Hypericum tetrapetalum (Nomenclature)
Shrub or perennial herb woody at base, 0.2-1 m tall, erect, often unbranched, branches divaricate or ascending. Stems green, (2)4- lined and ancipitous when young, becoming 2-lined to terete; cortex exfoliating in strips or flakes; bark thin, reddish brown, not corky. Leaves sessile, (5-)8-35 x 4-15 mm, oblong-ovate or ovate to triangular-ovate, margin subrecurved, paler beneath, not glaucous, coriaceous, eventually deciduous at basal articulation, apex apiculate or obtuse to rounded, base cordate-amplexicaul; venation: only one pair of basal laterals visible; laminar glands dense, large; inframarginal glands dense. Inflorescence l(3)-flowered with branching pseudo-dichotomous, occasionally with short lateral branches from up to 3 nodes below; pedicels 3-12 mm long; bracts foliar. Flowers 20-30 mm or more in diam.; buds compressed-subglobose. Sepals 4, markedly unequal, not? enlarging in fruit; outer 7-13(-15) x 5.5- 9(-10) mm, broadly ovate, foliaceous, subapiculate to obtuse, base cordate, basal veins 3(5), unbranched; inner 7-15 x 2-c. 3 mm, narrowly lanceolate, acute, basal veins 1-3. Petals 4, bright yellow, 10-15 (or larger?) x 7-10 mm, 1.2-1.3 x sepals, obovate-oblong, with apiculus lateral, acute to incurved, acuminate. Stamens c. 100, longest c. 4.5-6.5, c. 0.45 x petals. Ovary 3-merous, 3-3.5 x 1.6-2 mm, pyramidal-ovoid to ellipsoid-ovoid, acute, placentation parietal; styles 3, 3-3.5 mm, 1-1.2 x ovary, divergent distally. Capsule c. 5-6 x 3.5-4, broadly ellipsoid-ovoid to subglobose, 3-lobed. Seeds blackish brown, c. 0.7 mm long, ecarinate; testa shallowly scalariform.
2n = 18 (n = 9, Adams in Robson & Adams, 1968).
Moist low pinelands and roadside ditches, on sandy soil; lowland.
U.S.A. (Florida and adjacent Georgia and Alabama), Cuba (Pinar del Rio).
H. tetrapetalum is a derivative of 25. H. crux-andreae, differing from it in the ovate to triangular-ovate leaves, which are strongly cordate-amplexicaul and sometimes grade in form into that of the outer sepals, although they are usually somewhat larger. The terminal pseudo- dichotomous inflorescence is also nearly always diagnostic, but the Alabama specimen cited is intermediate in this respect. These two species overlap in distribution in southern Georgia and northern Florida but do not otherwise intergrade morphologically.