Taraxacum sect. Australasica
Content
Description
Flowers and leaves develop simultaneously. Plants usually delicate or small.Plant base whitish araneous or subglabrous to slightly araneous. Middle leaves sparsely araneous or subglabrous. Leaf at hair base not swollen, leaf surface flat. Leaves undivided or shallowly lobate to deeply lobed, lobation usually uncomplicated. Midrib without striatulate pattern. Leaf blade unspotted. Petioles narrow, unwinged. Scapes unbranched, growing from the centre of leaf rosette, subglabrous, sparsely araneous, or araneous, particularly below the capitulum. Capitulum after flowering pointing upwards. Involucre usually narrow at the base, usually 5-9 mm wide. Flowers yellow. Florets usually ± numerous. Ligules flat. Pollen present. Stigma discoloured (usually pale green). Outer and inner involucral bracts flat, without corniculation or horns at the apex, rarely very slightly callose. Outer bracts 10 to 14, imbricate or of ±equal length, adpressed, lanceolate-ovate, Prevailing colour of exterior bracts: pale green to deep green. Outer bracts narrowly bordered, almost glabrous or sparsely ciliate. Achenes pale greyish straw brown or of various coloration, brown, fulvous, reddish or deep red, with numerous, conspicuous or inconspicuous, longitudinal ridges, ± densely or sparsely spinulose above 3.5-6.0 mm long, gradually narrowing into the cone. Cone cylindrical to slightly subcylindrical, thin, 1.0-1.6 mm long. Rostrum thin, 5.0-9.0 mm long. Pappus 5.0-7.0 mmlong, white or whitish-yellow, not deciduous. Receptacle glabrous. Plants sexual (diploid). Main flowering season: late spring to early summer or summer (under lowland conditions).
from: Kirschner & al. in Folia Geobot. 39: 207. 2004.
from: Kirschner & al. in Folia Geobot. 39: 207. 2004.
Systematics
Traditionally the indigenous Australasian Taraxacum species were included in T. sect. Antarctica and the New Zealandian plants in T. magellanicum. Detailed examination of the type material of the names based on plants from Australia and New Zealand by Uhlemann & al. (2004) revealed, however, that they are clearly distinguished from South American plants. These authors state, that the combination of features such as adpressed, usually green to deep green, pale bordered outer phyllaries sexual reproduction (autogamy), and, in particular, the very thin, long, subcylindrical cone of 1-1.5 x 0.2 mm (in smaller achenes at least 1/3 as long as the coloured part of the achene, in longer achenes usually c. 1.5 mm long), qualifies the group as a separate section, T. sect. Australasica.
Uhlemann I., Kirschner J. & Štěpánek J. 2004: The genus Taraxacum (Asteraceae) in the southern hemisphere. I. The section Antartica Handel-Mazzetti and notes on dandelions of Australasia. – Folia Geobot. 39: 205–220. 2004
References
Uhlemann I., Kirschner J. & Štěpánek J. 2004: The genus Taraxacum (Asteraceae) in the southern hemisphere. I. The section Antartica Handel-Mazzetti and notes on dandelions of Australasia. – Folia Geobot. 39: 205–220. 2004