Jaffré, Tanguy

Pintaud, Jean-Christophe

Horizon / Pleins textes

IHD Nournèa 1 8 SEP. 2002 
IIÏÎÏIÏÏÜII South African Journal of Science 97, November/December 2001 Serpentine Ecology 
020016745 
Patterns of dlversity and 
endemism in palms on 
ultramafic rocks in New 
Caledonia 
Jean-Christophe Pintaud' and Tanguy Jaffré'1 
Several factors can explain the high diversity and endemism of New 
Caledonian palms on ultramafic rocks. A geographical pattern can 
be recognized, with many species occurring on the extensive and 
continuous ultramafic outcrop of the southern part of New Caledo· 
nia, and other species endemie to isolated ultramafic mountain-
tops. ln these cases, a substrate effect may be difficult to distin-
guish from the geographical effect, si nee a similar pattern of diver-
sity and endemism occurs on schistose rocks, and seems to be 
linked to Pleistocene refugia. However, a morphological or physio-
logical specialization in relation to the ultramafic substrate can be 
identified in severa! species. Adaptive radiation on ultramafic rocks 
occurs in the genus Burretlokentla, whlch includes several closely 
related species restricted to very small areas and growing on the 
most selective, hypermagnesian soils. One species, Campecarpus 
fulcitus (Brongn.) Wendl. ex Beee., is a stilt-rooted palm growing 
only in rocky peridotitic habitats. Another pattern is represented by 
species widespread on the island but restricted to ultramaflc rocks. 
These species otten have a wide ecological range (growing on very 
diverse soil types, both in rainforest and maquis, at different eleva-
tions) and are more likely to be competitively excluded from other 
substrates rather than really requiring ultramafic rocks for their 
growth. Pa lm diversity and endemism on ultramafic rocks is the re-
suit of severa! factors related to the history and ecology of the ultra-
matie environment as a whole and not only or not directly to the 
peculiar edaphic conditions. 
Introduction 
The influence of ultramafic rocks on species richness, floristic 
composition and endemism in New Caledonia has been dis-
cussed by Virot,' Jaffré2 and Schmid3 and more specifically for 
'maquis' vegetation by Morat et al.' and for the rainforests by 
Jaffré et al.' There are, however, few studies thal discuss the role 
of ultramafic substrates in specifie taxa from a phylogenetic per-
spective. The most significant study on this aspect is that of 
Setoguchi et a/.0 on the Araucariaceae. 
ln this article, we discuss the distribution pattern of palms 
growing on ultramafic rocks. The New Caledonian palms com-
prise 37 species, ali endemie to the island and belonging to 16 
genera, of which 15 are also endemic.7~9 Palms are distributed 
throughout the main island but almost exclusively in rainforests 
Fig. 1), with a peak of endemism and diversity in the south and 
northeast (Table 1 ). 
These palms represent three evolutionary lineages. Pritchard-
iopsis is a monotypic genus belonging to the ancient and unspe-
cialized subfamily Corphoideae and is restricted to a single 
loGJ\ion on ultramafic rocks. ln subf<Jmily Arecoideile, tribe 
Areceae, there are two weil diversified monophyletic groups, 
'!RD. Laboratoire de Bolanrque el d'Ecologie Appliquée. Centre de Nouméa, BP A5, 
98848 Nouméa Cedex. New Caledonia. 
0 1Author lor corresponde nee. E-marl. tanguy.jaHre@noumea.ird.nc 
N 
Ill On c•~us roeb 
a On uttramafic rocks 
- On acldk: rocks 
-·· Bound•ry ot phytoveogn~phleal seçtors 
JOWEA 
< 
o,. 
.. 
<_. 
LIFOU 
... MARE 
' .. ~ < ..... <> .. 
SOUTH 
l\g lie des Pins 
Fig. 1. Distribution of rainforests and phytogeographical units in New Caledonia. 
