Diapensia

Linnaeus

Sp. Pl. 1: 141. 1753.

,

Gen. Pl. ed. 5, 69. 1754 ,.

Common names: Pincushion plant
Etymology: Greek dia-, composed, and pente, five, alluding to sepal, petal, and stamen numbers
Treatment appears in FNA Volume 8. Treatment on page 337. Mentioned on page 332, 333.

Subshrubs, forming tussocks, cushions, domes, or mats, caulescent, taprooted. Stems mostly prostrate to decumbent, branched; branches procumbent or decumbent to erect. Leaves cauline, mostly opposite or compactly whorled, densely imbricate or crowded, 3–15 mm; petiole present or absent; blade oblong-lanceolate to narrowly spatulate, obovate, or spatulate-elliptic, slightly falcate, margins entire, apex acute or obtuse, surfaces glabrous, appearing 1-veined, sometimes with 1–2, indistinct, lateral-veins. Inflorescences solitary flowers, pedicellate to subsessile, immediately subtended by 2–3 bracts. Pedicels ebracteate, elongating after anthesis. Flowers: sepals distinct or connate proximally; petals connate in proximal 1/2, corolla cupulate to campanulate, 7–10 mm, lobes white to cream or pinkish tinged to rose, margins entire; anthers 2-locular, without basal spurs, longitudinally dehiscent; filaments adnate to corolla-tube; staminodes absent or vestigial. x = 6.

Distribution

North America, n Europe, Asia

Discussion

Species 5 (2 in the flora).

The three temperate species of Diapensia are endemic to the Sino-Himalayan Mountains. They differ as a group from the two boreal species by their production of vestigial staminodes (see F. Ludlow 1976).

Selected References

None.

Key

1 Plants forming tussocks; branches not adventitiously rooted; leaf blades oblong-oblanceolate to narrowly spatulate, 7-15 × 1.3-2.3 mm, margins with narrow hyaline flange proximally. Diapensia lapponica
1 Plants usually forming mats or low mounds or cushions; branches adventitiously rooted; leaf blades obovate to spatulate-elliptic, 3-8(-12) × 1.5-2.2(-3) mm, margins sometimes with narrow hyaline flange. Diapensia obovata
... more about "Diapensia"
Guy L. Nesom +
Linnaeus +
dentate-serrate +  and entire +
falcate;oblong-lanceolate;narrowly spatulate obovate or spatulate-elliptic +
decumbent to erect +  and procumbent +
Pincushion plant +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
North America +, n Europe +  and Asia +
straight;curved +
Greek dia-, composed, and pente, five, alluding to sepal, petal, and stamen numbers +
loculicidal +
pedicellate +  and subsessile +
crowded +, imbricate +, whorled +  and opposite +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
white +  and cream or pinkish tinged +
tenuinucellate +, bitegmic +  and hemitropous +
amphitropous +, campylotropous +  and anatropous +
elongating +
Sp. Pl. +  and Gen. Pl. ed. +
cylindric +
connate +  and distinct +
epipetalous +  and antisepalous +
spatulate +  and scale-like +
mostly prostrate +  and decumbent +
slightly 3-lobed;unlobed +
Diapensia +
Diapensiaceae +
taprooted +  and caulescent +
evergreen +  and perennial +