''Eucalyptus arcana'', commonly known as the Mallee manna gum or Carpenter Rocks gum
is a
mallee that is
endemic to
South Australia. It has rough bark from the base of the trunk to the thinnest branches, lance-shaped, sometimes curved leaves, flower buds in groups of seven, white flowers and hemispherical fruit. It is only known from a single population near
Carpenter Rocks.
Description
''Eucalyptus arcana'' is a low, straggly tree, sometimes with several stems, that typically grows to high. It has rough, fibrous, grey to grey-brown bark from the base of the trunk to the larger branches, and smooth, grey to cream bark on the thinnest branches. Young plants and
coppice regrowth have four-sided stems and glossy elliptic to egg-shaped leaves long and wide with wavy edges. Adult leaves are lance-shaped, the same glossy green on both sides, with a blade that is long and wide on a
petiole long. The flowers buds are arranged in groups of seven on a
peduncle Peduncle may refer to:
*Peduncle (botany), a stalk supporting an inflorescence, which is the part of the shoot of seed plants where flowers are formed
*Peduncle (anatomy), a stem, through which a mass of tissue is attached to a body
**Peduncle (art ...
long, the individual flowers on a
pedicel up to long. Mature buds are oval to spindle-shaped, long and wide with an
operculum that is shaped like a blunt cone, about equal in length to the
floral cup
In angiosperms, a hypanthium or floral cup is a structure where basal portions of the calyx, the corolla, and the stamens form a cup-shaped tube. It is sometimes called a floral tube, a term that is also used for corolla tube and calyx tube. It ...
. Flowering occurs in February and the flowers are white. The fruit are hemispherical to cone-shaped, long and wide containing dark brown to black ovoid seeds.
Taxonomy and naming
Mallee manna gum was first formally described in 1998 by
Dean Nicolle
image:Dean-Nicolle-Deanei.JPG, 270px, Dean Nicolle and ''Eucalyptus deanei''
Dean Nicolle (born 1974), is an Australian botanist, arboriculture, arborist and ecologist. He is widely recognised as the leading authority on the genus ''Eucalyptus''.
...
and
Ian Brooker who gave it the name ''Eucalyptus splendens'' subsp. ''arcana'' and published the description in the ''
Journal of the Adelaide Botanic Gardens''.
In 2009
Kevin Rule
Kevin James Rule was born at Daylesford, Victoria on 9 November 1941. He was a secondary school teacher and had a particular interest in the taxonomy of Australian eucalyptus. He discovered several new species in Victoria. He is an honorary asso ...
raised it to species status as ''E. arcana''.
The
specific epithet
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
(''arcana'') is a
Latin word meaning "secret" or "mysterious", referring to the species being hidden in dense scrub.
Distribution and habitat
''Eucalyptus arcana'' has a limited range and occurs on low rises in shallow, impoverished, red clay-loam soils over limestone around the coastal town of Carpenter Rocks in south-east South Australia. It is found amongst dense tall shrubland, associated with species including ''
Eucalyptus obliqua'' and ''
Eucalyptus ovata''. The populations that Nicolle and Brooker described as ''E. splendens'' subsp. ''arcana'' occurring near Moonlight Head in south-west
Victoria have been assessed as a form of ''
E. aromaphloia''.
See also
* List of ''Eucalyptus'' species
* Carpenter Rocks Conservation Park
References
{{Taxonbar, from=Q28813538
Trees of Australia
arcana
Arcana may refer to: Music
* Arcana (American band), an American jazz band
* Arcana (Swedish band), a Swedish dark wave band
* Arcana (record label), a French classical record label
* Arcana (album), ''Arcana'' (album), a 2001 album by Edenbridge ...
Myrtales of Australia
Flora of South Australia
Plants described in 2009