New research published by Jessie Prebble and colleagues resolves the taxonomy (naming and classification) of a group of small native forget-me-nots in the southern hemisphere. The new data show that some of these plants require different names. Curator Botany Heidi Meudt discusses what this means.

The main findings

The species treated in this new paper (Prebble et al. 2022) are mostly found in mainland New Zealand, but one species extends into the subantarctic islands and southern Chile. They include some of the smallest species of forget-me-nots in the world: Myosotis brevis, M. antarctica, M. drucei, M. pygmaea and M. glauca.

This paper is based on Jessie’s PhD thesis and is the culmination of a decade of research! Here, Jessie brought together her previously published data of these species’ morphological features and DNA, and combined them with new data on their ecological niches.

Jessie found that Myosotis brevis and M. glauca can be distinguished from each other and from the other species in multiple ways.

By contrast, M. antarctica from the subantarctic islands (which Jessie collected back in 2013!) is not different from M. drucei on mainland New Zealand.

A new taxonomy means some new names

Jessie’s findings show that instead of five species in this group, there are only three species. Her new taxonomy means that the species M. antarctica is expanded to include species formerly called M. drucei and M. pygmaea. 

But because those two former species show geographic separation (allopatry) and can be distinguished by minor leaf hair characters, they are now recognized as subspecies within M. antarctica. 

Although we’ll all have to learn some “new” names for these forget-me-nots, particularly for Myosotis drucei and M. pygmaea, the subspecies names themselves are not actually new. The name Myosotis antarctica subsp. traillii was published by New Zealand botanist Thomas Kirk back in 1884.

References cited

• Kirk T (1884) Description of new plants collected on Stewart Island. Transactions and Proceedings of the New Zealand Institute 16, 371–374.
• Prebble JM, Symonds VV, Tate JA, Meudt HM. 2022. Taxonomic revision of the southern hemisphere pygmy forget-me-not group (Myosotis; Boraginaceae) based on morphological, population genetic and climate-edaphic niche modelling data. Australian Systematic Botany 35(1):63-94.