Japanese name: オオイヌノフグリ（大犬陰嚢） Scientific name:Veronica persica
[Overview]
A winter annual 10–20 cm tall, commonly seen in fields, along roadsides and in vacant lots.
It germinates in autumn and overwinters, then flowers and fruits in spring and dies, passing the summer as seed.
The stems branch freely at the base and spread in all directions, with the upper parts rising obliquely.
The stems are sparsely hairy.
Leaves are simple, opposite on the lower part of the stem and alternate on the upper part.
They are ovate-round, 7–18 mm long and 6–15 mm wide, with sparse hairs on both sides.
The leaf margin has 3–5 pairs of large blunt teeth.
A long flower stalk extends from each leaf axil and bears a single flower.
The corolla is 4-lobed, 7–10 mm across, and azure with conspicuous dark blue lines.
The flowers open in sunlight and fall after one day.
The fruit is a slightly flattened, obcordate capsule with a notched tip.
[History]
It became naturalized in Tokyo in the early Meiji period (around 1887) and then spread throughout the country.
