''Polyscias racemosa'', or false 'ohe, is a species of flowering plant in the family Araliaceae. As ''Munroidendron racemosum'', the species was until recently considered to be the only species in the monotypic genus ''Munroidendron''. With the change in classification, ''Munroidendron'' is now obsolete. ''Polyscias racemosa'' is endemic to the Hawaiian island of

Kauai Kauai, () anglicized as Kauai ( ), is geologically the second-oldest of the main Hawaiian Islands (after Niʻihau). With an area of 562.3 square miles (1,456.4 km2), it is the fourth-largest of these islands and the 21st largest island ...

.David G. Frodin and Rafaël Govaerts. 2003. ''World Checklist and Bibliography of Araliaceae''. Royal Botanic Gardens, Kew. . (See ''External links'' below). It is very rare in the

wild Wild, wild, wilds or wild may refer to: Common meanings * Wild animal * Wilderness, a wild natural environment * Wildness, the quality of being wild or untamed Art, media and entertainment Film and television * ''Wild'' (2014 film), a 2014 A ...

and some of its original habitat has been replaced by sugar cane plantations.Earl Edward Sherff. 1956. "Some Recently Collected Dicotyledonous Hawaiian Island and Peruvian Plants". ''American Journal of Botany'' 43(7):475-478. It was thought for some time to be probably

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

, but was rediscovered a few years prior to 1967.Benjamin C. Stone. 1967. "A review of the endemic genera of Hawaiian plants" ''Botanical Review'' (Lancaster) 33(3):216-259. Using cladistic methods, phylogenetic

studies Study or studies may refer to: General * Education **Higher education * Clinical trial * Experiment * Observational study * Research * Study skills, abilities and approaches applied to learning Other * Study (art), a drawing or series of drawin ...

of DNA have shown that the closest relative of ''Munroidendron racemosum'' is '' Reynoldsia sandwicensis''.Gregory M. Plunkett and Porter P. Lowry II. 2010. "Paraphyly and polyphyly in ''Polyscias'' sensu lato: molecular evidence and the case for recircumscribing the "pinnate genera" of Araliaceae". ''Plant Diversity and Evolution'' (formerly ''Botanische Jahrbucher'') 128(1-2):23-54. . These two species are now known as ''Polyscias racemosa'' and '' Polyscias sandwicensis'', respectively. They are two of the 21 species now placed in ''Polyscias'' subgenus ''Tetraplasandra''.Porter P. Lowry II and Gregory M. Plunkett. 2010. "Recircumscription of ''Polyscias'' (Araliaceae) to include six related genera, with a new infrageneric classification and a synopsis of species". '' Plant Diversity and Evolution'' (formerly ''Botanische Jahrbucher'') 128(1-2):55-84. . (See ''External links'' below). ''Polyscias racemosa'' is known in cultivation in Hawaii.Clyde T. Imada, George W. Staples, and Derral R. Herbst. undated. Annotated Checklist of Cultivated Plants of Hawai‘i. (See ''External links'' below). Cultivation procedures for ''Polyscias racemosa'' have been studied.Kerin E. Lilleeng-Rosenberger. 2005. ''Growing Hawaii's Native Plants''. Mutual Publishing.

Description

''Polyscias racemosa'' is a small tree growing to tall, with a straight

trunk Trunk may refer to: Biology * Trunk (anatomy), synonym for torso * Trunk (botany), a tree's central superstructure * Trunk of corpus callosum, in neuroanatomy * Elephant trunk, the proboscis of an elephant Computing * Trunk (software), in rev ...

, spreading branches, and smooth, grey

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, ...

.Warren L. Wagner, Derral R. Herbst, and Sy H. Sohmer. ''Manual of the Flowering Plants of Hawaii'', Revised Edition, 1999. Bishop Museum Press: Hololulu Like many members of ''Polyscias'', it is sparingly branched and thick- stemmed, with large imparipinnate leaves, but not as extreme in these characteristics as is ''

Polyscias nodosa ''Polyscias'' is a genus of flowering plants in the family Araliaceae. They bear pinnately compound leaves. In 2003, a checklist and nomenclator was published for Araliaceae.David G. Frodin and Rafaël Govaerts. 2003. ''World Checklist and Bibl ...

