Leichhardtia

Gâteblé, Gildas, Meve, Ulrich & Liede-Schumann, Sigrid, 2023, A new threatened New Caledonian Leichhardtia (Apocynaceae, Asclepiadoideae, Marsdenieae) species discovered from a TV programme and social media, Phytotaxa 591 (2), pp. 91-100 : 98

Key to the species of Leichhardtia of New Caledonica

1. Leaves linear, lanceolate, or very slenderly ovate, usually more than 4× as long as broad ...............................................................2

1’. Leaves ovate, elliptic, obovate or orbicular, usually less than 4× as long as broad ...........................................................................7

2. Plants erect, even apically not twining; leaves caducous, leaving conspicuous scars ...................................................... L. ericoides

2’. Plants ascending, at least apically twining, leaves not caducous .......................................................................................................3

3. Corolla not longer than 3 mm, leaves less than 4 cm long; internodes less than 2 cm long .............................................................4

3’. Corolla more than 3 mm long, leaves more than 6 cm long; internodes more than 3 cm long..........................................................5

4. Corolla greenish-yellow, campanulate, tube around 1/3 of total corolla length....................................................... L. neocaledonica

4´. Corolla whitish, narrowly urceolate, tube ovoid to tubular, at least 1/2 as long as total corolla length................................. L. weari

5. Leaves more than 0.5 mm wide; inflorescences distinctly bostrychoid (check for scars that fallen pedicels left); floral buds cylindrical; corolla lobes not ciliate ............................................................................................................................ L. mackeeorum

5’. Leaves less than 0.5 mm wide; inflorescences sciadioidal; floral buds conical or cylindrical; corolla lobes ciliate or not ..............6

6. Shoots glabrous; inflorescences sessile; floral buds conical, corolla lobes not ciliate................................................... L. assimulata

6’. Shoots with an indumentum; inflorescences with at least 5 mm long peduncle; floral buds cylindrical, corolla lobes ciliate ........... ................................................................................................................................................................................. L. neomicrostoma

7. Plants erect, not exceeding 30 cm; leaves suborbicular, abaxially with protruding rhachis ............................................. L. kaalensis

7’ Plants twining, exceeding 30 cm; leaves of various shapes, but not suborbicular, abaxially without protruding rhachis.................8

8. Inflorescences richly branched, di-or monochasially cymose (at least the older ones) .....................................................................9

8’. Inflorescences usually sciadioidal, rarely slightly bostrychoid when old ........................................................................................11

9. Style-head rostrate, conspicuously protruding 4–6 mm long corolla............................................................................ L. paulforsteri

9’. Style-head umbonate or conical, not conspicuously protruding from the less than 4 mm long corolla .........................................10.

10. Leaves less than 4 cm long, less than 3 cm wide, elliptic, basally rounded; corolla lobes with regularly distributed trichomes; corona of free staminal lobes................................................................................................................................... L. guillauminiana

10’. Leaves more than 5 cm long, more than 3 cm wide, ovate, floral buds ovoid; corolla lobes glabrous; corona of free staminal lobes and a wavy ring of connate staminal and interstaminal parts..................................................................................... L. tylophoroides

11. Inflorescences of more than 10 densely packed flowers, corolla brilliant red ......................................................... L. goromotoorum

11´. Inflorescences with less than 10 flowers or flowers not densely packed, flowers of different colours, but never red ....................12

12. Mature buds at least three times longer than wide; corolla at least 10 mm long, radiantly white; style-head elongated-conical ...13

12’. Mature buds less than three times longer than wide; of various colours, at the most with some radiantly white parts; style-head umbonate to conical..........................................................................................................................................................................14

13. Corolla 10–12 mm long ................................................................................................................................................ L. lyonsioides

13’. Corolla 30 mm long or more .............................................................................................................................................. L. speciosa

14. Corolla lobes at the most as long as tube, usually shorter; corolla shape urceolate.........................................................................15

14’. Corolla lobes at least as long as the tube, usually distinctly longer, corolla shape rotate ................................................................18

15. Plants covered with a soft, yellowish indumentum .........................................................................................................................16

15’. Plants (at least stems and leaves) glabrous; if indument present, then not yellowish .....................................................................17

16. Corolla purple red to purple brown, corolla tube more open, not explicitly fleshy or enclosing the corona; staminal corona lobes laminar and longer than broad; plants of Grande Terre.................................................................................................. L. dognyensis

16’. Corolla white to rose; upper rim of the corolla tube fleshy and protruding inwardly to create a suburceolate flower tube shape that strictly encloses the corona; staminal corona lobes protruding, broader than long; plants of Isle des Pins...................... L. kuniensis

17. Leaves> 9°cm long; peduncles and pedicels glabrous; buds almost globose ......................................................... L. koniamboensis

17’. Leaves not exceeding 6 cm length; peduncles and pedicels with indument; buds conical ......................................... L. oubatchensis

18. Flowers at least 10 mm diam., but distinctly fused, adaxially glabrous, but marginally ciliate............................... L. weberlingiana

18’. Flowers not more than 7 mm diam., corolla adaxially with trichomes, but marginally not ciliate..................................................19

19. Corolla> 5 mm diam., purplish-brown; lobes adaxially densely and regularly covered with white trichomes.............. L. nigriflora

19’. Corolla <5 mm diam., yellowish; lobes sparsely pubescent ............................................................................................ L. variifolia