''Carnarvonia araliifolia'', commonly known as the red oak, red silky oak, Caledonian oak or elephant's foot, is the sole species in the genus ''Carnarvonia'', a member of the

Proteaceae The Proteaceae form a family (biology), family of flowering plants predominantly distributed in the Southern Hemisphere. The family comprises 83 genus, genera with about 1,660 known species. Australia and South Africa have the greatest concentr ...

family. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the rainforests of northeastern

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

, Australia.

Description

The red oak is a large tree growing to or more in height, and it may have small rounded

buttress root Buttress roots, also known as plank roots or stilt roots, are large, wide roots on all sides of a shallowly rooted tree. Typically, they are found in nutrient-poor tropical forest soils that may not be very deep. They may prevent the tree from fa ...

s. These may give the lower trunk the appearance of an elephant's foot, and are the source of one of the common names for the species. The trunk bears numerous, closely spaced small

lenticel A lenticel is a porous tissue consisting of cells with large intercellular spaces in the periderm of the secondarily thickened organs and the Bark (botany), bark of woody stems and roots of gymnosperms and dicotyledonous flowering plants. It func ...

s. The large

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

leaves are divided pedately and are highly variable, having anything from 3 to 20 leaflets. They range in size from long, including the

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

. The leaves are arranged alternately on the branches. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is a

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

, produced either terminally, in the

leaf axils A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, fl ...

, or directly from the branches or trunk (the last two cases are known as

ramiflory In plant biology, ramiflory is the production of fruit and flowers on the woody branches of a plant, formed in a previous season. The corresponding condition for the trunk of the plant is known as cauliflory Cauliflory is a botanical term ...

and

cauliflory Cauliflory is a botanical term referring to plants that flower and fruit from their main stems or woody trunks, rather than from new growth and shoots. It is rare in temperate regions but common in tropical forests. There have been several st ...

, respectively). They develop between November and May. The fruit is a woody follicle measuring up to long by wide, with the

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

(stem) attached at one side. They contain one or two winged seeds up to long.

Taxonomy

This species was first described by the German-born Australian botanist

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Victoria, Australia ...

, from a specimen collected by

John Dallachy John Dallachy (c. 1808 – 4 June 1871) was a curator of Melbourne Botanic Gardens and a plant collector. Dallachy was born in Elginshire, Scotland. He worked as a gardener for the Earl of Aberdeen and Kew Gardens. In 1847, he went to Ceylon t ...

in the forested mountains around

Rockingham Bay Rockingham Bay is a bay in Far North Queensland, Australia. The bay opens onto the Coral Sea, part of the South Pacific Ocean. Adjacent to the bay is the Girramay National Park, south of which is the town of Cardwell. Goold Island is a small ...

in Queensland. He published the description in volume 6 of his massive work '' Fragmenta phytographiæ Australiæ'' in 1867. In 1995 the Australian botanist

Bernard Hyland Bernard Hyland (Bernard Patrick Matthew Hyland, born 1937), known as Bernie Hyland, is an Australian botanist. He has contributed significantly to the understanding of Australian plants, in particular numerous species of his home and workplace ...

described a new variety of the species, ''C. a.'' var. ''montana'', which was published in ''

Flora of Australia The flora of Australia comprises a vast assemblage of plant species estimated to over 21,000 vascular and 14,000 non-vascular plants, 250,000 species of fungi and over 3,000 lichens. The flora has strong affinities with the flora of Gondwana, ...

'' volume 16. His description was based on a specimen he collected himself in 1972. The species has been placed in the subfamily

Grevilleoideae The Grevilleoideae are a subfamily of the plant family Proteaceae. Mainly restricted to the Southern Hemisphere, it contains around 46 genus, genera and about 950 species. Genera include ''Banksia'', ''Grevillea'', and ''Macadamia''. Descriptio ...

because its

cotyledon A cotyledon ( ; ; "a cavity, small cup, any cup-shaped hollow", gen. (), ) is a "seed leaf" – a significant part of the embryo within the seed of a plant – and is formally defined as "the embryonic leaf in seed-bearing plants, one or mor ...

s have auricles, which is unique to the subfamily.

