Key to Rubiaceae

View taxon page for Rubiaceae

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Shrub or small tree

2. Inflorescence a dense, spheric 

head 

1. A dense, often spheric inflorescence of sessile or subsessile flowers.
2. In Asteraceae and some other groups, a head-like inflorescence is one in which sessile or subsessile inflorescence units (e.g., heads in Asteraceae, umbels enclosed by involucres in Eriogonum), instead of individual flowers, are attached in a short dense cluster without an evident axis or branches.

, flowers >> 50; fruit 2–4 dry, brown nutlets; leaves not fleshy ..... CEPHALANTHUS

2' Inflorescence a short, compound 

cyme 

1. In flowering plants excluding Asteraceae and some other groups, a branched inflorescence in which the central or uppermost flower opens before the peripheral or lowermost flowers on any axis. see 2. In Asteraceae and some other groups, a cyme-like inflorescence is one in which the central or uppermost inflorescence units (e.g., heads in Asteraceae, umbels enclosed by involucres in Eriogonum), instead of individual flowers, develop and mature before the peripheral or lowermost inflorescence units on any axis.

, flowers 1–5; fruit drupe, orange-red; leaves fleshy ..... [COPROSMA]

1' Annual to subshrub

3. Leaves all 

opposite 

1. Arranged in pairs along an axis - e.g., two leaves per node. 2. Occurring in the same rank, directly above or below, as 'stamens opposite petals'. 3. Located directly across from.

4. Flowers 

sessile 

Without a petiole, peduncle, pedicel, or other kind of stalk.

, 

axillary 

Pertaining to or within an axil, especially a leaf axil.

, 1–many per 

node 

Position on a stem from which one or more structures (especially leaves, buds, branches, or flowers) arise.

..... [DIODIA]

4' Flowers long-pedicelled; inflorescence terminal cyme, open, few-flowered ..... KELLOGGIA

3' Leaves generally 

whorled 

Arranged in groups of three or more at nodes or positions along an axis (e.g., three leaves per node).

5. Inflorescence a dense 

spike 

1. In flowering plants excluding Asteraceae, Cyperaceae, Poaceae, and some other groups, an unbranched inflorescence in which the flowers are sessile and nearly always open from the bottom to the top of the inflorescence. 2. In Asteraceae, Cyperaceae, Poaceae, and some other groups, a spike-like inflorescence is one in which the inflorescence units (e.g., heads in Asteraceae; spikelets in Cyperaceae and Poaceae), instead of individual flowers, are sessile and attached directly to the main axis of the inflorescence, not to branches, and in which floral development may or may not proceed as in 1.

, bracts overlapping; calyx 0 ..... CRUCIANELLA

5' Inflorescence not a spike; calyx present or 0

6. Flowers pedicelled (except Galium murale), in 

panicles 

1. In flowering plants excluding Asteraceae, Cyperaceae, Poaceae, and some other groups, a branched inflorescence in which the basal or lateral flowers (or some of them) open before the terminal or central flowers on any axis. 2. In Asteraceae, Cyperaceae, Poaceae, and some other groups, a panicle-like inflorescence is one in which at least some of the inflorescence units (e.g., heads in Asteraceae; spikelets in Cyperaceae and Poaceae), instead of individual flowers, are attached (stalked or unstalked) to branches and not directly to the main axis of the inflorescence and in which floral development may or may not proceed as in 1.

, clusters of 2–many, occasionally 1; 

involucre 

Group of bracts more or less held together as a unit, subtending a flower, fruit (acorn cup), or inflorescence.

0; calyx 0 ..... GALIUM

6' Flowers sessile, in few-flowered heads; involucre bracts ± free, ± = leaves; calyx 6-lobed ..... SHERARDIA

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