Scutellaria indica Linnae
- genus Scutellaria L.
Perennial herb. Stems dark purple, 1 to few, 12-28 cm tall, ascending-erect, ca. 1-1.2 mm in diameter, puberulent especially on angles and apex. Petiole 0.4-1.4 (-2.8) cm; Leaves cordate-ovate to elliptic, 1.5-2.6 (-3) cm long, 1.2-2.3 cm wide, base rounded to cordate, apex obtuse to rounded, puberulent or strigose, densely so abaxially. Racemes terminal, 4-8 (-12) cm; bracts sessile, 3-6 × 1-2.5 mm, margin entire, basal ones leaflike, ovate, to 1.7 cm, puberulent, margin crenate. Pedicel 2.5-3 mm, puberulent. Calyx ca. 2.5 mm, hirsute, puberulent; scutellum ca. 1.5 mm, erect, dilated to 3 mm in fruit. Corolla blue-purple, 1.4-1.8 cm, sparsely puberulent outside, pubescent on lips inside, to ca. 4.5 mm wide at throat; middle lobe of lower lip dark purple spotted, circular-ovate, slightly constricted at middle, apex emarginate; lateral lobes ovate. Nutlets chestnut to dark brown, ovoid, ca. 1 × less than 1 mm, tuberculate, tubercles acuminate with a minute apical whorl of hooks, adaxially umbonate near base.
Scutellaria indica var. indica is close relative of Scutellaria indica var. parvifolia, but differs from the latter in its cordate-ovate to elliptic (vs. cordate-ovate to ovate), 1.5-2.6 (-3) cm long, 1.2-2.3 cm wide (vs. 0.8-1.5 cm long, 0.8-1 cm wide) leaves, 1.4-1.8 cm long (vs. 1-1.5 cm long) corolla.
The chromosomal number of Scutellaria indica is 2n = 26 (Xu et al., 1992; Hsieh and Huang, 1995).
Ecology and Distribution
Flowering from February to June; fruiting from February to June.
Scutellaria indica is occurring in Anhui, Fujian, Guangdong, Guangxi, Guizhou, Henan, Hunan, Jiangsu, Jiangxi, Shaanxi, Sichuan, Taiwan, Yunnan, Zhejiang of China, Cambodia, India, Indonesia, Japan, Laos, Malaysia, Myanmar, Thailand, Vietnam.
Growing in hillsides, grasslands, open areas, roadsides, sparse forests; 100-1500 m.
Scutellaria indica was traditionally used as a remedy for traumatic injuries.
Scutellaria indica is a perennial herb with both chasmogamous (CH) and cleistogamous (CL) flowers on the same plant in some populations, and only CL flowers in other populations. The average seed set of CL flowers was 19 times higher than CH flowers, indicating much greater fertilization success. The CL seeds were also significantly heavier than the CH seeds. However, the resource cost of producing a CH flower was much higher than that of producing a CL flower. The CH flower was approximately seven times larger, and its pollen/ovule ratio was approximately five times higher than flowers. The level and pattern of genetic diversity at both allozyme and random amplified polymorphic DNA (RAPD) levels were consistent with a predominantly selfing system in the species. The average amount of within-population genetic variation was extremely low (A = 1.025, P = 2.36%, HO = 0.001 and HE = 0.008 based on allozyme data, and P = 8.94% and HE = 0.03 based on RAPD data). At the species level, the estimates of total gene diversity (HT) were 0.101 based on allozyme data and 0.139 based on RAPD data. A very high level of genetic differentiation occurred between populations (allozyme GST = 0.92 and RAPD GST = 0.81). Genetic drift coupled with predominant cleistogamous selfing apparently played the major role in determining the population genetic structure in Scutellaria indica. Although the features associated with CH and CL flower and seed production seem to be sufficient for the evolution of complete cleistogamy in S. indica, random fixation of alternative alleles for dimorphic or complete cleistogamy in small populations could maintain the multiple strategy of chasmogamous and cleistogamous reproduction in the species (Sun, 1999).
- Scutellaria indica Linnaeus var. indica f. ramosa C. Y. Wu & C. Chen (synonym)
- Scutellaria leucodasys Miquel (synonym)
- Scutellaria tashiroi Hayata (synonym)