Matricaria L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 165-166

60. Matricaria L. 2

(Tripleurospermum Schultz Bip.)

Herbs. Leaves alternate, irregularly 2- to 3-pinnatisect, with numerous linear segments. Capitula medium, pedunculate. Involucral bracts in several rows, with a scarious margin. Receptacle hemispherical to conical, more or less solid; scales absent. Outer florets usually ligulate, female, white or rarely pink; inner florets tubular, 5-lobed, hermaphrodite, yellow. Achenes more or less compressed laterally, with 3 conspicuous, smooth ribs on the adaxial face and 1-2, rarely more, resin-glands at the apex of the abaxial face; pappus a small corona, sometimes absent.

1 Lateral ribs of achene distinctly longer than the median rib, strongly incurved above; pappus absent

2 Abaxial face of achene pale to medium brown, smooth or weakly rugose; capitula (4-) 10-60 1. trichophylla 2 Abaxial face of achene blackish-brown, strongly rugose; capi-

- tula 3-10 2. conoclinia 1 Lateral ribs of achene about as long as the median rib, not or slightly incurved above; pappus present

3 Ligules less than 0.7 the diameter of the involucre, sometimes absent

4 Ligules present; basal and lower cauline leaves with lobes at base and in distal | only 6. rosella 4 Ligules absent or very short; basal and lower cauline leaves with lobes throughout their length 7. tempskyana 3Ligules at least 0.5 the diameter of the involucre

5 Annual; achene with strongly inflated ribs; pappus c. 0.5 as long as achene, 3-lobed 8. parviflora 5 Ribs of achene not strongly inflated; pappus not more than

0.5 as long as achene, usually truncate

6 Annual; achene with well-separated ribs; resin-glands± orbicular 5. perforata 6 Biennial or perennial; achene with contiguous or slightly separated ribs

7 Flowering stems unbranched; resin-glands of achene± orbicular 3. caucasica 7 Flowering stems usually corymbosely branched above; resin-glands of achene elongated

8 Plant eglandular, usually glabrous; resin-glands of achene

2, longitudinally elongated 4. maritima 8 Plant usually glandular-puberulent; resin-gland of achene

1, transversely elongated 1. trichophylla