Amer. J. Sci. 1: 3781819.

Common names: Clammyweed
Etymology: Greek polys, many, and anisos, unequal, alluding to stamens
Synonyms: Cristatella Nuttall
Treatment appears in FNA Volume 7. Treatment on page 201. Mentioned on page 199, 200.

Herbs, annual or perennial (unscented). Stems sparsely or profusely branched; glandular-pubescent, viscid. Leaves: stipules absent or minute; petiole without pulvinus distally; leaflets 3. Inflorescences terminal or axillary (from distal leaves), racemes (flat-topped); bracts present (pedicels green to purple, glandular-pubescent). Flowers slightly zygomorphic; (receptacle prolonged into gland adaxially); sepals deciduous, distinct, equal; petals unequal (adaxial pair larger); stamens 8–32; filaments inserted on gynophore, (unequal), glabrous; anthers (ellipsoid), not coiling as pollen is released; gynophore ascending in fruit. Fruits capsules, dehiscent in distal 1/2, cylindric, oblong. Seeds 12–65, globose or subglobose, not arillate, (cleft fused between ends). x = 10.


North America, Mexico.


Species 5 (5 in the flora).


1 Leaflet blades obovate to oblanceolate or broadly elliptic, 0.5-2(-3) cm wide; styles deciduous in fruit, 5-40 mm > 2
1 Leaflet blades linear or narrowly elliptic, 0.05-0.2 cm wide; styles persistent in fruit, 2.5-4.5 mm > 3
2 Plants usually annual, rarely perennial; seeds roughened or tuberculate-rugose, 2-2.3 mm; stamens 10-20; styles 5-17 mm. Polanisia dodecandra
2 Plants perennial; seeds smooth, 0.7-2 mm; stamens 20-27; styles 20-40 mm (New Mexico, Texas). Polanisia uniglandulosa
3 Adaxial petals 6-11 mm; nectary glands 1-5.5 mm; gynophore 3-14 mm in fruit. Polanisia erosa
3 Adaxial petals 3-5 mm; nectary glands 0.5-1 mm; gynophore 1-4 mm in fruit > 4
4 Capsules 8-30 mm; seeds 1.8-2 mm; Great Plains, midwestern states. Polanisia jamesii
4 Capsules 40-60 mm; seeds 0.7-0.9 mm; southeastern states. Polanisia tenuifolia