Etymology

The genus name ''Carnarvonia'' was given by Mueller to honour Henry Howard Molyneux Herbert, the Fourth Earl of Carnarvon. The

species epithet Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In Taxonomy (biology), taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany) ...

''araliifolia'' is a combination of the genus ''

Aralia ''Aralia'' , or spikenard, is a genus of the family Araliaceae, consisting of 68 accepted species of deciduous or evergreen trees, shrubs, and rhizomatous herbaceous perennials. The genus is native to Asia and the Americas, with most species oc ...

'' and the Latin word ''folium'', 'leaf', and refers to the similarity of the leaves to those of some ''Aralia'' species.

Distribution and habitat

The variety ''C. a. araliifolia'' is native to the coastal rainforests of northeastern Queensland, from

Cooktown Cooktown is a coastal town and locality in the Shire of Cook, Queensland, Australia. Cooktown is at the mouth of the Endeavour River, on Cape York Peninsula in Far North Queensland where James Cook beached his ship, the '' Endeavour'', for ...

south to Ingham, and from near sea level up to about . The other variety, ''C. a. monticola'', has a smaller range from the

Windsor Tablelands The Windsor Tablelands are a series of plateaus located in Far North Queensland, Australia. The Windsor Tableland and surrounding rainforest area are contained as part of the Wet Tropics of Queensland, sitting between the Daintree Rainforest a ...

in the north to the southern edge of the

Atherton Tableland The Atherton Tableland is a fertile plateau, which is part of the Great Dividing Range in Queensland, Australia. It has very deep, rich basaltic soils and the main industry is agriculture. The principal river flowing across the plateau is the B ...

, and in altitudes from . Both varieties grow in well developed rainforest

Ecology

The fruits are eaten by

sulphur-crested cockatoo The sulphur-crested cockatoo (''Cacatua galerita'') is a relatively large white cockatoo found in wooded habitats in Australia, New Guinea, and some of the islands of Indonesia. They can be locally very numerous, leading to them sometimes being ...

s (''Cacatua galerita'') and

cassowaries Cassowaries (; Biak language, Biak: ''man suar'' ; ; Papuan_languages, Papuan: ''kasu weri'' ) are flightless birds of the genus ''Casuarius'', in the order Casuariiformes. They are classified as ratites, flightless birds without a keel (bird a ...

(''Casuarius casuarius'').

Conservation

This species is listed by both the Queensland Department of Environment and Science and the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

least concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

Uses

The timber of ''C. araliifolia'' has a rich red colour and is hard wearing. It has been used in house construction, especially for polished floors.

Gallery

File:Carnarvonia araliifolia 174625174.jpg, Fruit File:Carnarvonia-araliifolia-SF22332-03.jpg, Trunk File:Carnarvonia-araliifolia-SF22332-06.jpg, Small rounded buttresses File:Carnarvonia-araliifolia-SF22332-01.jpg, Foliage File:Carnarvonia-araliifolia-SF22335-01.jpg, Foliage File:Carnarvonia-araliifolia-SF22335-04.jpg, Compound leaf, upper side, with 13 leaflets File:Carnarvonia-araliifolia-SF22335-03.jpg, Under side of leaf

References

External links

View a map
of historical sightings of this species at the

Australasian Virtual Herbarium The ''Australasian Virtual Herbarium'' (AVH) is an online resource that allows access to plant specimen data held by various Australian and New Zealand herbaria. It is part of the Atlas of Living Australia (ALA), and was formed by the amalgama ...

View observations
of this species on

iNaturalist iNaturalist is an American 501(c)(3) nonprofit social network of naturalists, citizen scientists, and biologists built on the concept of mapping and sharing observations of biodiversity across the globe. iNaturalist may be accessed via its web ...

View images
of this species on Flickriver {{Taxonbar, from1=Q5752777, from2=Q9697512 Grevilleoideae Proteales of Australia Trees of Australia Taxa named by Ferdinand von Mueller Plants described in 1867 Endemic flora of Queensland Wet Tropics of Queensland