Chorizanthe orcuttiana is a rare small annual plant in the buckwheat family, Polygonaceae. It is known commonly as Orcutt's spineflower or the San Diego spineflower, and it is endemic to San Diego County, California. The plant is diminutive, and a hand-lens is necessary for proper identification. The plant is very sensitive to temperature and precipitation, and under drought or hot conditions the seeds will not germinate or survive. The plant is visible anywhere from February through July during good rain year, but most years the plant is only visible from April to June. Each minute flower yields one seed. Description This species is an annual herb, growing in a prostrate habit with the entire plant covered in dense, white, silky hairs. Before anthesis, the basal leaves form a rosette in diameter. The leaves are shaped narrowly oblanceolate, measuring long by wide, with an acute tip. C. orcuttiana also expresses two types of leaf shapes on different individuals, with one type being oblanceolate with an obtuse leaf apex and a reddish tinge on the upper surface, and the other slightly elongated. The leaves are attached to the plant via a pubescent petiole. The inflorescence is cymose. There may be awns on the inflorescence, and if there are, they usually measure . The involucres are in small clusters roughly across. There are 2 bracts, positioned opposite. In some plants, one of the two bracts tends to be laminar, oblanceolate, and awnless, while the one opposite to it is greatly reduced and terminated by a short, straight awn. The involucres are shaped campanulate, 3-angled and 3-ribbed and colored greenish. The involucres are faintly transversely ridged, with 3 teeth and hooked awns. The involucre tubes are long, and pubescent. The flowers first emerge in tight bundles in the center of the rosette, with each of the individual flowers enclosed inside an involucre. The flowers are large, covered in dense hair, and with a yellow perianth. There are 9 stamens attached at the top of the floral tube, with reddish anthers. Anthesis occurs in February, and within 30 days, the plants begin to branch. The branching plants are significantly larger, and reach between in diameter. Taxonomy This species is octoploid, and may have arose through ancient hybridization between other Chorizanthe, perhaps C. procumbens and C. polygonoides, leading to a doubling of the chromosomes. Characteristics This species co-occurs with other similar small plants, such as Mucronea