D. Jones & M. Clements, sp. nov.1
Synonymy: Diplodium dolichochilum, Pterostylis alata
Common name: Mallee green-hood.
Plant slender, 8-20 cm high; a small rosette of 3-6 ovate leaves on long peduncles in non-flowering plants; cauline leaves lanceolate, 2-5 cm x 3-6 ram, the larger ones above.
Flower single, maroon or brownish and white, striated; galea 25-35 mm long, firstly erect, gradually incurved, apex blunt, dorsal sepal blunt or shortly acuminate; petals blunt; lateral sepals (lower lip) erect, the lobes separated by a narrow to broad sinus notched at the middle, not bulging, the tips produced into long curved filiform points embracing the galea and greatly exceeding it; labellum on a movable claw, lamina lanceolate, c. 8 mm long, 1-1.2 mm broad, dark-green or brown, thin-textured; tip acuminate, decurved and protruding through the sinus of the lower lip, central keel not very distinct; basal appendages linear, curved, penicillate; column erect, winged, upper tip of the wings falcate, acute, lower lobe oblong, blunt with inturned ciliate margins; stigma prominent, 2-lobed, elliptic, centrally located on the column.
Fiveash & Lothian 1974) Australian orchids, pl. 59.
Forms extensive colonies on limestone or in calcareous sands in mallee or mallee heathland in areas receiving 300-500 mm annual rainfall.
S.Aust.: FR, EP, NL, MU, YP, SL, SE. Vic.
Flowering time: May — July.
SA Distribution Map based
on current data relating to
specimens held in the
State Herbarium of South Australia
This species has been confused with Pterostylis alata. The two species favour different habitats but where they are sympatric intermediates do not occur. A very low percentage of plants actually flower. Putative hybrids have been reported with P. robusta (MU).
Affinis Pterostylidi alatae(labill) H.G. Reichb., a qua flore parum robustiore rufo-brunneo-vittato, interdum viridi et albo; et labello elongato fere lineari per sinus multo exserto, differt. Holotype: South Australia, 20km E. of bow hill, in sand dunes under Callitris, (c. 34º53'S 139º37'E) 10 June 1981, R. Bates 959 (AD). Isotypes: AD, BRI, CBG
Not yet available