Citation: Link, Handb. 2:235 (1831).

Derivation: Greek petra, stone; rhagas, a break; the Greek form of the epithet of the type species, Tunica saxifraga, which was named for a similarity to Saxifraga.

Synonymy: Gypsophila L. sect. Petrorhagia Ser. ex DC., Prod. 1:354 (1824). Including Tunica in part of some authors and Kohlrauschia Kunth.

Common name: None

Description:
Annual herbs, erect, with stiff stems; leaves linear.

Flowers subtended by calyx-like bracts; calyx 5-toothed, 5-angled, and with scarious strips uniting the sepals; petals 5, exceeding the calyx, without coronal scales in the throat; stamens 10; styles 2.

Capsule ovoid or oblong, opening by 4 teeth; seeds dorsiventrally compressed, shield-shaped; embryo straight.

Distribution:  About 20 Mediterranean species.

Biology: No text

Key to Species:

1. Stem predominantly glabrous in the middle region; seeds papillose, less than 1.3 mm long	P. nanteuilii 1.
1. Stem regularly glandular-hairy in the middle region; seeds tuberculate, more than 1.3 mm long	P. velutina 2.

Author: Not yet available