Cotoneaster perpusillus (C.K.Schneid.) Flinck & Hylmö

Prostrate shrub, deciduous. Branches in flattened distichous planes ("herringbone" pattern); branchlets red-brown, branchlet hairs moderately dense, yellow; stipule 1.8–3.0 mm long, red-brown and persistent, with sparse hairs. Leaves crowded on branches, 12–16 mm long, lamina 10–14 mm long, 6–8 mm wide, dark green (RHS 136A), elliptic or obovate, distinctly V-shaped, 200–270 µm thick, petiole 1.5–2.9 mm long, sparse to moderately dense, white or yellow; leaf base cuneate to almost obtuse; leaf apex obtuse to acute and cuspidate, apiculus straight; lateral veins in 2–3 pairs or none apparent, midvein only impressed above and projecting below; upper surface smooth, mid to dark green, glossy, upper-surface hairs usually absent, occasionally very sparse; margins plane, hairs sparse; lower surface glossy, not glaucous, hairs sparse, straight, white or yellow.

Inflorescence 1–2 flowers, 8–10 mm long, rachis hairs dense, pale yellow; pedicel 0–0.5 mm long, hairs moderately dense, yellow. Flowers 3.0–4.0 mm diameter. Hypanthium green turning red after flowering, sepals 1.7 mm long, 1.8 mm wide, hairs sparse, white. Petals red in bud, petals remaining almost closed, dark red centrally with red margins, 3.5 mm long, 2.8 mm wide, base not clawed, glabrous, margins torn. Stamens 8–11; filaments 1.5–2.7 mm long; red, anthers white, 0.7–1.0 mm long; styles 3, 1.0–2.1 mm long. Fruit vivid red (RHS 45A), obovoid, 6.0–6.4 mm long, 5.8–6.4 mm diameter, calyx closed, hairs very sparse. Pyrenes invariably 3, 4.2–4.4 mm long, 2.5–3.5 mm wide, hairs sparse at apex, style attached 1.4–2.1 mm below pyrene apex.

Recognised by Lu & Brach (2003) as C. horizontalis var. perpusillus. A synonym of C. horizontalis in Dickoré & Kasperek (2010). Recognised as a species by Fryer & Hylmö (2009). The two are distinct in New Zealand and so are recognised here as two species. It is possible that their distinctiveness in cultivation is because two apomictic forms of the same wild species have been selected.

A densely branched shrub up to 1.8 m tall. The branching is planar and in a regular herringbone pattern. The leaves are small, distinctly V-shaped, acute at the apex, glossy above, glossy and sparsely hairy below, not glaucous. The flowers have erect petals that are red centrally and pink at the edges, 8–11 filaments that are red, anthers white. Fruit are dense on the branches, solitary and vivid red.

Most similar to Cotoneaster horizontalis (q.v.). Both have flowers with erect petals that are red centrally and pink on the margins, red filaments and white anthers. Cotoneaster perpusillus has smaller leaves (6–8 mm wide, rather than 10–17 mm wide) that are more distinctly V-shaped in cross-section, and are consistently small in size (leaves near the main stem are usually larger in C. horizontalis than those on the branchlets). Flowers have 8–11 stamens (not 11–17). The fruit are smaller (c. 6 mm diameter, not 6.1–9.0 mm diameter).

CHR 481276, H. D. Wilson BP397, 22 Sept. 1984, Banks Peninsula, north end of Montgomery Reserve near Hilltop.

Flowering: mid-October to November; Fruiting: January to March, persisting over winter

Tetraploid (Fryer & Hylmö 2009), confirmed by flow cytometry using CHR 637373.