Hypericum hypericoides

(Linnaeus) Crantz

Inst. Rei Herb. 2: 520. 1766.

Common names: St. Andrew’s cross
Basionym: Ascyrum hypericoides Linnaeus
Treatment appears in FNA Volume 6. Treatment on page 87. Mentioned on page 74.
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Subshrubs or shrubs, erect or decumbent to prostrate, unbranched or branched, sometimes diffuse and mat-forming, 0.5–3 or 3–15 dm. Stems: internodes 2-winged. Leaf blades oblanceolate or narrowly oblong or elliptic to linear, 7–25 × 1–8.5 mm, base not articulated, usually cuneate, sometimes rounded, with glandlike auricles, margins subrecurved, apex rounded to obtuse, midrib with 1–2 pairs of branches. Inflorescences narrowly cylindric to pyramidal, 1–12-flowered from 1–4 nodes, sometimes with branches from to 10 proximal nodes, or branching more elaborate and pseudodichotomous; pedicels erect in fruit, bracteoles distal. Flowers 10–20 mm diam.; sepals persistent, enclosing capsule, 4, unequal, outer ovate-suborbiculate to narrowly elliptic, 5–12.5 × 2–13 mm, apex subapiculate to obtuse, inner lanceolate, 1–4 × 2 mm, apex acute; petals 4, bright to pale yellow, obovate to narrowly oblong-elliptic, 6–12 mm; stamens persistent, 40–50; ovary 2-merous. Capsules narrowly compressed-ovoid to cylindric-ellipsoid, 5–9 × 2–4 mm. Seeds not carinate, 0.6–0.8 mm; testa finely linear-reticulate to linear-foveolate.

Distribution

V6 144-distribution-map.jpg

c, e United States, Mexico, West Indies (Bahamas, Greater Antilles), Bermuda, Central America (Guatemala, Honduras).

Discussion

Subspecies 3 (2 in the flora).

Hypericum hypericoides can be distinguished from H. crux-andreae by the two-merous ovary, narrower leaves, smaller flowers, and more richly-branched stems. It is variable in leaf and sepal shape and size; three subspecies can be recognized.

The erect bushy form (subsp. hypericoides) is most widespread and has given rise to a northern diffuse form (subsp. multicaule) in the United States and a prostrate form (subsp. prostratum N. Robson) in Hispaniola.

Selected References

None.

Key

1 Plants erect, usually unbranched from base and freely branched well above ground level; leaf blades usually narrowly elliptic to narrowly oblong, broadest near middle. Hypericum hypericoides subsp. hypericoides
1 Plants decumbent to prostrate, branching from base; leaf blades usually oblanceolate, broadest beyond middle. Hypericum hypericoides subsp. multicaule
... more about "Hypericum hypericoides"
Norman K. B. Robson +
(Linnaeus) Crantz +
Ascyrum hypericoides +
St. Andrew’s cross +
c +, e United States +, Mexico +, West Indies (Bahamas +, Greater Antilles) +, Bermuda +, Central America (Guatemala +  and Honduras). +
Inst. Rei Herb. +
Ascyrum +, Crookea +, Sanidophyllum +  and Sarothra +
Hypericum hypericoides +
Hypericum sect. Myriandra +
species +