Lamourouxia, Kunth, 1817

Francisco-Gutiérrez, Antonio, Ruiz-Sanchez, Eduardo, González, Dolores & Lira-Noriega, Andrés, 2023, Lamourouxia (Orobanchaceae) of Mexico, Phytotaxa 582 (1), pp. 1921-1935 : 1921-1935

Morphological keys based on reproductive characters for Lamourouxia sections present in Mexico (adapted from Ernst 1972)

1. Stamens almost equal in shape and length raising the apex of the corolla; four anthers fertile and similar in size, connivent near the apex of the corolla or exserted........................................................................................................................... Section Lamourouxia

- Stamens strongly unequal, one pair of filaments near the apex of the corolla and other pair shorter near the half of the length of the corolla; two large anthers fertile near the apex of the corolla, two smaller included anthers rudimentary, fertile or sterile, deeply included or absent...............................................................................................................................................................................2

2. Fertile anthers four, the smaller pair rarely sterile.............................................................................................. Section Hemispadon

- Fertile anthers two, the smaller pair rarely fertile or absent................................................................................ Section Adelphidion

Morphological keys based on vegetative and reproductive characters to the Lamourouxia species present in Mexico

Section Adelphidion

Section with four species with disjunct distribution. Two species distributed in Colombia, Ecuador, and Peru. Two endemic species from central Mexico:

1. Leaves linear to subulate, margin entire or minutely incised; calyx with black or brown dots on surface; calyx lobes with margin entire................................................................................................................................................................................ L. dasyantha

- Leaves ovate, margin dentate; calyx without dots on surface; calyx lobes with margin dentate ................................ L. brachyantha

Section Hemispadon

Section with 15 species distributed from northern Mexico to Panama. 14 species are distributed in Mexico, 11 of them are endemic.

1. Plants with inflorescences reclined and inverted flowers.................................................................................................... L. barbata

- Plants with inflorescences erect and flowers not inverted..................................................................................................................2

2. Calyx lobes with margin dentate ............................................................................................................................... L. rhinanthifolia

- Calyx lobes with margin entire...........................................................................................................................................................3

3. Leaves coriaceous or strongly coriaceous ..........................................................................................................................................4

- Leaves membranous or papyraceous..................................................................................................................................................5

4. Leaves pilose, non-glandular........................................................................................................................................... L. avendanoi

- Leaves glandular-tomentose................................................................................................................................................. L. viscosa

5. Leaves 29–38 mm width ....................................................................................................................................................... L. smithii

- Leaves 2–25 mm width ......................................................................................................................................................................6

6. Pedicels claviform ............................................................................................................................................................... L. gracilis

- Pedicels slender ..................................................................................................................................................................................7

7. Leaves with margin entire ............................................................................................................................................. L. integerrima

- Leaves with margin crenate to dentate or serrate ...............................................................................................................................8

8. Calyx lobes 10–12 mm long; lobes of the lower lip of the corolla 4.3–9 mm long.......................................................... L. jaliscana

- Calyx lobes 1–8.2 mm long; lobes of the lower lip of the corolla 1–4 mm long...............................................................................9

9. Calyx tubular ....................................................................................................................................................................................10

- Calyx campanulate ...........................................................................................................................................................................11

10. Leaves with base attenuate to cuneate, one type of bracts along inflorescence .................................................................. L. nelsonii

- Leaves with base truncate, two types of bracts along inflorescence ................................................................................... L. pacifica

11. Leaves 6–10 mm long .................................................................................................................................................. L. microphylla

- Leaves 10–32 mm long ....................................................................................................................................................................12

12. Corolla 26–35 mm long....................................................................................................................................................... L. colimae

- Corolla 40–55 mm long....................................................................................................................................................................13

13. Leaves 3–8 mm width, two types of bracts along inflorescence........................................................................................... L. dispar

- Leaves 1–1.3 mm width, one type of bracts along inflorescence..................................................................................... L. tenuifolia

Section Lamourouxia

Section with 12 species distributed from northern Mexico to Guatemala. 11 species distributed in Mexico, eight of them are endemic.

1. Plants with inflorescences reclined and inverted flowers...................................................................................................................2

- Plants with Inflorescences erect and flowers not inverted .................................................................................................................3

2. Bracts orbicular to broadly elliptic.......................................................................................................................................... L. ovata

- Bracts lanceolate to narrowly rhomboid.......................................................................................................................... L. xalapensis

3. Leaves deeply divided ....................................................................................................................................................... L. multifida

- Leaves entire.......................................................................................................................................................................................4

4. Pedicels 9–21 mm long ......................................................................................................................................................................5

- Pedicels 1–7 mm long ........................................................................................................................................................................6

5. Stems woody, pedicels s-shaped, leaves lanceolate to elliptic ...................................................................................... L. stenoglossa

- Stems herbaceous, pedicels arching forward, leaves broadly ovate............................................................................... L. macrantha

6. Leaves 28–56 mm long, plants restricted to northwestern Mexico................................................................................. L. longiflora

- Leaves 7–25 mm long, plants distributed in central and southern Mexico........................................................................................7

7. Leaves with margin entire o crenulate around the leaf.......................................................................................................................8

- Leaves with margin crenate or dentate only in the upper half of the leaf ..........................................................................................9

8. Leaves and fruits hispidulous non-glandular....................................................................................................................... L. paneroi

- Leaves glandular-pubescent and fruits glabrous ................................................................................................................. L. pringlei

9. Bracts 4–10 mm long, calyx campanulate........................................................................................................................ L. parayana

- Bracts 10–20 mm long, calyx tubular............................................................................................................................... L. zimapana