Ficus obliqua

Commonly known as the small-leaved fig, Ficus obliqua was described by German naturalist Georg Forster in 1786 based on type material collected in Vanuatu. Dutch botanist Friedrich Miquel described Urostigma eugenioides from Albany Island in Queensland in 1861, which was reclassified by Victorian Government Botanist Ferdinand von Mueller as Ficus eugenioides in 1867, and it was known as this for many years. However, as Forster's name is older, it takes precedence. The specific epithet is the Latin adjective obliquus, meaning "oblique", although the attribute it refers to is unclear. Frederick Manson Bailey described Ficus tryonii in 1906, from a collection at altitude on Middle Percy Island in the Whitsunday Islands off central Queensland, which is now regarded as F. obliqua. Joseph Banks and Daniel Solander collected and named Ficus virginea from Booby Island in 1770, which was synonymised with F. obliqua by William Philip Hiern in 1901. The species is currently regarded as monotypic. Three varieties of Ficus obliqua were recognised until 2001—F. obliqua var. petiolaris, F. obliqua var. obliqua, and F. obliqua var. puberula from Western Australia. A revision of the group led to the conclusion that F. obliqua var. petiolaris belonged in the species F. rubiginosa. F. obliqua var. puberula was found to be more distantly related to obliqua than rubiginosa and hence has been reclassified as a separate species, Ficus brachypoda. With over 750 species, Ficus is one of the largest angiosperm genera. Based on morphology, English botanist E. J. H. Corner divided the genus into four subgenera, which was later expanded to six. In this classification, Ficus obliqua was placed in subseries Malvanthereae, series Malvanthereae, section Malvanthera of the subgenus Urostigma. In his reclassification of the Australian Malvanthera, Australian botanist Dale J. Dixon altered the delimitations of the series within the section, but left this species in the series Malvanthereae. In a study published in 2008, Nina Rønsted and colleagues analysed the DNA sequences from the nuclear ribosomal internal and external transcribed spacers (ITS and ETS), and the glyceraldehyde-3-phosphate dehydrogenase (G3pdh) region, in the first molecular analysis of the section Malvanthera. They found F. obliqua to be most closely related to three species of the arid Northern Territory (F. platypoda, F. subpuberula and F. lilliputiana) and classified it in a new series Obliquae in the subsection Platypodeae. The species had remained a transitional rainforest species while its relatives radiated into dryer regions. == Description ==

, Barrington Tops, Australia. Ficus obliqua is a tree, which may reach in height with a similar crown width. They are alternately arranged on the stems. As is the case with all figs, the fruit is an inverted inflorescence known as a syconium, with tiny flowers arising from the inner surface. Historically, there has been some confusion between Ficus obliqua and the related F. rubiginosa. Some forms of F. rubiginosa have both leaves and petioles glabrous while others have both covered in fine fur. == Distribution and habitat ==

Ficus obliqua occurs from Mount Dromedary (36° S) in southern New South Wales northwards along the coast and Great Dividing Range to the tip of Cape York Peninsula in north Queensland. Outside Australia it occurs on New Guinea and offshore islands, where it is found in New Caledonia, Fiji, Tonga, Samoa and Vanuatu. It had been thought to occur in Western Australia, but these collections have been now referred to Ficus brachypoda. Preferring soils with high nutrient and water content, it occurs on sandstone or latite soils in the Sydney region. The habitat is warm temperate to moist subtropical rainforest. Large specimens can rise above the canopy as emergent trees. == Ecology ==

The double-eyed fig parrot (Cyclopsitta diophthalma) eats the fruit of Ficus obliqua, steadily depositing fruity detritus on the ground. The rainbow lorikeet (Trichoglossus moluccanus) is another parrot that consumes the fruit and disperses the seeds; and crimson-crowned fruit dove (P. porphyraceus), and has been recommended for amenity planting in Tonga for these birds. The spectacled flying fox (Pteropus conspicillatus) and grey-headed flying fox (Pteropus poliocephalus) also eat the fruit. the no-brand crow (Euploea alcathoe), and the Geometer moth species Scopula epigypsa. The thrips species Gynaikothrips australis feeds on the underside of new leaves of F. obliqua, as well as F. rubiginosa and F. macrophylla. As plant cells die, nearby cells are induced into forming meristem tissue. A gall results and the leaves become distorted and curl over. The thrips remain in the galls at night and wander about in the daytime before returning in the evening, possibly to different galls about the tree. The thrips begin feeding when the tree has flushes of new growth, and the life cycle is around six weeks. At other times, thrips reside on old leaves without feeding or pupate sheltered in the bark. Reproduction and life span and has increasing numbers of roots reaching the ground, Watagan Mountains Figs have an obligate mutualism with fig wasps (Agaonidae); figs are only pollinated by fig wasps, and fig wasps can only reproduce in fig flowers. Generally, each fig species depends on a single species of wasp for pollination. The wasps are similarly dependent on their fig species to reproduce. The assumption that fig species are usually pollinated by just one species of fig wasp has been challenged by the discovery of cryptic species complexes among what was previously thought to be single species of fig wasps. Ficus obliqua is pollinated by two species of fig wasp—Pleistodontes greenwoodi and P. xanthocephalus. Female and male flowers in each syconium mature at different times. Female wasps enter the syconium and lay eggs in the female flowers as they mature. These eggs later hatch and the progeny mate. The females of the new generation collect pollen from the male flowers, which have matured by this point, and leave to visit other syconia and repeat the process. A field study in Brisbane found that F. obliqua trees often bore both male and female syconia at the same time—this could be beneficial for reproduction in isolated populations, such as those on islands. The same study found a slightly reduced number of male phase syconia in winter, thought due to increased mortality of the wasp pollinator in cooler months. The animals that eat the figs disperse the seeds, which then germinate and grow on other plants (epiphytes) or on rocks (lithophytes). As the new plants develop, they send roots to the forest floor. Figs growing on other plants grow larger and larger until they strangle their hosts. Ficus obliqua is long-lived, and trees are thought to live in excess of 500 years. == Uses ==

Ficus obliqua is an elegant shade tree for parks or fields, and is adaptable to differing soils. and is a local landmark. Like other fig species that grow into large trees, Ficus obliqua is not suitable for any but the largest gardens as its aggressive root system invades drains and garden beds. Fig trees also drop large quantities of fruit and leaves, leaving a mess underfoot. F. obliqua is well-suited for use in the medium; its small leaves and trunk's propensity to thicken give it attributes optimal for a tree in height. It is seen in bonsai nurseries mainly in the Brisbane area, where it is a locally common species, and is very highly regarded by at least one proponent, Bradley Barlow. Barlow entered a specimen from Brisbane to the Bonsai Clubs International competition in 2006, winning a prize. It is also suited for use as an indoor plant in low-, medium- or brightly lit indoor spaces. The timber is too soft for use in woodworking. Its white sap has been used for painful or swollen joints and limbs or boils, or diluted with water and drunk to improve breast milk. Liquid extracted from the root bark has been used for headaches or, when diluted, to improve health after childbirth, and the leaves are applied to venereal lesions. The species has been traditionally used for boils in Samoa and Tonga. == References ==