Hypericum australe (Nomenclature)
Perennial herb 0.08–0.4 m tall, erect to ascending sometimes from prostrate, rooting base, with stems ± numerous, caespitose or spreading, usually unbranched below inflorescence. Stems narrowly 2-lined, eglandular; internodes 5–32(–42) mm, shorter than to exceeding leaves. Leaves sessile or rarely to 0.7 mm petiolate, subappressed to spreading; lamina 5–25 × (2–)4–9 mm, upper oblong to lanceolate or linear, lower elliptic or ovate-elliptic to obovate or oblanceolate, rather paler beneath, chartaceous; apex rounded, margin plane, base subamplexicaul or rounded to narrowly cuneate; venation: 1–4 pairs of main lateral veins from lower ⅓–½ of midrib, branching and reticulating; laminar glands absent; marginal glands black, spaced, subregular. Inflorescence (1–)3–c. 18-flowered, from 1–3 nodes, sometimes with flowering branches from one node below, the whole broadly rounded-pyramidal; pedicels 3–10 mm; bracts and bracteoles narrowly oblong or lanceolate to linear, entire. Flowers 10–20 mm in diam.; buds ovoid-ellipsoid, obtuse. Sepals 5, equal or subequal, free, (2.5–)3.5–5 × 1–1.5 mm, lanceolate to narrowly oblong or narrowly ovate, acute (or occasionally apiculate) to obtuse, entire or with sessile or prominent glands or short glandular cilia; veins 5, unbranched; laminar glands nearly always all black, punctiform to linear; marginal glands black or absent. Petals 5, rich yellow, tinged and veined red, 7–11 × 3–5 mm, 1.5–2 × sepals, oblanceolate to narrowly oblong, rounded; laminar glands pale, linear to punctiform, and often black, distal, striiform to punctiform; marginal glands black, distal, irregular. Stamens 30–36, longest 6–8(–10) mm, 0.85–0.9 × petals. Ovary 2.5–4 × 1–1.5 mm, ± narrowly ovoid; styles 3, 3.5–5 mm, 1.5–2.5 × ovary. Capsule 6–8 ×4-5 mm, 1.6–2 × sepals, narrowly to rather broadly ovoid; valves with numerous longitudinal vittae. Seeds cupreus, 0.6–0.8 mm; testa finely linear-reticulate.
2n = 18 (Humphries et al., 1978; Reynaud, 1986).
Woodland, scrub or grassy slopes, usually damp, on sand, schist or rarely limestone; 0–1000 m.
Southeastern France, Italy, Sicily, Tunisia, Algeria, Morocco?, Balearic Islands (Menorca), Sardinia, Corsica.
Hypericum australe is a west Mediterranean species that shares with the even farther western H. linariifolium primitive characters that indicate that Sect. Oligostema is directly derived from Sect. 10. Olympia, more precisely, from or near H. olympicum f. olympicum. Thus, the stout erect habit and sometimes rather broad leaves of some Iberian H. linariifolium would appear to be nearer to H. olympicum than the usually ascending stems and relatively broader leaves of H. australe, but the latter species has sepals that are usually entire or with few sessile glands, whereas those of H. linariifolium are more advanced than those of H. australe in their constantly glandular-ciliate margin,
The most primitive form of H. australe seems to be in Tunisia and eastern Algeria, whence there are reduction trends westward in Africa and northward through Sicily and Italy to southwest France, northern Sardinia and Menorca. In Sardinia (eg. Humphries & Richardson 142) and Corsica, some plants have elongate, creeping stems that seem to indicate a trend towards 5. H. humifusum. This tendency to creep has been recorded also from northern Italy, where the distributions of these two species overlap; but whether these intermediates indicate hybridity or (more likely) incomplete separation of taxa is unclear. Although Rouy (1896) and Fiori (1896-98) treated H. australe as (respectively) a subspecies or variety of H. humifusum, it seems unwise to reduce these taxa to subspecific rank unless or until more evidence in favour of this change is forthcoming.