Glabrous, annual or biennial, glabrous, whitish or glauous herb; stems 4-angled, many-branched, prostrate at base, 10-30 cm long. Leaves opposite, sessile, ovate, 10-25 mm long, 5-15 mm wide, spreading, the margins entire, acute to subobtuse at apex, rounded at base. Flowers axillary, the pedicels 2-3 cm long; calyx segments linear-lanceolate, long-acuminate, 4-6 mm long; corolla bluish-purple to reddish, the lobes obovate-orbicular, serrate at apex, often ciliolate. Capsules globose, the dehiscence circumscissile; seeds small, dark brown.
TAIPEI: Nankang, Peng 12496; Yehliu, Chuang 2096. TAOYUAN: Shalun, Peng 7723; Kuanyin, Leu 1717. HSINCHU: Lienhuashih, Peng 11541, Hsiangshan, Huang & Huang 13022. MIAOLI: Hsihu, Peng 13947. TAICHUNG: Tatushan, Hsu & Kouh 10761. CHANGHUA: Lukang, Ou & Kao 8895; Hsiensi, Huang 1461. TAINAN: Huwei, M. Ashiri 181; Chiali, Morimoto 48. PENGHU: Kudo & Mori 3095.
Distributed throughout temperate and south Asia, NW Africa, Australia, Europe, North and South Americad. Taiwan, in seashore and cultivated fields of low altitudes .
Phenology: biennial, annual
Life form: herb
Root: rooting at node or not: not rooting at node
Stem: present
Stem: type: prostrate at base, slender
Stem: shape: angled
Stem: indumentum: glabrous
Leaf: position: cauline
Phyllotaxy: opposite
Leaf: petiole: sessile
Leaf: blade shape: ovate
Leaf: blade apex: acute
Leaf: blade base: rounded
Leaf: blade margin: entire
Leaf: blade surface: glabrous
Leaf: blade texture: herbaceous
Leaf: blade length (mm): 10-25
Leaf: blade width (mm): 5-15
Inflorescence: solitary
Inflorescence: position: axillary
Scape: absent
Peduncle: length (mm): 20-30
Bract: absent
Calyx: shape: 5-parted
Sepal: shape: linear, lanceolate
Sepal: margin: entire
Sepal: length (mm): 3-6
Sepal: width (mm): 1-2
Corolla: color: purple, reddish, bluish
Corolla: shape: rotate
Lobe: margin: serrulate
Lobe: length (mm): 4-6
Lobe: width (mm): 2-4
Filament fused into a ring or not: filament fuse to a ring
Filament inserted position: base of corolla lobe
Filament: indumentum: hairy
Filament and anther relative length: filament obviously longer than anther
Stamens protruding from corolla or not: Stamens protuding from corolla
Capsule: dehiscence type: circumscissile
Distribution: seashores, low elevation cultivated field
