Common name: Guinea Grass
Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs APNI* Synonyms: Panicum maximum Jacq. APNI*
Description: Densely tufted perennial to 3 m high with a short stout rhizome covered with the hairy remainders of cataphylls.
Sheaths with tubercle-based hairs to glabrous, often densely bearded at the orifice; ligule membranous, 1.5–6 mm long; blade 5–18 mm wide, glabrous, softly hairy or coarsely hirsute with tubercle-based hairs.
Inflorescence at length much exserted, 15–50 cm long; pedicels mostly 1–6 mm long. Spikelets subobtuse to acute, 2.5–4 mm long, glabrous or pubescent. Lower glume obtuse, c. 20–35% the length of the spikelet, 1–3-nerved; upper glume the size and shape of the spikelet, 5-nerved. Lower lemma male, similar to the upper glume, 5–7-nerved; palea slightly shorter than the lemma. Fertile lemma oblong to elliptic, 2.2–3 mm long, finely transversely rugulose.
Flowering: Summer.
Distribution and occurrence: Native of Afr. Planted as a pasture species, also a weed of roadsides and disturbed sites.
NSW subdivisions: *NC, *CC, *NT, *NWS, *CWS, *NWP, *NFWP
Other Australian states: *Qld *N.T. *W.A.
The variety Megathyrsus maxima var. pubiglumis (K.Schum) B.K.Simon & S.W.L. Jacobs (commonly referred to as Panicum maximum var. trichoglume) is not accepted in some contemporary accounts because the character of spikelet pubescence is said to show continuous variation to the glabrous state. This does not appear to be the situation in populations growing in Australia, in that the spikelets are either glabrous or hairy, and the variety is accepted by APC.
Text by Jacobs, S.W.L., Whalley, R.D.B. & Wheeler, D.J.B.
Taxon concept: Grasses of New South Wales, Fourth Edition (2008).
| | Key to the varieties | |
| 1 | Glumes and sterile lemma glabrous | var. maximus |
| Upper glume and sterile lemma loosely and softly pubescent | var. pubiglumis |
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.
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