Flora of New Zealand Series

Spreading shrub; primocanes suberect to somewhat arching, greenish brown, with rounded angles and furrowed between, with numerous subsessile glands and sparsely to moderately clothed in simple hairs; armature of many, stout, erect to slightly deflexed prickles on angles. Young stems densely hairy and glandular. Leaflets 5, almost glabrous to sparsely pilose on upper surface, sparsely to moderately pilose on veins but not tomentose on lower surface, coarsely 1-2-serrate; terminal leaflet lamina ± elliptic, acuminate, 50-100 × 20-50 mm, with petiolule c. ?-1/4 length of lamina. Stipules linear-lanceolate. Infl. moderately to densely hairy, with subsessile glands. Sepals acuminate, moderately pilose but tomentose only on margins and within, without pricklets. Petals rounded, crinkled, white. Anthers glabrous.

N.: N. Auckland (Pipiwai, Whangarei district and Kamo).

N. America 1988

Wasteland, roadsides, streamsides.

FL Feb-May FT May.

This sp. is similar to R. ostryifolius which also occurs in N. Auckland but is more widespread. The late flowering and fruiting times recorded for N.Z. collections contrast with the early flowering and fruiting of R. ostryifolius; however, N. American Floras give flowering and fruiting times for R. argutus that correspond with those of R. ostryifolius in N.Z. The habit also appears to differ from that typical of the sp. in America where it is described as erect or high-arching up to 2.5 m.

One collection (CHR 417206, Mount Roskill, Auckland, Esler 6538, 24.10.1982) matches R. argutus in most characters but has slightly obovate terminal leaflets, 3 leaflets per primocane lf, some stellate hairs on the primocanes and infls and rather large fls similar to R. flagellaris. However, it is clearly distinguished from the latter by the leaflet shape, angled and furrowed stems, and reflexed fruiting sepals.