| | 1. Flowers < 8 mm wide, odorless; sepals 1.5–2 mm, ± deciduous; petals 3–6 mm |
| |
| | 2. Leaf blade 8–16 mm, 3–6 mm wide; fruit cylindric, styles persistent; trunks or main stems erect; Desert Mountains |
| FENDLERELLA (no key) |
| | 2' Leaf blade 15–40 mm, 10–30 mm wide; fruit depressed-spheric, styles deciduous; main stems prostrate; n coastal mtns |
| WHIPPLEA (no key) |
| | 1' Flowers generally > 15 mm wide, fragrant; sepals 3–10 mm, persistent; petals 5–25 mm |
| |
| | 3. Stamens 10, alternating long and short; filament base wide, flat; stigma terminal, < 0.5 mm |
| JAMESIA (no key) |
| | 3' Stamens > 20, ± equal, filament base ± linear; stigma linear, elongated along style, > 1 mm |
| |
| | 4. Flowers 3–6 cm wide; leaves 1-veined from base, persistent, leathery; ovary ± superior; petals ± round — c&s Sierra Nevada Foothills (Fresno Co.) |
| CARPENTERIA (no key) |
| | 4' Flowers 1.5–3 cm wide; leaves 3-veined from base, deciduous; ovary partly to completely inferior; petals oblong to elliptic |
| PHILADELPHUS
|