Cerastium L.

9. Cerastium L. View in CoL 3

Herbs, sometimes slightly w oody at base, usually hairy. Flowers usually in cymose inflorescences, sometimes solitary. Sepals free; petals white, usually bifid o r em arginate, sometimes absent; stamens 5-10, rarely fewer; nectaries present; styles usually 5, opposite the sepals, sometimes 3, 4 o r 6. F ru it a cylindrical or oblong capsule, often m ore or less curved, dehiscing with twice as m any teeth as styles. Seeds num erous, spherical or reniform. Literature: A. Buschmann, Feddes Reperì. 43: 118-43 (1938). H. Gartner , Feddes Repert. (Beih.) 113: 1-96 (1939). E. Hultén, Svensk Bot. Tidskr. 50: 411-95 (1956). A. Lonsing, Feddes Repert. 46: 139-65 (1939). W. Moschi, Feddes Repert. 41: 153- 63 (1936). W. Moschi, Agron. Lusit. 13: 23-66 (1951).

1 Styles 3, 4, or 6; capsule-teeth 6, 8 or 12 2 Petals shorter than sepals 49. diffusum 2 Petals lf -2 times as long as sepals 3 Stem decumbent or ascending, glabrous except for a line of eglandular hairs down each internode 1. cerastoides 3 Stem erect, covered with minute viscid glands 2. dubium 1 Styles 5; capsule-teeth 10 4 Perennial, often with short non-flowering branches in the axils of leaves 5 Petals usually not more than 1 | times as long as sepals 6 Capsule conspicuously curved; at least the upper bracts usually with scarious margins 7 Lower cauline leaves petiolate 37. sylvaticum 7 Leaves sessile 38. fontanum 6 Capsule straight; bracts without scarious margins 8 Leaves usually 50-80 mm 4. dahuricum 8 Leaves usually not more than 20 mm 9 Petals ciliate at base; peduncles usually not more than 20 mm 30. pyrenaicum 9 Petals not ciliate; peduncles usually more than 20 mm 10 Sepals 5-7 mm, with narrow scarious margins 32. pedunculatum 10 Sepals 7-8 mm, with wide scarious margins 31. runemarkii 5 Petals at least twice as long as sepals 11 Plant with long, soft hairs (sometimes on stems and young leaves only) 12 Plant densely white- to yellow-tomentose to lanate 13 Ovary hairy; leaves 0-5-1-5 mm wide 8. grandiflorum 13 Ovary glabrous; leaves usually more than 1-5 mm wide 14 Plant with branched hairs 9. candidissimum 14 Plant without branched hairs 15 Capsule-teeth with revolute margins 11. tomentosum

15 Capsule-teeth with flat margins 10. biebersteinii 12 Plant not densely tomentose, greyish or greenish

16 Leaves less than three times as long as wide

17 Plant tall, laxly caespitose, flowers many; bracts and sepals obtuse 12. moesiacum 17 Plant mat-forming; flowers 1-5; bracts and sepals acute

26. alpinum 16 Leaves at least three times as long as wide

18 Leaves of flowering stems sparsely ciliate at margins,

surfaces glabrous or nearly so; midrib thin 15. lineare 18 Leaves tomentose and/or glandular, with soft hairs at least at margins; midrib strong and prominent beneath

19 Capsule twice as i ong as sepals 16. gibraltaricum 19 Capsule as long as or slightly longer than sepals

20 Seeds 1 -1-3 mm, strongly tuberculate 13. decalvans 20 Seeds 1 -5-2 mm, rugose 14. boissieri 11 Plant pubescent, glandular or glabrous, but never with long soft hairs

21 Floweringstemswithnon-floweringaxillaryshootsor conspicuous buds

22 Fruiting pedicel curved just beneath the calyx; capsule curved

23 Sepals 5-8 mm; leaves mostly more than three times as long as wide 22. arvense 23 Sepals 3-5 mm; leaves up to three times as long as wide

24 Petals up to 2| times as long as sepals 23. alsinifolium 24 Petals not more than twice as long as sepals

24. jenisejense 22 Fruiting pedicel and capsule straight

25 Bracts ciliate from base to apex

26 Leaves usually at least 4 mm wide 20. scaranii 26 Leaves less than 4 mm wide 19. soleirolii 25 Bracts not ciliate or only ciliate at base

27 Young stems glabrous except for a line of small hairs down each internode; leaves pale green, somewhat fleshy 1. cerastoides 27 Young stems hairy all round, at least above; leaves dark to greyish-green, firm

28 Leaves 20-35 x 6-10 mm; seeds c. 0- 6 mm (Açores)

21. vagans 28 Leaves linear to linear-lanceolate, up to 5 mm wide;

seeds more than 1 mm

29 Bracts pubescent, with wide, scarious margins

17. banaticum 29 Bracts glabrous or nearly so, lowest herbaceous,

upper with narrow scarious margins 18. julicum 21 No non-flowering axillary shoots or buds on flowering stems