one in subtribe Archontophoenicinae, including three genera 
and eight species and the other in the Iguanurinae, with 12 
genera and 28 species.10'11 These arecoid palms are weil repre-
sented on both ultramafic and schistose rocks. We base our 
study on a comparison between the distribution and phylogeny 
of the species (Figs 2 and 3). 
Materials and methods 
Phylogenetic data come from two cladistic analyses, of 
subtribes Archontophoenicinae10 and lguanurinae,11 based on 
morphological and anatomical characters. Distribution data for 
each species over ils range were compiled by Pin taud et a/. 12 and 
are presented here as Figs 2 and 3. 
Results 
The distribution of palms is strongly linked to the nature of the 
substrate. Fifteen species are restricted to ultramafic rocks, 13 to 
schists and one to corallimestone. Only eight species occur on 
both schistose and ultramafic rocks (Table 2). 
Within the Archontophoenicinae, three species are restricted 
to ultramafic rocks, four to schistose rocks and only one is 
present on both substrates. The genus Actinokentia is confined to 
ultramafic rocks, with one species, A. divaricata (Brong & Gris) 
Vieill., widespread in the southern and central parts of the 
island, and another, A. huer/imannii H. Moore, with very local 
distribution in the south. The genus Chambeyronia contains one 
species apparently indifferent to the substrate and one restricted 
to sc his tose rocks in the northeast. The genus Kentiopsis indu des 
Table 1. Distribution of palms within the phytogeographical sectors (see Fig. 1 ). 
Se ct ors Genera Endemie Species Endemie 
genera species 
Northeast 11 4 17 9 
Northwest 2 0 2 Total centre: 0 Total centre: 
Central-west 8 0 16 18 2 4 
Central-east 7 0 16 0 
South 10 19 8 
Table 2. Distribution of palm species on the three main substrate types. 
Substrate Genera Species 
Ultramafic rocks only 3 15 
Schists only 4 13 
Limestone only 0 1 
8oth ultramafic rocks and schists 8 8 
Serpentine Ecology South African Journal of Science 97, November/December 2001 549 
four species, with only one growing 
on ultramafic rocks (Fig. 2). 
Within the lguanurinae, the spe-
cies are almost equally dis tribu ted on 
both substrates, except in Basselinia 
section Basselinia (numbers 18-21 in 
Fig. 3) and in Burretiokentia (numbers 
29-33), Iwo groups clearly more di-
versified on ultramafic rocks. 
The only coryphoid palm, Prit-
chardiopsis jeanneneyi Beee., has a sin-
gle locality on ultramafic rocks in the 
south (Fig. 2). 
Discussion 
The mere documentation of the 
number of species restricted to each 
type of substrate and growing on 
severa! (Table 2), gives little informa-
tion about how the species distribu-
tions are linked to substrate.lndeed, 
there are Iwo major centres of diver-
sity and endemism in New Caledo-
nia - one in the northeast and the 
other in the south. The northeastern 
part is entirely schistose and the 
southern partis completely covered 
with peridotites, so the 17 species en-
demie to these sectors (half of the 
palm flora) are obviously restricted 
to a single type of substrate. This bi-
polar distribution is most probably 
related to climatic fluctuations 
during the Pleistocene, since low-
land rainforest is likely to have per-
sisted only in the northeast and 
south during the dry period.n·13 
Montane forest refugia may also 
have existed in the central part of 
the island, accounting for local 
endemism on either ultramafic or 
schistose rocks. 
This geographical pattern is illus-
trated by the closely related mono-
typic genera Veillonia and Campe-
carpus (Fig. 4), the former being re-
