The Ternifolia Group of Macadamia Species 1 
W. B. Storey 2 
The genus Macadamia (family Proteaceae) , 
as presently understood, comprises ten species 
of tropical and subtropical evergreen trees 
(Storey, 1959). One species, M. hildebrandii 
Steenis, is native to Celebes. Three species, 
M. fousselii ( Veill.) Sleumer, M. veillardii 
(Brongn. and Gris.) Sleumer, and M. francii 
( Guill. ) Sleumer, are native to New Caledonia. 
The remaining six species, M. whelani (F. M. 
Bail.) F. M. Bail., M. ternifolia F. MuelL, M. 
integrifolia Maiden and Betche, M. tetraphylla 
L.A.S. Johnson, M. prealta (F. MuelL) F. M. 
Bail., and M. hey ana ( F. M. Bail. ) Sleumer, are 
native to eastern Australia. M. ternifolia is the 
type species upon which von Mueller (1858: 
72) established the genus in 1858. 
The species of Macadamia fall naturally into 
four distinct intrageneric groups. Group 1: 
The three extra-tropical Australian species, M. 
ternifolia, M. integrifolia, and M. tetraphylla. 
Group 2: The two extra- tropical Australian 
species, M. prealta and M. heyana. These species 
were considered by early botanists to belong to 
the allied genus Helicia. Group 3: The two 
tropical species of northeastern Queensland and 
Celebes, M. whelani and Af. hildebrandii, re- 
spectively. Group 4: The three tropical New 
Caledonian species, M. rousselii, M. vieillardii, 
and M. francii. Until they were transferred to 
Macadamia by Sleumer (1955:4-5) in 1955, 
these species had been placed in the genus 
Roup ala. 
Regardless of how the members of the three 
latter groups have been placed generically, there 
seems to have been no question about their 
identities as clear-cut, easily recognized species. 
The identities and typifications of the three spe- 
cies comprising Group 1, however, seem to 
have become confused almost immediately after 
1 Paper No. 1623, University of California, Citrus 
Research Center and Agricultural Experiment Station, 
Riverside, California. Manuscript received April 7, 
1964. 
2 Department of Horticultural Science. 
von Mueller established the genus Macadamia, 
with the collection of additional material by 
various botanists, all of which ended up in 
herbariums as M. ternifolia. The first break in 
this confusion came with the realization by 
Johnson (1954:15-18) that the species which, 
as M. ternifolia, as early as 1870 (Anonymous, 
1870:1811) had been brought into cultivation 
in Australia for its edible nuts, was not von 
Mueller’s M. ternifolia at all but, instead, was 
a species which had never been properly de- 
scribed botanically. Consequently, Johnson de- 
scribed it as a new species, M. tetraphylla. 
The second break came in 1956 when Smith 
(1956:39-40) recognized that the species 
which Maiden and Betche (1897:624) de- 
scribed as a new species, M. integrifolia, but 
which later they revised (Maiden and Betche, 
1899:150) to M. ternifolia var. integrifolia, 
was indeed a valid species in its own right. At 
the same time, Smith clearly typified M. terni- 
folia. In so doing he pointed out that the spe- 
cies described as M. minor and M. lowii by 
F. M. Bailey (1910:11; 1911:127) are only 
variant forms of M. ternifolia, and that the 
names, therefore, must lapse into synonymy. 
In view of the confusion which existed in 
the past, and which continues to some extent 
today, especially in horticultural literature, I 
shall summarize and compare here the salient 
features of the three species in question, with 
the hope that this will clarify the delineations 
which separate the taxons of this so-called 
ternifolia group. 
TYPIFICATION 
The principal taxonomic characters of the 
three species under discussion are listed in Ta- 
ble 1. Additional notes are given below. 
M. ternifolia 
vernacular NAMES: Gympie nut; Maroo- 
chy nut; small-fruited Queensland nut. 
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