1. Arenaria serpyllifolia L., Sp. Pl. 423. 1753. Boiss., Fl. Or. 1:701.1867; Edgew. & Hook. f. in Hook. f., l.c. 239. 1847; Blatter & Fernandez in J. Bomb. Nat. Hist. Soc. 36(4):959. 1933; Schischk. in Kom. l.c. 539; Mizushima in Kitam., Fl. Afghan. 47. 1960 & in Fl. Pl. W. Pak. & Afghan. 47. 1964; Stewart in Pak. J. For. 17(4):484. 1967 & in Biol. 13(2): 60. 1967 & in Ann. Cat. Vasc. Pl. W. Pak. & Kashm. 239. 1972; McNeill in Davis, Fl. Turk. 2:28. 1967.
SHAHINA A. GHAZANFAR & YASIN J. NASIR
Annual, 7-25 cm, with ascending to decumbent stems. Stems branching profusely, slender, scabrid, with or without glandular hairs or glabrous; sometimes glandular-scabrid above, glabrous or scabrid below. Leaves 3-7 x 2-5 mm, usually withering at anthesis, ovate to ovate-elliptic, the lower usually obovate or spathulate, scabrid, ± glandular or glabrous, acute or obtuse, 1-3 (-7) -veined, sometimes the veins scabrid. Inflorescence laxly dichasial or frequently monachasial. Bracts herbaceous, ovate. Pedicels slender, longer than the sepals. Sepals 3.5-4 mm, lanceolate, acute to acuminate, scabrid, ± glandular or glabrous, margin scarious, usually 3-veined. Petals white, less than the length of the sepals. Capsule exceeding the sepals, usually rounded and thickened at the base, narrow above (flask-shaped). Seeds with tubercles at the back.
Fl. Per.: In the plains March-April; at higher altitudes, July-September.
Syntypes: Herb. Burser xiv: 73 (UPS); Hb. Linn 585.14 (LINN); Herb. Clifford 173 (BM).
Distribution: Eurasia (temperate); N.W. Africa (mountainous part), Arabia & Ethiopia; introduced in America.
Common more or less throughout Pakistan. Arenaria serpyllifolia is very similar to the following 3 species described next and often difficult to separate satisfactorily.) Variable in its vegetative characters, especially the indument. A. serpyllilfolia is a tetraploid (2n=40) and probably derived from A. leptoclados (a diploid) and another closely related species (McNeill, l.c. 1967).