Taxonomic notes on the New Zealand flora: the status of four varietal names in Brachyglottis (Asteraceae), Corokia (Argophyllaceae), Mida (Nanodeaceae) and Teucridium (Labiatae)

ABSTRACTTaxonomic names at the rank of variety are often poorly understood and may be misapplied as their taxonomic circumscriptions can be inadequate. These names often fall out of favour or are neglected until they are eventually abandoned, but uncertainty can remain as to their taxonomic or nomenclatural status. While many variety names persist in the New Zealand flora literature and databases, unlike naming a new taxon there are no formal rules or guidelines for not accepting a name and placing it in synonymy. The taxonomic recognition of four varietal names accepted in the Flora of New Zealand Volume 1 (Allan Citation1961) are assessed against the species to which they are assigned to determine if they warrant continued recognition. These varietal names are Brachyglottis bidwillii var. viridis (Kirk) B.Nord. (Asteraceae), Corokia buddleioides var. linearis Cheeseman (Argophyllaceae), Mida salicifolia var. myrtifolia (A.Cunn.) Allan (Nanodeaceae) and Teucridium parvifolium var. luxurians Cheeseman (Labiatae). For each of these taxa, and the species to which they were assigned, the key characters circumscribing them were analysed. Each of the four varieties are not significantly different from the species to which they have been assigned and are therefore treated as synonyms. While the means of the type species and variety are different, this is not surprising as typically the variety is named for plants that have particularly wide or narrow leaves that mostly occur in a particular part of the range of phenotypic variation. Scatter plots confirm the leaf variation is continuous with no discrete groups. Discriminant analyses demonstrate that specimens were correctly named in only a relatively low percentage of cases, suggesting the measurement ranges are insufficient for reliable recognition and indicative of overlap between the two taxa. Accepted names are listed and a full synonymy is provided, including where necessary the typification of names.KEYWORDS: Brachyglottis bidwillii var. viridisCorokia buddleioides var. linearisMida salicifolia var. myrtifoliaNew Zealand floranomenclaturesynonymtaxonomyTeucridium parvifolium var. luxuriansTeucrium AcknowledgementsI thank the Curators at Auckland War Memorial Museum (AK) and Museum of New Zealand Te Papa Tongarewa (WELT) for access to the collections; and Kerry Ford for comments on the draft manuscript. This research was supported by Strategic Science Investment Funding (SSIF) for Crown Research Institutes from the Ministry of Business, Innovation and Employment’s Science and Innovation Group.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by Ministry of Business, Innovation and Employment.