Erigeron mariposanus Congdon

Erigeron mariposanus is closely similar to E. aequifolius.

Perennials, 15–28 cm; taprooted (root or caudex branches 1–4 cm, rhizomelike or caudexlike). Stems decumbent-ascending (distal branches spreading-ascending, axillary tufts of smaller leaves prominent at most nodes), sparsely to moderately strigose (hairs ascending-appressed), eglandular. Leaves cauline; blades oblanceolate, (25–)30–45 × (2–)5–8 mm, reduced near heads, margins entire, faces sparsely to moderately strigose, eglandular. Heads 1 or 2–4 (in loosely corymbiform arrays). Involucres mostly 4–5 × 8–12 mm. Phyllaries in 3–5 series, outer (midnerves prominently orange-resinous) sparsely strigose (hairs thin-based), eglandular (inner: margins broadly scarious, nearly winglike). Ray florets 18–22; corollas bluish, 5–8 mm, laminae sometimes coiling slightly at tips. Disc corollas 4–4.5 mm (throats slightly indurate, not inflated). Cypselae 2–2.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 28–32 bristles.

Erigeron mariposanus is a rare species of flowering plant in the family Asteraceae known by the common names foothill fleabane, Mariposa daisy, or Mariposa erigeron. It has been found only in a few locations in Mariposa County in California. Some sources say that it is now probably extinct.

Erigeron mariposanus is a perennial herb up to 28 centimeters (11 inches) tall, producing a woody taproot. The leaves and the stem are covered with hairs. The plant generally produces 1-4 flower heads per stem, each head with up to 22 blue ray florets surrounding numerous yellow disc florets.

Erigeron mariposanus là một loài thực vật có hoa trong họ Cúc. Loài này được Congdon mô tả khoa học đầu tiên năm 1900.