''Casuarina pauper'', commonly known as black oak, belah or kariku, is a species of flowering plant in the family

Casuarinaceae The Casuarinaceae are a family of dicotyledonous flowering plants placed in the order Fagales, consisting of four genera and 91 species of trees and shrubs native to eastern Africa, Australia, Southeast Asia, Malesia, Papuasia, and the Pacific ...

and 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 southern continental Australia. It is a

dioecious Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

tree with fissured or scaly bark, waxy branchlets, the leaves reduced to scales in

whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagram ...

of 9 to 13, the fruit long containing winged seeds (

samara Samara, formerly known as Kuybyshev (1935–1991), is the largest city and administrative centre of Samara Oblast in Russia. The city is located at the confluence of the Volga and the Samara (Volga), Samara rivers, with a population of over 1.14 ...

s) long.

Description

''Casuarina pauper'' is a

tree similar to '' C. cristata'', that typically grows to a height of , has a DBH of up to , and sometimes produces root suckers. The branchlets are more or less erect or spreading, up to long, the leaves reduced to scale-like teeth long, arranged in whorls of 9 to 13 around the branchlets. The sections of branchlet between the leaf whorls (the "articles") are waxy, long and wide. The flowers on male trees are arranged in spikes long, the

anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

long. The female cones are covered with rusty hairs, on a peduncle long. The mature cones are usually long and in diameter, the samaras long. This species is a poorer, stunted form of '' C. cristata'', and the two species often intergrade where their ranges overlap.

Taxonomy

''Casuarina pauper'' was first formally described in 1989 by Lawrie Johnson in the ''

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, ...

'' from a

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 ...

's unpublished description of a plant he collected in the

Flinders Ranges The Flinders Ranges are the largest mountain ranges in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna. The Adnyamathanha people are the Aboriginal group who have inhab ...

in 1851. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

(''pauper'') means "scanty" or "poor", referring to the habit of the species compared to ''C. cristata''. Johnson had previously described ''Casuarina cristata'' subsp. ''pauper'' ( Miq.) L.A.S.Johnson in the journal ''

Nuytsia ''Nuytsia floribunda'' is a hemiparasitic tree found in Western Australia. The species is known locally as moodjar and, more recently, the Christmas tree or Western Australian Christmas tree. The display of intensely bright flowers during the ...

'', based Miquel's ''C. pauper'', but the name was not valid, because Miquel explicitly did not accept von Mueller's description of ''Casuarina pauper'', considering it the same species as ''C. cristata''.

Distribution and habitat

Black oak grows in red-brown soils on open woodland, sometimes with '' Callitris gracilis'', and is widespread across southern Australia, including in the far south-west of Queensland, western New South Wales, north-western Victoria, South Australia, and inland Western Australia. This species is generally found growing in groves ranging in area from less than at altitudes from , and where the temperature ranges between .

Ecology

''Casuarina pauper'' produces abundant viable seed, with regeneration success likely to be inhibited during periods of insufficient soil moisture. When present at low densities, plants tends to reproduce sexually, while established groves extend mostly from the fringes through root suckers, increasing the local area occupied by individual plants.

References

{{Taxonbar, from=Q3538354

pauper Pauperism (; ) is the condition of being a "pauper", i.e. receiving relief administered under the Irish and English Poor Laws. From this, pauperism can also be more generally the state of being supported at public expense, within or outside of ...

Fagales of Australia Flora of New South Wales Flora of Queensland Flora of South Australia Flora of Victoria (state) Flora of Western Australia Dioecious plants Trees of Mediterranean climate Plants described in 1989 Taxa named by Lawrence Alexander Sidney Johnson