30 Bracts leaf-like, without scarious margins

31 Glaucous-pruinose; stems up to 100 cm; leaves usually

50-80 mm (N.E. Russia, lowland) 4. dahuricum 31 Not pruinose; stems up to 15 cm; leaves up to 30 mm

32 Leaves of at least the non-flowering shoots obovate to spathulate, widest in the upper half, or suborbicular

33 Seeds 1-1-5 mm, testa close 27. arcticum 33 Seeds 1 -5-2 mm, testa loose 28. uniflorum 32 Leaves ovate to elliptical, widest in the middle or below the middle, acute

34 Seeds 1 -3-1-7 mm 34. carinthiacum 34 Seeds 1 -7-2-5 mm 29. latifoiium 30 Atleast upper bracts sepal-like or minute, with scarious margins

35 Sepals 7-10 mm

36 Plant glabrous; leaves up to 20 mm 26. alpinum 36 Plant pubescent; leaves 20-80 mm

37 Inflorescence umbel-like; pedicels mostly shorter than sepals 3. maximum 37 Inflorescence a wide-spreading cyme; pedicels much longer than sepals 35. transsiivanicum 35 Sepals 2-6 mm

38 Leaves usually 30-70 mm 39 Capsule-teeth revolute 39. pauciflorum

39 Capsule-teeth erect

40 Leaves sessile 36. subtriflorum

40 Lower cauline leaves petiolate 37. sylvaticum

38 Leaves usually not more than 20 mm

41 Pulvinate, propagating by means of bulbil-like terminal buds (Arctic) 25. regelii

41 Bulbil-like terminal buds absent

42 Leafy stolons absent

43 Seeds squamose 33. dinaricum

43 Seeds with low tubercles 34. carinthiacum

42 Leafy stolons present

44 All bracts with scarious margins 22. arvense

44 Lowest bracts herbaceous

45 Leaves usually not more than 5 mm wide; seeds finely tuberculate 23. alsinifolium

45 Leaves usually more than 5 mm wide; seeds strongly tuberculate 36. subtriflorum

4 Annual, neverwithshortnon-floweringbranchesintheaxils of leaves

46 Plant glabrous 47 Cauline leaves connate 6. perfoliatum 47 Cauline leaves not connate 47. seinidecandrum 46 Plant hairy 48 Pedicels with deflexed-appressed eglandular hairs, without glandular hairs

49 Sepals with eglandular hairs protruding well beyond apex 40. illyricum

49 Sepals without eglandular hairs protruding beyond apex

50 Pedicels 8-15 mm; petals ±equalling sepals 40. illyricum

50 Pedicels 10-70 mm; petals longer than sepals

51 Sepals 4-5- 5 mm 42. scaposum

51 Sepals 8-9- 5 mm 41. pedunculare

48 Pedicels without deflexed-appressed eglandular hairs, with or without glandular hairs

52 Sepals with eglandular hairs protruding well beyond apex

53 Pedicels shorter than sepals; flowers in dense clusters

44. glomeratum

53 Pedicels longer than sepals; flowers in open dichasia

54 Sepals 10-11 mm 40. illyricum

54 Sepals 3-6- 5 mm 43. brachypetalum

52 Sepals without eglandular hairs protruding beyond apex

55 Petals ciliate at base

56 Sepals with eglandular and glandular hairs 45. rectum

56 Sepals with eglandular hairs only 5. nemorale

55 Petals glabrous

57 Pedicels shorter than sepals; flowers clustered

58 Sepals with eglandular hairs 50. siculum

58 Sepals without eglandular hairs

59 Sepals 3 -5-9 mm; capsule 15 mm or less 51. gracile

59 Sepals 9-12 mm; capsule more than 15 mm

7. dichotomum

57 Pedicels longer than sepals; flowers in open dichasia

60 Bracts with scarious margin

61 Upper bracts scarious at least in upper |

47. semidecandrum

61 Bracts scarious at most in upper |

62 Leaves 12-27 mm; plant up to 22 cm; petals at least

14 times as long as sepals 46. ligusticum

62 Leaves 4-15 mm; plant not more than 14 cm; petals not more than 1 $ times as long as sepals.

48. pumilum

60 Bracts completely herbaceous

63 Sepals glandular-hairy, without eglandular hairs

64 Petals l |- 2 times as long as sepals 46. ligusticum

64 Petals shorter than to slightly longer than sepals

51. gracile

63 Sepals with eglandular as well as glandular hairs

65 Petals shorter than sepals 49. diffusum

65 Petals longer than sepals 46. ligusticum