Our research focuses on the population dynamics of plants and how they are influenced by impacts of natural disturbances and global environmental change. We are particularly interested in the interactive effects of fire, grazing and drought in grasslands and woodlands in southern Australia, and how climate change, fragmentation and shrub encroachment affect ecosystems.

Thursday 19 May 2016

Follow-up to 'Where have all the Yamfields gone?"

Since my last Blog post, lamenting the loss of the Yamfields - particularly those dominated by the native daisy Murnong  - I've been made aware of a recent revision of the genus Microseris that now gives a new name to Murnong: Microseris walteri


Neville Walsh provides a nice overview of this revision in Muelleria 34: 63-67. With the publication of the first Asteraceae volume of the Flora of Australia, we now have a national perspective of the taxonomy of Microseris.


For many years, three distinct taxa have been recognised, but one of those has remained as an informal taxon only (Microseris sp. 3 or Microseris aff. lanceolata (Foothills)). This has been unfortunate, particularly given that, of the three entities involved, the informally recognised one has long been acknowledged as one of the most important food plants of aboriginal people of south-eastern Australia and for which the name Murnong has long been applied in Victoria.
The characteristic root system of Murnong, producing a plump, annually-replaced tuber, provides both the major food source and a critical taxonomic feature. The 'Murnong' form of M. lanceolata is a lowland, spring-flowering, summer dormant entity whereas montane to alpine forms (concordant with the type specimen of M. lanceolata) are summer-flowering and winter dormant. An existing name has been resurrected to describe Murnong - Microseris walteri - and the key to identification is provided below.
Root system of Microseris walteri (from Walsh 2016)





Key to Australian species of Microseris


1 Cypselas mostly 7–10 mm long; pappus scales 30–66 mm, hardly widened at base; ligules to c. 12 mm long; roots several, cylindrical or long-tapered, usually branched shortly below leaves; mostly from basalt plains of western Victoria and elevated sites in Tasmania ................................................................................................................................................................................................M. scapigera


1: Cypselas usually less than 7 mm long; pappus scales to c. 20 mm, noticeably widened at base; ligules usually more than 15 mm long; roots cylindrical or napiform, branched or not; lowland to alpine plants, rarely on basaltic soils...................................... 2

2 Pappus scales 10–20 mm, c. 0.3–0.5 mm wide at base; fleshy roots several, cylindrical to long-tapered, branching just below ground-level; alpine and subalpine NSW, ACT and Victoria ..........................................................................................................M. lanceolata

2: Pappus scales usually c. 10 mm, 0.5–1.3 mm wide at base; fleshy root expanding to a solitary, napiform to narrow-ellipsoid or narrow-ovoid, annually replaced tuber; lowlands of temperate southern WA, SA, NSW, ACT, Vic., Tas. ............................M. walteri

 

 

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