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''Diselma archeri'' (Dwarf Pine) or (Cheshunt pine) is a species of plant of the family Cupressaceae and the sole species in the genus ''Diselma''. It is endemic to the alpine regions of Tasmania's southwest and Central Highlands, on the western coast ranges and Lake St. Clair. It is a monotypic genus restricted to high altitude rainforest and moist alpine heathland. Its distribution mirrors very closely that of other endemic Tasmanian conifers ''Microcachrys tetragona'' and ''Phaerosphaera hookeriana'' but differ in growth pattern. == Appearance and Ecology == ''D. archeri'' is a compact, prostrate shrub which commonly reaches 1–4 m in height but has been recorded to reach greater heights in subalpine rainforest zones. The foliage has a grey-green appearance with branchlets curving downward at their tips. Branches are short, ridged and very numerous. Branchlet foliage appears square in cross-section and scale-like leaves (2–3 mm) are overlapping and arranged in opposite decussate pairs which are pressed close to the stem.〔Kirkpatrick, J. 1997. Alpine Tasmania. An illustrated guide to the flora and vegetation. Oxford University Press" Melbourne. P. 18-19.〕 The square leaf arrangement is similar to that of ''Microcachrys tetragona'' (Podocarpaceae) (Creeping Pine) and the two species can easily be confused. However, ''M. tetragona'' lives up to its name and grows low to the ground, spreading out with only occasional erect branches. Another species which can be confused with ''Diselma'' is ''Phaerosphaera hookeriana'' (previously known as ''Microstrobos niphophilus'' ) which is also part of the Podocarpaceae family. Both these species have a similar growth habit and distribution, however, the opposite pairs of leaves on ''D. archeri'' again make it distinguishable from the other species.〔http://www.utas.edu.au/dicotkey/dicotkey/CONIFERS/sPhaerosphaera.htm〕 Bark is rough and scaly and often weathered revealing a reddish-brown inner bark. Being a gymnosperm no flowers are produced, instead seed development occurs on the surface of the scale-like leaves which are modified to form cones (see image).〔Raven, P.H., Evert, R.F., Eichorn, S.E. 2003. Biology of Plants. 6th Edition. W.H Freeman and Company〕 "D. archeri" is a dioecious shrub, where male and female cones are located on separate individuals. Both types of cones are very small (3–4 mm) and occur at the branch tips. The female cone is composed of two pairs of opposite cone scales and only the upper pair of scales are fertile. Once germinated up to four small winged seeds are produced which are wind dispersed.〔http://www.conifers.org/cu/Diselma.php〕 ''D. archeri'' seedlings are uncommon as the species often re-sprouts from roots and trunks buried in peat soils. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Diselma」の詳細全文を読む スポンサード リンク
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