Microcachrys tetragona, known as creeping pine or creeping strawberry pine, is a species of dioecious conifer belonging to the podocarp family (Podocarpaceae).[Christopher N. Page. 1990. "Podocarpaceae" pages 332-346. In: Klaus Kubitzki (general editor); Karl U. Kramer and Peter S. Green (volume editors) The Families and Genera of Vascular Plants volume I. Springer-Verlag: Berlin;Heidelberg, Germany. ] It is the sole species of the genus Microcachrys.[James E. Eckenwalder. 2009. Conifers of the World. Timber Press: Portland, OR, USA. .] The plant is endemic to western Tasmania, where it is a low shrub growing to 1 Meter tall at high altitudes. Its leaf are scale-like, arranged (unusually for the Podocarpaceae) in opposite Phyllotaxis pairs, superficially resembling those of the unrelated Diselma archeri (Cupressaceae). It shares the common name Creeping pine with Creeping pine. Females produce tiny, red, edible berries in summer.
Fossil record and paleoendemism
Microcachrys has been called one of the most spectacular cases of
paleoendemism. It is a known relictual plant, being widespread in the past but now having a very restricted distribution.
[Carpenter, Raymond J., et al. "Leaf fossils of the ancient Tasmanian relict Microcachrys (Podocarpaceae) from New Zealand." American Journal of Botany 98.7 (2011): 1164-1172] The only extant species today,
Microcachrys tetragona, produces a very distinctive pollen grain compared with other members of its family,
Podocarpaceae, and records of fossil pollen from the genus have been recorded from all over the Southern Hemisphere throughout the
Cenozoic, being found in Antarctica,
[Truswell, E. M., and M. K. Macphail. "Polar forests on the edge of extinction: what does the fossil spore and pollen evidence from East Antarctica say?." Australian Systematic Botany 22.2 (2009): 57-106.] Australia,
[Macphail, M. K., N. F. Alley, E. M. Truswell, and I. R. K. Sluiter. 1994. Early Tertiary vegetation: evidence from spores and pollen. In R. S. Hill ed., History of the Australian vegetation: Cretaceous to Recent, 189–261. Cambridge University Press, Cambridge, UK.] the now sunken islands of the Ninetyeast Ridge of the Indian Ocean,
[Kemp, E. M., and W. K. Harris. 1977. The palynology of early Tertiary sediments, Ninetyeast Ridge, Indian Ocean. Palaeontological Association of London. Special Papers in Palaeontology 19: 1–69.] New Zealand,
[Raine, J. I., D. C. Mildenhall, and E. M. Kennedy. 2008. New Zealand fossil spores and pollen: an illustrated catalogue, 3rd ed. GNS Science Miscellaneous Series No. 4. GNS Science, Lower Hutt, New Zealand. Website spore_pollen/catalog/index.htm accessed.] southern Africa
[Coetzee, J. A., and J. Muller. 1984. The phytogeographic significance of some extinct Gondwana pollen types from the Tertiary of the southwestern Cape (South Africa). Annals of the Missouri Botanical Garden 71: 1088–1099.] and South America.
[Barreda, V. 1997. Palynomorph assemblage of the Chenque Formation, Late Oligocene?—Miocene from Golfo San Jorge Basin, Patagonia, Argentina. Part 2: Gymnosperm and colpate pollen. Ameghiniana 34: 81–92.] Ocean drillings in the Kerguelen Plateau near Heard Island have revealed conifer remains with twigs very similar in appearance to those of
Microcachrys.
The genus Microcachrys clearly had a very broad, Gondwana distribution. But now, the sole surviving species, Microcachrys tetragona, is a shrub restricted to Tasmanian mountain thickets and boulder-fields.[Carpenter, Raymond J., et al. "Leaf fossils of the ancient Tasmanian relict Microcachrys (Podocarpaceae) from New Zealand." American Journal of Botany 98.7 (2011): 1164-1172] The fossil record of Microcachrys is one of many compelling lines of evidence which points to the highly dynamic and changing Southern Hemisphere vegetation through the Cenozoic since the break up of Gondwana.
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