Thelymitra atronitida Jeanes APNI*
Description: Glabrous terrestrial herb.
Leaf linear to linear-lanceolate, 15–35 cm long by 5–12 mm wide, erect, leathery, analiculate, dark green with a purplish base, ribbed abaxially, sheathing at base, apex acute.
Scape 30–50 cm tall, 1.5–3.5 mm diameter, straight, straw-coloured to purplish. Sterile bracts usually 2, occasionally 3, linear to linear-lanceolate, 1.5–7 cm long, 3–10 mm wide, green or purplish, acute to acuminate. Fertile bracts ovate to obovate, 5–25 mm long, 3–8 mm wide, acuminate, sheathing pedicels. Pedicels 5–12 mm long, slender; ovary cylindric to narrow-obovoid, 5–12 mm long, 2–4 mm diameter. Flowers 2–8, (14-)20–26 mm across, moderately dark blue with darker longitudianl veins. Perianth segments (7-)10–13 mm long by 3–8 mm wide, concave, often shortly apiculate; dorsal sepal ovate to elliptic; lateral sepals elliptic to lanceolate, slightly asymmetric; petals ovate to elliptic; labellum elliptic to lanceolate, often narrower than other segments; column erect from the end of ovary, 5.5–7 mm long and 2.5–3.5 mm wide, mostly pale blue; post-anther lobe 3–4 mm long and 1.5–2.5 mm wide, tubular, inflated, hooded, dorsally compressed, gently curved through about 90 degrees, apex shortly bilobed, lobes toothed, mostly glossy black, apex yellow; auxiliary lobes absent; lateral lobes 1.3–1.5 mm long, filiform, porrect at base then bent sharply upwards at about the middle, converging, each with a terminal toothbrush-like arrangement of white hairs, the individual hairs 1.2–1.6 mm long. ANther ovoid, 2.6–3.3 mm long and 1.2–2.2 mm wide, with a short beak around 0.5 mm long, situated toward the column apex; pollinia 2–2.5 mm long, viscidium circular, around 0.5 mm diameter; pollen white, friable. Stigma ovate-quadrate, 1.7–2.5 mm long, 1.8–2.2 mm wide, margins irregular, situated at bas eof column.
Capsules obovoid, 12–15 mm long and 4–6 mm diameter, erect, ribbed.
Flowering: Late October to early November, opening readily only in hot weather.
Distribution and occurrence: From Sydney south to Victoria, on coast and tablelands. The concentration of records immediately south of the Victoria-NSW border suggest this species also occurs on the far southern coast of New South Wales, but has not been collected there yet.
Heathy open forest, on well-drained sand or clay loams.
NSW subdivisions: CC, ST
Other Australian states: Vic.
Threatened species: NSW BCA: Critically Endangered
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.