Austrodolichos Verdc.

Scientific Description

Family Papilionaceae. Phaseoleae.

Sometimes included in Leguminosae.

Habit and leaf form. Strigose herbs, or herbaceous climbers; not resinous. Plants unarmed. Perennial. Leaves cauline. Plants with neither basal nor terminal concentrations of leaves; tuberous. Self supporting, or climbing; stem twiners, or scrambling. When twining, twining anticlockwise. Mesophytic. Leaves medium-sized; not fasciculate; alternate; spiral, or distichous; not decurrent on the stems; ‘herbaceous’; not imbricate; petiolate. Petioles wingless. Leaves non-sheathing; not gland-dotted; compound; pulvinate; ternate. Leaves pinnately trifoliolate. Leaves imparipinnate. Leaflets 3; 2.4–5 cm long; stipellate; pulvinate; ovate; flat; with conspicuous lateral lobes to without lateral lobes. Leaflet margins flat. Leaf blades dorsiventral; cross-venulate. Mature leaf blades adaxially scabrous, or pubescent (‘sparsely strigose’); abaxially scabrous, or pubescent (‘sparsely strigose). Leaves with stipules. Stipules intrapetiolar. Stipules not peltate. Stipules free of the petiole; free of one another; scaly, or leafy; persistent. Leaf blade margins entire; not prickly. Leaves without a persistent basal meristem. Leaf anatomy. Hairs present; glandular hairs absent. Branched hairs absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring, or anomalous.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the disk. Pollination mechanism conspicuously specialized.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; not crowded at the stem bases; in racemes. Inflorescences simple. The terminal inflorescence unit racemose. Inflorescences terminal, or axillary; of slender, often twining, pedunculate racemes. Flowers pedicellate to subsessile; bracteate. Bracts deciduous. Flowers (bi-) bracteolate (the bracteoles conspicuous, subtending the calyx). Bracteoles persistent. Flowers small to medium-sized; very irregular; zygomorphic. The floral asymmetry involving the perianth and involving the androecium. Flowers papilionaceous (imbricate-descending); basically 5 merous; tetracyclic. Floral receptacle with neither androphore nor gynophore. Free hypanthium present, or absent. Hypogynous disk present; intrastaminal. Perianth with distinct calyx and corolla; (9–)10; 2 -whorled; isomerous, or anisomerous. Calyx present; 4, or 5 (the posterior members more or less completely connate); 1 -whorled; gamosepalous; lobed; blunt-lobed. Calyx lobes markedly shorter than the tube. Calyx imbricate (the lobes noticeably overlapping at the base); exceeded by the corolla; bilabiate; neither appendaged nor spurred; non-fleshy; persistent; non-accrescent; with the median member anterior. Calyx lobes broadly ovate. Corolla present; 5; 1 -whorled; appendiculate (the petals auriculate). Standard appendaged (auriculate, ‘with two ridgelike, parallel calli’). Corolla partially gamopetalous. 4 of the petals joined. The joined petals anterior (and lateral). The wings of the corolla adherent to the keel; not laterally spurred. Standard ‘normally’ developed; emarginate; not sericeous. Keel conspicuously exceeded by the wings, or about equalling the wings; not long-acuminate/beaked (blunt); neither coiled nor spiralled; not bent and beaked (incurved, blunt). Corolla imbricate (descending); glabrous abaxially; glabrous adaxially; yellow, or pink, or purple (or mauve); deciduous; non-accrescent. Petals clawed. Androecial members definite in number. Androecium 10. Androecial members free of the perianth; markedly unequal (the filaments alternately long and short); coherent; 2 - adelphous (the vexillary member separated from the tube?); 1 -whorled. Androecium exclusively of fertile stamens. Stamens 10; all more or less similar in shape; diplostemonous; both opposite and alternating with the corolla members; filantherous. Filaments club-shaped (the vexillary member hooked basally). Anthers connivent; all alike; dorsifixed; versatile; dehiscing via longitudinal slits; latrorse, or introrse; tetrasporangiate. Pollen shed as single grains. Gynoecium 1 carpelled. The pistil 1 celled. Carpels reduced in number relative to the perianth. Gynoecium monomerous; of one carpel; superior. Carpel stylate; apically stigmatic. Style flattened. Style glabrous. Carpel 6–100 ovuled (‘many’). Placentation marginal (along the ventral suture). Gynoecium median (the placenta posterior, on the ventral suture). Ovary sessile. Ovary summit hairy, the hairs not confined to radiating bands (sericeous). Ovules funicled; pendulous to ascending; biseriate; arillate; anatropous, or campylotropous to amphitropous, or hemianatropous.

Fruit and seed features. Fruit aerial; 75–95 mm long; sessile; non-fleshy; hairy (tomentose); not spinose. The fruiting carpel dehiscent; a legume. Pods much elongated; not triangular; straight; beaked; not becoming inflated; somewhat compressed; irregularly constricted, or not constricted between the seeds; more or less transversely septate between the seeds (with pithy tissue); wingless; not internally hairy. Valves of the dehisced pod not twisted. Fruit 1 celled; elastically dehiscent. Dispersal unit the seed. Fruit 5–50 seeded (‘many’). Seeds non-endospermic; not mucous; transversely ellipsoid; small, or medium sized; arillate; not conspicuously hairy. Cotyledons 2; accumbent. Embryo curved, or bent. Testa hard; non-operculate; smooth; conspicuously colour-patterned (mottled). Micropyle zigzag, or not zigzag.

Special features. Calyx limb 4 lobed, or 5 lobed. Upper lip of calyx entire to lobed; 1–2 lobed. Lower lip of calyx lobed; 3 lobed.

Geography, cytology, number of species. Native of Australia. Australian states and territories: Western Australia, Northern Territory, and Queensland. A genus of 1 species; 1 species in Western Australia; A. errabundus (M. Scott) Verdc.