3. Tuberaria (Dunal) Spach, Ann. Sci. Nat., Bot., sér. 2. 6: 364. 1836. name conserved.
[Latin tuber, swelling, and -aria, possession, alluding to swellings on roots] [Latin tuber, swelling, and -aria, possession, alluding to swellings on roots]
John L. Strother
Helianthemum Miller sect. Tuberaria Dunal in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 1: 270. 1824
Herbs annual [perennial], 0.3–2(–3)[–8] dm. Leaves mostly opposite, <basal soon withering, sometimes in rosettes, distal cauline sometimes alternate>, stipulate or estipulate, petiolate or sessile; blade usually 3[–5]-veined from base, margins sometimes revolute, <surfaces hairy [glabrous], hairs sometimes clustered (stellate)>. Inflorescences racemiform [helicoid, scorpioid] cymes. Pedicels present; bracts [present or] absent. Flowers chasmogamous and cleistogamous, <nodding or pendulous in bud>. Chasmogamous flowers: sepals <persistent>, 5, <outer smaller than [equaling] inner>; petals 5, yellow, sometimes purple to brown at or near bases; stamens 10–15+; <filaments distinct, outer stamens often sterile>; carpels 3; styles 0; stigmas 1, <± sessile, hemispheric [obconic]>. Cleistogamous flowers similar; petals 0; stamens 5–12. Capsules 3-valved. Seeds 6–50+ per capsule. x = 9.
Species 8–12 (1 in the flora): introduced, California; c, w Europe, n Africa.
Tuberaria differs from Crocanthemum and Helianthemum primarily in habit, mostly opposite leaves, and sessile or subsessile stigmas.