Juniperus lutchuensis | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Gymnospermae |
Division: | Pinophyta |
Class: | Pinopsida |
Order: | Cupressales |
Family: | Cupressaceae |
Genus: | Juniperus |
Section: | Juniperus sect. Juniperus |
Species: | J. lutchuensis
|
Binomial name | |
Juniperus lutchuensis | |
Synonyms | |
Juniperus lutchuensis or Ryūkyū juniper (オキナワハイネズ, Okinawa-hainezu) ( syn. Juniperus taxifolia var. lutchuensis (Koidz.) Satake) is a species of juniper native to the Ryūkyū Islands, Izu Islands, Izu Peninsula, and Bōsō Peninsula, Japan. [3] [4] [5]
Juniperus lutchuensis was first described by Gen'ichi Koidzumi in 1918, with Okinawa Island the type locality. [1]: 138 In 1962, Satake Yoshisuke treated it as a variety of Juniperus taxifolia. [2] Some authors [6] treat it as a synonym of Juniperus taxifolia from the Bonin Islands, while others treat it as a variety of it, Juniperus taxifolia var. lutchuensis. It is probably best considered a separate species as it has a distinct DNA profile clearly different from J. taxifolia. [3]
Juniperus lutchuensis is an evergreen coniferous shrub growing to a height of 1–3 metres (3+1⁄2–10 ft). Its many branches may spread some 2–4 metres (6+1⁄2–13 ft). [5] The leaves are needle-like, in whorls of three, light green, 7–14 millimetres (1⁄4–1⁄2 in) long and 1–1.5 mm broad, with a double white stomatal band (split by a green midrib) on the inner surface. It is dioecious, with separate male and female plants.
The seed cones are berry-like, green ripening in 18 months to purple-brown; they are spherical, 8–9 mm diameter, and have three or six fused scales in one or two whorls of three; the three larger scales each bear a single seed. The seeds are dispersed when birds eat the cones, digesting the fleshy scales and passing the hard seeds in their droppings. The pollen cones are yellow, 5 mm long. [3]
Endemic to Japan, it may be found growing in coastal areas, on cliffs and in sunny spots, on the Izu Peninsula and Bōsō Peninsula of Honshū, the Izu Islands, Tanegashima ( Ōsumi Islands), Tokara Islands, Amami Ōshima and Tokunoshima ( Amami Islands), and, within Okinawa Prefecture, on Okinawa Island and Yagaji Island , Iheya Island, Izena Island, and Aka Island, Tokashiki Island, and Zamami Island ( Kerama Islands). [5]
Much of its habitat has been lost due to coastal development and revetments, and it has also often been taken from the wild for use in gardens and bonsai. [5] Its conservation status is uncertain, but it is rare and may become threatened. [3] In the 2018 Okinawa Red Data Book, Juniperus taxifolia var. lutchuensis is assessed as Endangered. [5]