Cycas brunnea | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Gymnospermae |
Division: | Cycadophyta |
Class: | Cycadopsida |
Order: | Cycadales |
Family: | Cycadaceae |
Genus: | Cycas |
Species: | C. brunnea |
Binomial name | |
Cycas brunnea K.D.Hill | |
Cycas brunnea is a species of cycad in the genus Cycas , native to northern Australia in northwest Queensland and northeast Northern Territory in a small area straddling the border of the two regions. It occurs on exposed sites in savanna and creek valleys on sandstone and limestone derived soils, with moderate seasonal rainfall.
The stems grow to 2–5 m tall, with numerous leaves in the crown. The leaves are 1.2-1.7 m long, glabrous with age, pinnate, with 160-240 leaflets, the leaflets 17–27 cm long and 6–7.5 mm wide. The petioles are covered in brown tomentum and armed with sharp spines.
The female cones are open, with sporophylls 28–32 cm long. Orange tomentose covering cone, with serrations along margins of the lamina. The sarcotesta is orange and glaucous, the sclerotesta ovoid and flattened. The male cones are solitary and long ovoid, 21 cm long and 13 cm diameter, brown tomentose, and with an upturned apical spine.
It was first described in 1992, and is similar in appearance to Cycas angulata . It is considered near-threatened due to its restricted range, though it occurs in some protected areas including Boodjamulla National Park. It is named after the Greek word brunneus (brown), as the emergent leaves are brown tomentose.
Cycas angulata is a species of cycad in the genus Cycas, native to Australia in northeast Northern Territory and northwest Queensland.
Cycas apoa is a species of cycad in the genus Cycas, native to northern New Guinea and Halmahera Island. It occurs in the Sepik River basin, in wet lowland forest in modestly seasonally flooded areas.
Cycas arenicola is a species of cycad in the genus Cycas, native to Australia, in the far north of Northern Territory in the basin of the upper East Alligator River in Arnhem Land. It grows in Eucalyptus woodlands on highly siliceous soils. They thrive in open situations.
Cycas armstrongii is a species of cycad in the genus Cycas, endemic to Northern Territory of Australia. It is found from the Finniss River in the west to the Arnhem Highway in the east, north of Pine Creek. It also occurs on the Tiwi Islands and the Cobourg Peninsula
Cycas arnhemica is a species of cycad in the genus Cycas, native to Australia, in the northwest of Northern Territory in Arnhem Land, after which it is named.
Cycas badensis is a species of cycad in the genus Cycas, native to Australia, in the extreme north of Queensland, where it is endemic on Badu Island in the Torres Strait Islands.
Cycas balansae is a species of cycad in the genus Cycas, native to southwestern China and adjacent northern Vietnam, where it occurs in dense mountain rainforests.
Cycas basaltica is a species of cycad in the genus Cycas, native to Australia, in the far north of Western Australia in the Kimberley region.
Cycas beddomei is a species of cycad in the genus Cycas, native to India, where it is confined to a small area of Andhra Pradesh state in the Tirumala Hills in scrubland and brush covered hills.
Cycas bifida is a species of cycad plant in the genus Cycas, native to southern China, and northern Vietnam.
Cycas bougainvilleana is a species of cycad in the genus Cycas, native to the islands northeast of Papua New Guinea, on New Britain, the Bismarck Archipelago and the Solomon Islands, where it occurs on or near the coast in calcareous coral sand dunes and in adjacent forests.
Cycas brachycantha is a species of cycad in the genus Cycas, native to northern Vietnam where it is endemic to Bắc Kạn Province. It grows in often soil-free cracks and crevices of limestone crests and ridges under the canopy of evergreen forests. It is found in Ba Bể National Park.
Cycas cairnsiana is a species of cycad in the genus Cycas, native to northern Australia in northern Queensland on the Newcastle Range.
Cycas calcicola is a species of cycad in the genus Cycas, native to northern Australia in the northwest of Northern Territory.
Cycas campestris is a species of cycad in the genus Cycas, native to southeastern Papua New Guinea in the lowland region near Port Moresby. It grows in open, grassy locations, often in areas with frequent grass fires.
Cycas canalis is a species of cycad in the genus Cycas, native to northern Australia in the northwest of Northern Territory, where it occurs in two areas, on the coast at Channel Point, and inland in the Daly River area near Dorisvale.
Cycas chamaoensis is named after the only known habitat of this species, on and near Khao Chamao mountain in Khao Chamao District, Thailand. Stems are arborescent, either erect or decumbent. Leaves numerous, exceeding 60 per crown, 1.2-2.5 meters in length, ending in terminal spine. Petiole 30–60 cm, glabrous and partially spiny. Leaflets in 85-155 pairs, and lanceolate, glabrous and angled forward at 60-70 degrees.
Cycas micronesica is a species of cycad found on the island of Yap in Micronesia, the Marianas islands of Guam and Rota, and The Republic of Palau. It is commonly known as federico nut or fadang in Chamorro. The species, previously lumped with Cycas rumphii and Cycas circinalis, was described in 1994 by Ken Hill. Paleoecological studies have determined that C. micronesica has been present on the island of Guam for about 9,000 years. It is linked with Lytico-Bodig disease, a condition similar to amyotrophic lateral sclerosis (ALS), due to the neurotoxin BMAA found in its seeds, which were a traditional food source on Guam until the 1960s. The neurotoxin is present due to its symbiosis with cyanobacteria.
Cycas thouarsii, the Madagascar cycad, is an evergreen arborescent cycad in the genus Cycas. It is named after a French botanist Louis-Marie Aubert du Petit-Thouars (1758—1831).
Cycas inermis is a vascular plant belonging to the family Cycadaceae, endemic to central and southern Vietnam. Its name in Vietnamese is Thiên tuế or Tuế lá quyết.