bot. Jahrb. Syst. 55: 140. 1917. Lectotype: R. hellwigii Warb., designated by Sleumer (1960: 71)

sect. Hapalanthe Schltr., Bot. Jahrb. Syst. 55: 140. 1917. Lectotype: R. zoelleri Warb., designated by Sleumer (1960: 176)

sect. Linnaeopsis Schltr., Bot. Jahrb. Syst. 55: 140, 145. 1917. Type: R. linnaeoides Schltr., see Sleumer (1960: 134). This is not a lectotype, although Schlechter also included R. microphyllum J.J. Sm. in the section, as according to Art. 22.6 of the ICBN there was no choice to be made: the sectional name is derived from one if its constitutional species, which must be the type: R. linnaeoides Schltr.

sect. Malayovireya (Sleumer) Argent, Rhododendrons of subgenus Vireya. 21. 2006. Type: R. malayanum Jack

sect. Phaeovireya (Sleumer) Argent, Rhododendrons of subgenus Vireya. 21. 2006, nom. superfl . Type: R. beyerinckianum Koord.

sect. Pseudovireya (C.B. Clarke) Argent, Rhododendrons of subgenus Vireya. 19. 2006. Type: R. vaccinioides Hook.f.

sect. Siphonovireya (Sleumer) Argent, Rhododendrons of subgenus Vireya. 21. 2006. Type: R. habbemae Koord.

sect. Vireya (C.B. Clarke) H.F. Copel., Philipp. J. Sci. 40: 136, 151. 1929. Type: R. javanicum (Blume) Benn.

sect. Zygomorphanthe Schltr., Bot. Jahrb. Syst. 55: 140, 145. 1917. Lectotype: R. keysseri F. Först., designated by Sleumer (1960: 176). (This species is now included in R. culminicola F. Muell.)

The name sect. Phaeovireya (Sleumer) Argent is a nomen superfluum because, as circumscribed by Argent (2006), it contains the type of the valid name sect. Hadranthe and the latter name should have been adopted for the relevant section. Section Euvireya (H.F.Copel.) Argent also is a nomen superfluum as Argent (2006) based it upon the type of sect. Vireya (C.B. Clarke) H.F. Copel., i.e., R. javanicum .

There is no issue as to whether the English-language common name for the vireya rhododendrons should be changed to conform with the correction in the scientific name of the group. The group should continue to be called vireya as the common English name. This is analogous to use of the word "azalea" in which the common name bears no etymological relationship to the accepted scientific names. Garden plants derived from species of R. section Pentanthera G. Don are variously referred to as Mollis azaleas, Exbury azaleas, Ghent azaleas, etc. and plants derived from species of subg. Tsutsusi (Sweet) Pojark. have been called Indica azaleas, etc.

References
Argent, G. 2006. Rhododendrons of subgenus Vireya. Royal Horticultural Society, London, xii + 382 p.
Blume, C.L. 1826. Vireya. Bijdragen tot de Flora van Nederlandsch Indië 15: 854-856. Lands Drukkerij, Batavia.
Copeland, H.F. 1929. Philippine Ericaeae, I: The species of Rhododendron. Philipp. J. Sci. 40: 133-179.
McNeill, J., Barrie, F.R., Burdet, H.M., Demoulin, V., Hawksworth, D.L., Marhold, K., Nicolson, D.H., Prado, J., Silva, P.C., Skog, J.E., Wiersema, J.H. & Turland, N.J. 2006. International Code of Botanical Nomenclature (Vienna Code). (Regnum Vegetabile 146). Gantner, Ruggell, Liechtenstein, xviii + 568 p.
Schlechter, R. Die Ericaceen von Deutsch-Neu-Guinea. Bot. Jahrb. 55: 139-162.
Sleumer, H. 1949. Ein System der Gattung Rhododendron L. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 74:511-553.
Sleumer, H. 1960. Florae malesianae precursores XXIII: The genus Rhododendron in Malaysia. Reinwardtia 5: 45--231.
Sleumer, H. 1966. Rhododendron. 474-668. In, Flora Malesiana, Series I, 6. C.G.G.J. Van Steenis, ed. Wolters-Noordhoff, Groningen. [Reprinted as "An account of Rhododendron in Malesia" with an introduction and index.]

Lyn Craven is a taxonomist at the herbarium in Canberra. He has extensive field experience and has published many scientific papers on the taxonomy of plants from Australia and the southwest Pacific. His major research focus is on the myrtle and hibiscus families but he has a keen interest in vireyas.

Frédéric Danet is a botanist at the botanic garden in Lyon. He has been actively exploring for vireyas in Papua, Indonesia and has published several taxonomic papers on the group.

Jef Veldkamp is a taxonomist at the herbarium in Leiden. Jef has extensive field experience in the Malesian area, has published many scientific papers on the taxonomy of Malesian plants, and is an expert on the grass family. He also has a keen interest in plant nomenclature.

Loretta Goetsch is a former university research scientist who lives in Seattle, WA. At the University of Washington, she studied the cell biology of Saccharomyces and more recently the molecular systematics of Rhododendron. Currently, she is an active volunteer at the Rhododendron Species Botanical Garden.

Benjamin Hall is a Professor Emeritus of Biology and Genome Sciences at the University of Washington, Seattle. For many years, he studied the molecular genetics of yeast, then switched his attention to plants, Rhododendron in particular. Currently he is part of a small team sequencing the genome of Rhododendron williamsianum.