stricted to the northeast on schist 
and the latter to the south on ultra-
mafic rocks. However, Campecarpus 
fulcitus (Brong. & Gris) Wendl. ex 
Beee. is restricted to a particular type 
of habitat - rocky, unstable 
peridotitic slopes - where it is able 
to become established and grow by 
means of ils long stilt roots. These 
roots hold the trunk above the rocks 
<md reach the soi] in crevices and 
cr<1cks betwc·en the boulders (Fig. 5). 
The distribution of this species is 
therefore determined by both geo-
graphical (historical) and ecological 
f<1ctors. 
Another distribution pattern is 
representcd bv species widespreild 
SUBSTRATE SECTORS 
UR AR S CWCE NE NW 
" R 
c 
H 
0 
N 
T 
1. AcUnokenlia 
dlvarlcata 
2. Actinokentia 
huerlimannll 
f------- 3. ~:;:~:yronia 
..u..+------- 4. Chambeyron/a 
macrocarpa 
Livlstoninae 
7. Kentlopsls 
magniflca 
8. Kentlopsls 
pyrlformls 
9. Prltchardlopsls 
}eanneneyl 
Il species present on ultramafic rocks 
~ s.pecies present on acîdtc rocks 
Il species present in the corresponding condition 
Fig. 2. Phylogeny anet ecological range of the New Caleclonian Archontophoenicinae (and Livistoninae). Substrate: 
UR, growing on ultramafic rocks; AR, growing on acidic rocks; sectors: see Fig. 1; blank, species absent. 
10. Alloschmidi11 
glabrata 
11. Lavoixia 
macrocarpa 
12. Clinosperms 
bracteale 
13. Brongniartikentia 
lanuginu:sa 
14. Brongniarlikentia 
vaginaiQ 
1 S. Cyphokentia 
macrostachya 
16. Moratia 
ceri fera 
17. Cyphosperma 
balansae 
J 8. Basulinia 
pancheri 
19. Basse/inia 
gracilis 
20. Bas:se/inia 
vestita 
21. Basselinia 
Jeplanchei 
22. Basse/ini11 
humboldtiana 
23. Basselinia 
prophyrea 
24. Bas:selinia 
tomentosa 
25. Basselinia 
ile rata 
26. Basse/inia 
Javieri 
27. Banelinia 
velu tina 
28. Basselinia 
.wrdida 
29. Burretiokentia 
hapala 
30. Burretiokentia 
••ieillurdii 
31. Burretiokentia 
grandijloru 
32. Buruliolt.enlia 
Jumasii 
33. Burretiokentiu 
koghiensü 
34. Cyphophoeni.x 
eleguns 
35. Cyphophorni~ 
1111crlr 
16. Camprcarpu5 
fu/ci tus 
:n. Vril/onia 
alba 
SUBSTRATE SECTORS 
UR AR S CW CE NE NW 
Fig. 3. Phylogeny and ecological range of the New Caledonian lguanurinae. Legend as in Fig. 2. 
550 South African Journal of Science 97, November/December 2001 Serpentine Ecology 
MARE 
~ 
• Veillonia alba 
• Campecarpus fulcffus 
0 ULTRAMAFIC ROCKS 
- Boundary of phytogeographlcal units 
Fig. 4. Example of bipolar distribution of sister taxa, Campecarpus fulcitus on 
ultramafic rocks in the south and Veillonia alba on schist in the northeast (see 
Fig. 3, numbers 36-37). 
on the island (and therefore potentially dispersed on various 
substrates), but restricted to ultramafic rocks. This is illustrated 
by Iwo genera essentially diversified on ultramafic rocks, 
Actinokentia (Fig. 2) and Basselinia, especially in the section 
Basselinia (Fig. 3, numbers 18-21). Actinokentia has two species, 
which grow on! y on ultramafic rocks. One is very localized in the 
southem sector and the other, Actinokentia divaricata, is very 
common and widespread in the southern and central parts of 
the island. In section Basselinia, one species is ubiquitous 
(B. gracilis (Brong. & Gris) Vieill.), one is restricted to an ultra-
mafic mountain-top in the central region (B. vestita H. Moore), 
and two are widespread but restricted to ultramafic rocks -
B. deplanchei (Brongn. & Gris) Vieill. has almost the same distri-
bution as Actinokentia divaricata and B. pancheri (Brong. & Gris) 
Vieil!. is found throughout the island on most ultramafic out-
crops (Fig. 6). These three species not only share the sa me dis tri-
\, 
~ B61ep 
OUVE A 
J <75ou 
MARE 
N 
'(J 
• BassefmJa p<mchen 
