Australian Tropical Rainforest Plants - Online edition

Polyscias mollis (Benth.) Harms


Shrub (woody or herbaceous, 1-6 m tall)
Tree
Click/tap on images to enlarge
Flower and buds. © Barry Jago
Flowers. © CSIRO
Flowers. © CSIRO
Fruit. © CSIRO
Habit, leaves and fruit. © CSIRO
Scale bar 10mm. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Harms, H.A.T. in Engler, H.G.A. & Prantl, K.A.E. (1894) Die Naturlichen Pflanzenfamilien 3(8) : 45.

Stem

Usually grows as a multistemmed, poorly formed tree seldom exceeding 30 cm dbh but often flowers and fruits as a shrub. Stem clothed in conical spines.

Leaves

Leafy twigs, petioles and basal section of the compound leaf axis with numerous quite sharp prickles. Compound leaf rhachis swollen at its junction with the leaflets. Leaflet blades about 10-21 x 5-10.5 cm.

Flowers

Flowers in umbels which are arranged in panicles. Main axis of the inflorescence and base of the main branches clothed in prickles. Calyx lobes small. Petals about 2 mm long. Style arms free and divergent following anthesis.

Fruit

Fruits depressed globular in outline, but conspicuously laterally compressed, about 4.5-5 x 6 x 3 mm. Calyx lobes persistent at the apex. Style arms divergent, persisting at the apex of the mature fruit. Embryo very small.

Seedlings

Cotyledons broadly ovate or orbicular, about 5-7 mm long. First few leaves produced are simple. At the tenth leaf stage: leaves trifoliolate or pinnate; leaflets ovate, apex acuminate, base obtuse usually oblique, both the upper and lower surfaces with numerous prickle-like hairs; stipules or stipule-like appendages attached to the base of the petiole, triangular, hairy and prickly; petioles and stem clothed in numerous erect straight prickles. Seed germination time 49 to 70 days.

Distribution and Ecology

Endemic to NEQ, a rare species found between Cooktown and Cardwell. Altitudinal range from near sea level to 1100 m. Grows as a very small but extremely prickly tree in the rain forest understory.

Natural History & Notes

The word 'mollis' is usually used to describe something which is soft. The use of the epithet 'mollis' for this species seems to be particularly inappropriate as the stems, branches and even the compound leaf axes are clothed in sharp spines. It is difficult to avoid thinking that taxonomists have a strange sense of humour or we have completely misinterpreted their original species concept.

Synonyms
Tieghemopanax mollis (Benth.) R.Vig., Bulletin de la Societie Botanique de France 53 : 312(1905). Panax mollis Benth., Flora Australiensis 3: 382(1867), Type: Queensland. Rockingham Bay, Dallachy. Panax macdowallii F.Muell., Southern Science Record ser. 2, 2 : (1886), Type: On Russells River; Walter Hill. Aralia macdowallii (F.Muell.) F.M.Bailey, A Synopsis of the Queensland Flora, Supplement 2 : 31(1888). Polyscias macdowallii (F.Muell.) Domin, Bibliotheca Botanica 89(4): 1037(1928).
RFK Code
517
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