Agrostis thompsoniae
S.W.L.JacobsSlender erect or ascending, loosely tufted annual. Culms very fine, to 40 cm high. Leaves basal, few to crowded; ligule to 5 mm long, obtuse, laciniate; blade mostly flat, to 2.5 mm wide. Panicle contracted, narrow-ovoid or nearly linear, more than twice as long as wide, to 12 cm long, distinctly exserted from upper sheath; branches appressed to ascending, ultimate branchlets usually straight. Spikelets 1.5–2.5 mm long, weakly purplish (in the single Victorian specimen seen); pedicels to 2 mm long, although terminal pedicels sometimes longer; glumes subequal or lower very slightly longer; lemmas 1.3–1.8 mm long, truncate, awnless; palea minute; anthers 0.3–0.5 mm long. Flowers summer.
HNF, VAlp. Also NSW, Tas. Currently known in Victoira by a few collections (Mts Buller, Buffalo, Hotham, Cobberas), where noted from seepage areas, gully heads and stream margins, but almost certainly more widespread than current records indicate.
Although in the original description of A. thompsoniae (Telopea 9:682, 2001), Jacobs cited a specimen from Nunniong Plain as belonging to this species (A.C.Beauglehole 36318), the immature anthers on this are >0.6 mm long and the general appearance is of a young plant of A. bettyae, a common species of this area. Accordingly, the specimen at Melbourne Herbarium has been reassigned to A. bettyae.
The distinction between A. thompsoniae and the apparently similarly rare A. joyceae, based principally on panicle shape and pedicel length appear to be slight. Further Victorian collections of these species are required to assess the reliability of these characters and to appreciate different ecological niches, if any. It is possible that both species are merely dwarfed, high-altitude forms of the widespread A. propinqua. Further research on this group is warranted.
