''Bryobium retusum'', commonly known as the Christmas Island urchin orchid, is an

epiphytic An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

clump-forming

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

that has oval, fleshy green pseudobulbs, each with two leaves and between seven and twelve short-lived,

self-pollinating Self-pollination is a form of pollination in which pollen from the same plant arrives at the stigma of a flower (in flowering plants) or at the ovule (in gymnosperms). There are two types of self-pollination: in autogamy, pollen is transferred to ...

, pale green, hairy flowers. This orchid is found between

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...

and

New Caledonia ) , anthem = "" , image_map = New Caledonia on the globe (small islands magnified) (Polynesia centered).svg , map_alt = Location of New Caledonia , map_caption = Location of New Caledonia , mapsize = 290px , subdivision_type = Sovereign st ...

Description

''Bryobium retusum'' is an epiphytic

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

that forms small dense clumps with crowded, cylindrical pseudobulbs long and wide. Each pseudobulb has two linear to lance-shaped leaves long and wide. Between seven and twelve pale green flowers about long and wide are arranged on a flowering stem long. The flowers are self-pollinating, short-lived and hairy on the outside. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

and

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s are about long and wide, the petals slightly narrower than the sepals. The labellum is about long and wide with a small callus. Flowering occurs from September to November.

Taxonomy and naming

The Christmas Island urchin orchid was first formally described in 1825 by

Carl Ludwig Blume Charles Ludwig de Blume or Karl Ludwig von Blume (9 June 1796, Braunschweig – 3 February 1862, Leiden) was a German-Dutch botanist. He was born at Braunschweig in Germany, but studied at Leiden University and spent his professional life wor ...

who gave it the name ''Dendrolirium retusum'' and published the description in ''Bijdragen tot de flora van Nederlandsch Indië''. In 2005 Yan Peng Ng and Phillip Cribb changed the name to ''Bryobium retusum''. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

(''retusum'') is a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word meaning "blunted", "rounded" or "notched at the apex".

Distribution and habitat

''Bryobium retusum'' grows near the top of rainforest trees. It is found in

Borneo Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...

, Java, the

Lesser Sunda Islands The Lesser Sunda Islands or nowadays known as Nusa Tenggara Islands ( id, Kepulauan Nusa Tenggara, formerly ) are an archipelago in Maritime Southeast Asia, north of Australia. Together with the Greater Sunda Islands to the west they make up t ...

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

, the

Solomon Islands Solomon Islands is an island country consisting of six major islands and over 900 smaller islands in Oceania, to the east of Papua New Guinea and north-west of Vanuatu. It has a land area of , and a population of approx. 700,000. Its capita ...

, New Caledonia and the

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

n territory of Christmas Island.

References

External links

* {{Taxonbar, from=Q15495689 retusum Orchids of Australia Orchids of Indonesia Orchids of New Caledonia Orchids of New Guinea Plants described in 1825