Poa astonii Petrie
≡P. astonii Petrie var. astonii (autonym Zotov 1943 op. cit. p. 236);
Lectotype: WELT 66186! D. P[etrie] Brighton, near Dunedin (designated by Edgar 1986 op. cit. p. 439).
=P. oraria Petrie, T.N.Z.I. 42: 196 (1910)
≡P. astonii var. oraria (Petrie) Zotov, T.R.S.N.Z. 73: 236 (1943);
Lectotype: WELT 66041! B. C. Aston Deep Cove, West Coast Sounds, Otago, Jan. 1909 (designated by Edgar 1986 op. cit. p. 439).
Tightly packed, wiry-leaved small glaucous tussocks, 10-40 cm, spreading in narrow fans from a slender rhizome; branching intravaginal; leaf-blades disarticulating at ligule. Leaf-sheath light brownish to stramineous, sometimes purple, glabrous, shining, ± coriaceous with broad membranous margins, ribs inconspicuous. Ligule 1-2 mm, apically glabrous, entire, rounded and slightly tapered, abaxially slightly scabrid near base, or densely scabrid throughout. Leaf-blade (5)-10-30-(40) cm × 0.5-1 mm diam., inrolled, not keeled, usually erect, occasionally curled above, abaxially glabrous, adaxially pubescent, tip long-acicular. Culm (5)-20-30-(45) cm, ≤ leaves, internodes glabrous. Panicle 5-10-(12) cm, narrow, stiff; branches short, ± erect, glabrous to finely pubescent-scabrid, tipped by few, large spikelets. Spikelets 5.5-12 mm, 3-6-(8)-flowered, light greenish brown. Glumes subequal, subacute to acuminate, ovate to elliptic-lanceolate, ± smooth, occasionally a few prickle-teeth on midnerve near tip; lower 2-5-(6) mm, 1-3-nerved, upper 2-5.5-(7) mm, 3-(5)-nerved; margin finely ciliate. Lemma 3.5-7 mm, 3-5-nerved, elliptic-lanceolate, acute to acuminate, usually shortly mucronate, outer lateral nerves very distinct, internerves minutely scabrid or very rarely smooth, or prickle-teeth fewer between lateral nerves and keel, but always very dense and in several rows along keel, with longer crinkled hairs on lower ½ of midnerve, and near base of lateral nerves, often also on internerves near base; margins finely fimbriate. Palea 3-6 mm, keels and flanks with dense short prickle-teeth or minute hairs, the teeth on keels arranged in several rows, interkeel with minute prickle-teeth or hairs, often almost glabrous centrally; rarely palea glabrous except at fimbriate tip. Callus with short tuft of crinkled hairs. Rachilla 0.5- c. 1 mm, with sparse, short, fine hairs, or densely to minutely finely scabrid; prolongation twice as long. Lodicules 0.5-1 mm, occasionally hair-tipped. Anthers c. 2-3 mm. Caryopsis c. 1.5 × 0.5 mm. 2 n = 28. Plate 4A.
S.: Canterbury on Banks Peninsula near Akaroa Heads, Otago south from Dunedin and in Fiordland; St.: and on islands nearby; Solander Id, Sn., A., C. Coastal, on beaches or rocky cliffs.
Endemic.
Specimens from coastal cliffs near Dunedin have small spikelets (5.5-9 mm), short, ovate-elliptic glumes (2-3.5 mm) and shortly mucronate lemmas (3.5-4.5 mm), whereas many specimens from Fiordland, those from the Snares, and some from Southland, Stewart Id and the Subantarctic Is, have longer spikelets (8-12 mm), longer, narrower glumes (3-5.5-(7) mm), and longer very acuminate lemmas (5-7 mm). Both forms are present in some localities and there is no obvious definite geographical or ecological separation between the two kinds.
A specimen of P. astonii from the south-western Mutton Bird Is (CHR 261888) has proliferation in its spikelets.
The only known specimen from Canterbury was collected from Palm Gully, near Akaroa Heads, H. D. Wilson 4.12.1984 (CHR 417312). There are also some specimens collected by Buchanan from Nelson (WELT 65918, WELT 66313 and CHR 29296) but with no further details of locality or date of collection.
No recent collections of P. astonii have been made from Auckland and Campbell Is.
