Trifolium

M. Zohary & D. Heller, The genus Trifolium. 1984R. D. Meikle, Flora of Cyprus 1. 1977
but modified and accepted names differing
1Calyx-tube becoming inflated, papery and conspicuous in fruit
1'Calyx-tube not becoming inflated, papery or conspicuous in fruit
2Perennials with tough rootstocks
2'Annuals
3Inflorescence without a distinct involucre; standard 9-11 mm long
3'Inflorescence with a distinct involucre of small bracts; standard 6-7.5 mm long
4Flower heads globose; calyx teeth longer than tube
4'Flower heads subglobose, ovate to irregularly cylindrical; calyx teeth not longer than tube
5Inflorescence 2-3 cm diam.; corolla not resupinate; seeds verruculose
5'Inflorescence 0.6-1.5 cm diam.; corolla resupinate; seeds smooth
6Fruiting calyx narrowed to apex, subglabrous or thinly hairy, with conspicuous antenna-like calyx-teeth; peduncle equalling or exceeding subtending leaf (rarely shorter); standard 4.5-7 mm long
6'Fruiting calyx subglobose, more or less tomentose, calyx-teeth inconspicuous; peduncle shorter than subtending leaf; standard 3.5-4 mm long
7Perennials
7'Annuals
8Inflorescences sessile, 2.5-3 cm diam.; corolla rosy-purple; plants erect or sprawling, 30-70(-100) cm high
8'Inflorescences long-pedunculate, 1.4-2.5 cm diam.; petals white or tinged pink; plants prostrate, rooting at the nodes
9Inflorescences sessile or subsessile
9'Inflorescences distinctly pedunculate
10Inflorescences densely clustered close to the ground; stem scarcely developed, usually subterranean; small tufted plants usually less then 3 cm high
10'Inflorescences not clustered close to the ground; stems usually well developed, not subterranean
11Inflorescences terminal (pseudo-terminal) with an involucre of enlarged stipule-bracts
11'Inflorescences axillary, without an involucre of enlarged stipule-bracts
12Stipule-bracts suborbicular or broadly ovate; stipules with a short acumen; calyx-teeth about 4 mm long
12'Stipule-bracts broadly ovate with a long cuspidate acumen; stipules elongate-acuminate; calyx-teeth 7-8 mm long
13Inflorescence globose or subglobose; plant glabrous or subglabrous, usually very small; calyx-teeth ovate-acuminate, strongly recurved
13'Inflorescence ovoid, obovoid or oblong; plants pubescent
14Calyx-teeth subulate-sristate, suberect in flower and fruit; lateral veins of leaflets running straight into margin of leaflet or very little curved; claw of standard free
14'Calyx-teeth lanceolate-acuminate, usually recurved in fruit; lateral veins of leaflets curving downwards at apex; claw of standard united with the claws of wings and keel
15Inner flowers of inflorescence sterile, without corollas, accrescent after anthesis; calyx-teeth becoming long and fliform, usually forming a tangled (medusoid) mass concealing the fruits
15'Inner flowers of inflorescence fertile, with corollas; calyx-teeth not tangled or medusoid in fruit
16Peduncle lengthening and recurving after anthesis and burying the inconspicuous infructescence
16'Peduncle not noticeably accrescent; infructescence conspicuous, not buried
17Calyx covering all or most of ripe pod
17'Calyx covering only base to lower third (rarely half) of pod
18Inflorescences terminal (pseudoterminal); fruiting heads often more than 2 cm diam.
18'Inflorescences axillary; fruiting heads usually less than 1 cm diam.
19Upper leaflets narrow, lanceolate, linear or narrowly oblong, at least twice as long as wide
19'All the leaflets orbicular, obcordate, shortly oblong or obcuneate, not narrow
20Uppermost leaves opposite
20'All the leaves alternate
21Inflorescence very large, 2-3 cm (or more) wide; calyx-teeth exceeding corolla
21'Inflorescence smaller, less than 2 cm wide; calyx-teeth shorter than corolla
22Standard 8-10 mm long; calyx-tube glabrous or thinly pilose, distinctly nerved
22'Standard 5-6 mm long; calyx-tube densely pilose, indistinctly nerved
23Corolla very small, about 2-3 mm long, much shorter than the conspicuous, fliform calyx-teeth
23'Corolla 10-13 mm long, usually equalling or exceeding calyx-teeth
24Corolla equalling or almost equalling the sharp-tipped calyx-teeth
24'Corolla exceeding the blunt-tipped calyx-teeth
25Uppermost leaves opposite; inflorescence terminal (pseudoterminal)
25'All the leaves alternate
26Corolla persistent, becoming dry and scarious; wings divaricate; seed with a minutely verruculose testa
26'Corolla deciduous or withering; wings not divaricate; seed with a smooth testa
27Calyx-teeth ovate or oblong, very unequal, strongly accrescent and spreading in fruit
27'Calyx-teeth subulate or fliform, subequal, not markedly accrescent
28Corolla about 2-2.5 cm long; stipules of uppermost (opposite) leaves connate for most of their length
28'Corolla about 1-1.2 cm long; stipules of uppermost (opposite) leaves connate only at base
29Calyx-tube 20-nerved; corolla usually shorter than calyx-teeth or only slightly exceeding it
29'Calyx-tube 10-nerved; corolla distinctly longer than calyx-teeth
30Standard 8-10 mm long; calyx tube glabrous or thinly pilose, distinctly nerved
30'Standard 5-6 mm long; calyx-tube densely pilose, indistinctly nerved
31Inflorescence about 3 cm diam., terminal (pseudoterminal); calyx-teeth 12-15 mm long, conspicuous
31'Inflorescence much less than 3 cm diam., lateral or axillary; calyx-teeth short, inconspicuous
32Flowers white or pale pink, calyx-tube 10-nerved
32'Flowers yellow (rarely mauve, purple or violet), soon becoming dry, brownish and scarious; calyx-tube 5-nerved
33Standard keeled or folded longitudinally over wings and keel; petals yellow
33'Standard flattish or concave, not keeled or longitudinally folded over wings and keel
34Corolla 7-10 mm long
34'Corolla 3.5-5 mm long
35Petals violet or purple, becoming brownish
35'Petals yellow, becoming brown
36Petals at first yellow, later brownish
36'Petals at first violet or mauve, later brownish-yellow or brown