0 Ul TRAMAFIC ROCKS 
- Boundary of phytogeographical un·rts 
~lie des Pins 
\. 11)(• 
~llnBélep 
N 
0 ULTRAMAFIC ROCKS 
0~~~50km 
bution pattern, but also ecological similarities: they are pioneer 
species, abundant in secondary forest, with a broad ecological 
range on ultramafic rocks. It is likely thal these species are absent 
from other substrates because they are competitively excluded 
from them rather than because of mineral nutrition. 
A different pattern of diversity is represented by Burretiokentia, 
a genus of five species (Fig. 3, numbers 29-33), four of which 
grow on ultramafic rocks. Three of these species (B. grandijlora 
Pintaud & Hodel, B. dumasii Pintaud & Hodel and B. koghiensis 
Pintaud & Hodel) forma monophyletic group, are very localized 
(Fig. 7), and restricted to brown hypermagnesian soils derived 
from serpentine. It is likely th at this clade represents an adaptive 
radiation on this peculiar, very distinctive type of soi!, where 
nickel hyperaccumulators are also found. 
It appears therefore that soils derived from ultramafic rocks 
indu ce sorne specializations and radiations, but sorne endemism 
on this substrate is also partly due to factors unrelated to the 
edaphic conditions. 
1. Virot R. (1956). La végétation canaque. Thesis, University of Paris. 
2. Jaffré T (1980). Etude écologique du peuplement végi'tal des sols dérivés de roches 
ultrabasiques en Nouvelle-Calédome. Travaux et Documents de I'ORSTOM, no. 
124. 
3. Schmid M. (1982). Endémisme et spéciation en Nouvelle-Calédonie. CR. Soc. 
Biogéogr 58, 52-60. 
4. Morat P, ]affré T, Veillon ].M. and MacKee, H.S. (1986). Affinités floris tiques et 
considérations sur l'origine des maquis miniers de la Nouvelle-Calédonie. Bull. 
Mus. Nat/. Hist. Nat., Paris, 4 ème sér., 8, section B, Adansonia, no. 2, 133--182. 
5. Jaffré T, Veillon ]-M. and Pintaud J-C. (1997). Comparaison de la diversité 
floristique des forêts denses humides sur roches ultramafiques et sur substrats 
différents en Nouvelle-Calédonie. ln Ecologie des Milieux sur Roches 
Ultramafiques et sur Sols Métallifères, eds T ]affré, R.D. Reeves and T Becquer, 
pp. 163--170. Documents scientifiques et techniques, 1112, volume spécial, 
ORSTOM Nouméa. 
6. Setoguchi H., Asakawa Osawa T, Pintaud J-C., Jaffré T and Veillon ]-M. (1998). 
Phylogenetic relationships within Araucariaceae based on rbcL gene se-
quences. Am.]. Bot. 85,507-1516. 
7. Moore HE. and Uhl N.W (1984). The indigenous palms of New Caledonia. 
Allertonia 3, 313--402. 
8. Pintaud]-C. and Hodel D.R. (1998). A revision of Kentiopsis, a genus endemie to 
New Caledonia. Principes 42,32-33,41-53. 
9. Pintaud J-C. and Hodel D.R. (1998). Three new species of Burretiokmtia. 
Principes 42, 152-155, 160-166. 
10. Pin taud j-C. (1999). A cladistic analysis of the Archontophoenicinae (Palmae: 
AreceJe) based on morphological and ,U1atomicol charocters. A1em. New York 
Bot_ Gard. 83, 279-284. 
11. Fintaud j-C. (1999). Phylogénie, biogéographie c·t écolo,c;ie des polmters de 
NouvPlle-CalédoniP. The."is, Universitv of Toulousp 
12. l'in taud ]-C., Jaffré T. and \'eillon ]-M. (2001 ). Consen·ation slatus of New Col-
edonia palms. Pacifie (OIN'n'. Biol. 5, 9-15. 
13. Jaffré T and Veillon ]-M. 1995. Structurol and floristic ch.u.1cteristics of a rain-
forest un schist in New Caledonia: a cnmpari.son \vith an ultrdmafic rainforest. 
Bull. A.Jus. Nat! 1 list. Nat, Paris, -1 ème sèr., 17, ~ection B., Adan.:;onin, no~ 3-4, 
201-226. 


Patterns of diversity and endemism in palms on ultramafic rocks in New Caledonia

Abstract

Similar works

Full text

Available Versions

Horizon / Pleins textes

Name not available