''Tricardia'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus of flowering plants in the

borage family Boraginaceae, the borage or forget-me-not family, includes about 2,000 species of shrubs, trees, and herbs in 146 to 154 genera with a worldwide distribution. The APG IV system from 2016 classifies the Boraginaceae as single family of the order ...

containing the single species ''Tricardia watsonii'', which is known by the common name threehearts. It is native to the southwestern United States, where it grows in deserts and mountains in sandy open habitat, often beneath

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

s. It is a perennial herb growing from a

taproot A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot ...

and a woody

caudex A caudex (: caudices) of a plant is a stem, but the term is also used to mean a rootstock and particularly a basal stem structure from which new growth arises.pages 456 and 695 In the strict sense of the term, meaning a stem, "caudex" is most ...

covered with the shreddy remains of previous seasons' herbage. It produces several erect stems up to about 40 centimeters tall. Most of the leaves are located in a basal rosette about the caudex. They are lance-shaped and coated thinly in woolly hairs. They are up to 9 centimeters long and are borne on petioles. A few smaller leaves occur higher on the stem. Flowers occur in a loose cyme at the top of the stem. Each has a calyx of five

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s. The outer three are heart-shaped and green to pink or purple in color, and the inner two are much smaller and narrower. The flower within is bell-shaped, white with central purple markings, and roughly half a centimeter wide. The fruit is a capsule just under a centimeter long which contains 4 to 8 seeds.

References

External links

Jepson Manual Treatment

Arizona Game & Fish Profile

Photo gallery
Hydrophylloideae Monotypic Boraginales genera Flora of the United States Boraginaceae genera {{Hydrophylloideae-stub