128. Ipomoea petrophila House, Bot. Gaz. 43 (6): 408. 1907. (House 1907b: 408)

Type.

MEXICO. Chihuahua, C.G. Pringle 340 (holotype US00111439, isotypes BM, F, GH, K, LIL, NY, RSA).

Description.

Perennial herb to 50 cm, similar in general habit to I. longifolia, stem softly pubescent. Leaves shortly petiolate, 4-8 × 1.5-2.5 cm, ovate or ovate-elliptic, acute, base cuneate, softly pubescent on both surfaces; petioles 2-5 mm. Flowers solitary, axillary, long-pedunculate; peduncles 2-3.5 cm, pubescent; bracteoles caducous, not seen; pedicels 9-13 mm, pubescent; sepals slightly unequal, outer 6-8 mm, oblong-ovate, obtuse, pubescent, inner 9-11 mm, oblong-elliptic with scarious glabrous margins; corolla c. 6 cm long, funnel-shaped, glabrous, pink, limb 3.5 cm diam. Capsules 13-15 × 10 mm, ovoid with a persistent style, glabrous; seeds 9-10 × 4-5 mm, blackish, minutely puberulent and with long white marginal hairs, c. 10 mm long.

Distribution.

Endemic to northern Mexico where it appears to be rare in rocky grassland.

MEXICO. Chihuahua: near Mapula, F. Shreve 9060 (ARIZ); Sierra Mapula, Rancho Picacho, E. Lehto et al. 21586 (MEXU); Presa Chihuahua, N of El Fresno, M. Fishbein et al. 7383 (ARIZ).

Note.

This species differs from other erect species with ovate-elliptic leaves from Mexico in its hirsute vegetative parts.