''Richea dracophylla'', commonly known as dragon heath or pineapple candleheath, is an

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 ...

shrub of

Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

. It is widespread across the south-eastern regions of Tasmania, particularly in montane and subalpine environments. The species is names for its striking, spirally arranged leaves which resemble the scales of a dragon, and its dense candle-like floral spikes.

Taxonomy and classification

''Richea dracophylla'' is a species of woody shrub in the family

Ericaceae The Ericaceae () are a Family (biology), family of flowering plants, commonly known as the heath or heather family, found most commonly in acidic and infertile growing conditions. The family is large, with about 4,250 known species spread acros ...

, which includes other members of the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Richea'' endemic to Tasmania. It shares morphological similarities with other species in the genus, particularly ''

Richea pandanifolia ''Richea pandanifolia'', the pandani or giant grass tree, is a distinctive endemic Tasmanian angiosperm. It is dicot of the family Ericaceae and is found in central, western and south west Tasmania. Description ''Richea pandanifolia'' can be ...

'', but differs in leaf structure and floral arrangement.

Description

''Richea dracophylla'' is an erect, woody shrub that typically reaches heights of 1.5 to 5 meters. The plant is characterized by its sparse branching and clusters of leaves towards the ends of the branches. The leaves are spirally arranged, tapering to a sharp point, and measure between 15 and 30 centimetres in length. They possess sheathing basses that wrap around the steam, a common feature in the ''Richea'' genus. 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 ...

s consists of dense terminal clusters of over 300 small white slower, approximately 15–30 cm long. The flowers are enclosed in a fused calyptra, which must be removes by external agents before pollination can occur. Flowering occurs over an extended period, typically from June to April, providing an important nectar source throughout the year.

Habitat and distribution

''Richea dracophylla'' is endemic to Tasmania and occurs in a variety of habitats, including rainforest, wet sclerophyll forest, montane regions, and subalpine areas. It is particularly prevalent in the south-eastern part of the state, with notable population in Wellington Park, Tasman National Parks, as well as on Bruny and Maria Islands. It grows in well-drained, acidic soils derived from

dolerite Diabase (), also called dolerite () or microgabbro, is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine-grain ...

and

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

, in high rainfall areas with no prolonged drought periods. ''Richea dracophylla'' is a common component of cool temperate rainforest vegetation, particularly when found in association with species such as ''

Nothofagus cunninghamii ''Nothofagus cunninghamii'', commonly known as myrtle beech or Tasmanian myrtle, is the dominant species of cool temperate rainforests in Tasmania and Southern Victoria. It has low fire resistance and grows best in partial shade conditions. It ...

'' (myrtle beech) and ''

Atherosperma moschatum ''Atherosperma moschatum'', commonly known as black sassafras, Australian sassafras, southern sassafras, native sassafras or Tasmanian sassafras, is a flowering plant in the family Atherospermataceae and the only species in the genus ''Atherospe ...

'' (southern sassafras). In rainforests with nutrient-poor soils, ''Richea dracophylla'' can dominate, whereas in richer soils, ''Nothofagus cunninghamii'' is often the dominant species. The largest specimens of ''Richea dracophylla'' occur in wet sclerophyll forests beneath a canopy of ''

Eucalyptus ''Eucalyptus'' () is a genus of more than 700 species of flowering plants in the family Myrtaceae. Most species of ''Eucalyptus'' are trees, often Mallee (habit), mallees, and a few are shrubs. Along with several other genera in the tribe Eucalyp ...

'' species, where they can reach their maximum height. At higher elevations, ''Richea dracophylla'' may be reduced to a stunted shrub form, particularly in subalpine areas exposed to harsh environmental conditions.

Ecological importance

''Richea dracophylla'' plays a vital role in Tasmania's montane and subalpine

ecosystem An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...

s, contributing to floral diversity and providing structural habitat for

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s and small

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

s. The species exhibits a complex pollination strategy, relying on multiple pollinators, including nectar-feeding birds, flying insects, and nocturnal ants. The long flowering season and diverse pollinator interactions enhance its reproductive success and resilience to environmental changes. Notably, the nocturnal ant ''Notoncus hickmani'' has been observed visiting flowers at night during winter, making it one of the rare examples of nocturnal ant pollination. These ants collect nectar from exposed flowers and inadvertently transfer pollen, facilitating

geitonogamy Geitonogamy (from Greek ''geiton'' (γείτων) = neighbor + ''gamein'' (γαμεῖν) = to marry) is a type of self-pollination. Geitonogamous pollination is sometimes distinguished from the fertilizations that can result from it, geitonogamy. ...

(pollination between adjacent flowers on the same plant). However, birds such as the

New Holland honeyeater The New Holland honeyeater (''Phylidonyris novaehollandiae'') is a honeyeater species found throughout southern Australia. It was among the first birds to be scientifically described in Australia, and was initially named ''Certhia novaehollandi ...

(P''hylidonyris novaehollandiae'') and

yellow wattlebird The yellow wattlebird (''Anthochaera paradoxa'') is a species of bird in the honeyeater family Meliphagidae. Other names include the long wattlebird or Tasmanian wattlebird. Taxonomy French zoologist François Marie Daudin described the yellow ...

(''Anthochaera paradoxa'') play a crucial role in removing the calyptra, enabling access for other pollinators.

Threats and conservation

Although ''Richea dracophylla'' is not currently listed as a threatened species, several factors pose potential risks to its long-term survival. Habitat destruction due to land clearing, logging, and urban expansion threatens populations in lowland areas. Additionally, climate change is expected to impact its range, as rising temperatures and altered precipitation patterns could reduce the availability of suitable habitat.

References

{{Taxonbar, from=Q7330383 dracophylla Ericales of Australia Endemic flora of Tasmania Plants described in 1810