About Ourisia macrophylla Hook.
Ourisia macrophylla Hook. is a large species of perennial herb. It has creeping horizontal stems, with opposite leaves that grow in tight tufts along the stem. Leaf petioles measure 4.3–225.0 mm in length. Leaf blades are 10.4–160.0 mm long by 5.9–99.0 mm wide, giving a length-to-width ratio of 0.9–2.3:1. Blades are most often narrowly ovate to broadly ovate, widest below the middle, with an acute or rounded apex; a truncate, rounded, cuneate or cordate base; and crenate to crenate-serrate margins. Leaves may be glabrous, or have anywhere from few hairs to dense covering of non-glandular hairs on both surfaces, and the lower leaf surface is punctate. Inflorescences are erect hairy racemes that reach up to 64.8 cm long, with 1–6 flowering nodes per raceme and up to a total of 53 flowers per raceme. Each flowering node holds up to 12 flowers and 2–12 sessile bracts that sometimes clasp the stem; these bracts are usually narrowly lanceolate to narrowly ovate. The lowest bracts are similar in size to the plant's leaves, measuring 10.4–78.9 mm long and 4.0–32.0 mm wide, and bracts get smaller toward the apex of the raceme. Flowers are carried on a densely hairy pedicel up to 56.4 mm long; the pedicel has glandular hairs, and sometimes only non-glandular hairs in addition. The calyx is 3.6–10.0 mm long, regular, with all five lobes divided all the way to the base, and has isolated to sparsely distributed hairs, which are usually a mix of glandular and non-glandular types. The corolla is 10.3–22.2 mm long (including a 2.9–12.3 mm long corolla tube), bilabiate, and tubular-funnelform. It is usually hairy, white on the outside (sometimes flushed pink), and yellow on the inside, with three lines and a ring of yellow hairs inside. Corolla lobes are 3.1–11.1 mm long, spreading, and shaped obcordate or obovate-spathulate. There are 4 didynamous stamens up to 11.2 mm long: two long stamens that are exserted or reach the corolla tube, and two short stamens that also usually reach the opening of the corolla tube. A short staminode measuring 0.3–1.0 mm is also usually present. The style is 3.7–8.2 mm long, exserted, and has an emarginate stigma. The ovary is 1.6–4.4 mm long and glabrous. Fruits are capsules 4.3–8.6 mm long and 3.7–6.0 mm wide that undergo loculicidal dehiscence, carried on pedicels up to 74.6 mm long. The number of seeds per capsule is unknown. Seeds are 0.5–1.1 mm long and 0.2–0.4 mm wide, with a two-layered, reticulate seed coat. Ourisia macrophylla flowers from August to April and fruits from October to May. The chromosome number of this species is 2n=48. Ourisia macrophylla is endemic to New Zealand. The subspecies O. macrophylla subsp. macrophylla occurs on the North Island, in the Gisborne, Volcanic Plateau, Waikato, Taranaki, and southern North Island regions. The subspecies O. macrophylla subsp. lactea occurs on the South Island, in the Western Nelson, Marlborough, Canterbury, and Westland regions. This species most often grows below the bushline, in damp to wet sheltered areas within Nothofagus forest, near cliffs, tracks, streams or waterfalls. It can sometimes be found just above the bushline in partly shaded to open subalpine scrub or tussuck. It grows at elevations from 210 to 1,800 m (690 to 5,910 ft) above sea level, and can be very locally common.