''. Its

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are pinnate, long, with oval leaflets, each of which is over long. These trees are dry season deciduous, dropping most of their leaves during their

summer Summer is the hottest of the four temperate seasons, occurring after spring and before autumn. At or centred on the summer solstice, the earliest sunrise and latest sunset occurs, daylight hours are longest and dark hours are shortest, wit ...

blooming Bloom or blooming may refer to: Science and technology Biology * Bloom, one or more flowers on a flowering plant * Algal bloom, a rapid increase or accumulation in the population of algae in an aquatic system * Jellyfish bloom, a collective ...

season. Its small, pale yellow flowers hang in long, rope-like strands. The inflorescence is racemose in form, with up to 250 flowers.Peter S. Green (author) and Mary Grierson (illustrator). 1996. ''A Hawaiian Florilegium: Botanical Portraits from Paradise''. University of Hawaii Press: Honolulu, Hawaii. . File:Polyscias racemosa (5454956091).jpg, Flowers File:Polyscias racemosa (5455568842).jpg, Inflorescence File:Starr-090421-6250-Polyscias racemosa-leaves-Keikilani Rd Pukalani-Maui (24952473915).jpg, Leaves File:Starr 061108-9821 Munroidendron racemosum.jpg, New Leaves

Habitat and range

''Polyscias racemosa'' occurs in coastal mesic and mixed mesic forests at elevations of , where it grows on exposed cliffs and ridges. Associated plant species include papala kepau ('' Pisonia umbellifera''), āwikiwiki ('' Canavalia

galeata Galeata ( rgn, Gagliêda) is a ''comune'' (municipality) in the Province of Forlì-Cesena in the Italian region Emilia-Romagna, located about southeast of Bologna and about southwest of Forlì. Galeata borders the following municipalities: Civ ...

''), ilima ('' Sida fallax''), ōlulu ('' Brighamia insignis''), alahee ('' Psydrax odorata''), kōpiko ('' Psychotria'' spp.), olopua (''

Nestegis sandwicensis ''Nestegis sandwicensis'', commonly known as Hawai'i olive or ''olopua'', is a species of flowering tree in the olive family, Oleaceae, that is endemic to Hawaii. It is found on all major islands at elevations of in coastal mesic and mixed mes ...

''), ahakea (''

Bobea timonioides ''Ahakea'' (''Bobea timonioides'') is a species of flowering tree in the coffee family, Rubiaceae, that is endemic to Hawaii. It inhabits dry, coastal mesic and mixed mesic forests at elevations of on the islands of Hawaii and Maui. It is th ...

''), hala pepe (''

Pleomele aurea ''Dracaena aurea'', the golden hala pepe, is a species of flowering plant that is endemic to the island of Kauai in Hawaii. It inhabits coastal mesic and mixed mesic forests at elevations of . It is a small evergreen tree, usually tall, but ...

''), and ālaa ('' Pouteria sandwicensis''). It occurs naturally in only three locations on Kauai: Nounou Mountain, the cliffs of the Nā Pali Coast, and Haupu Ridge near Nāwiliwili Bay.

History

''Polyscias racemosa'' first entered the botanical literature in 1917, when it was described and named as ''Tetraplasandra racemosa'' by

Charles Noyes Forbes Charles Noyes Forbes (1883–1920) was an American botanist who primarily worked on Hawaii. Biography Forbes was born in Boylston, Massachusetts on 24 September 1883.Occasional papers of the Bernice Pauahi Bishop Museum of Polynesian Ethnolog ...

.Charles Noyes Forbes. 1917. "New Hawaiian Plants.-VI." ''Occasional Papers of the Bernice Pauahi Bishop Museum'' 6(4):51. (See ''External links'' below).

Earl Edward Sherff Earl () is a rank of the nobility in the United Kingdom. The title originates in the Old English word ''eorl'', meaning "a man of noble birth or rank". The word is cognate with the Scandinavian form ''jarl'', and meant "chieftain", particular ...

felt that this species was uniquely distinct from the rest of ''Tetraplasandra'', so he erected a new genus for it, ''Munroidendron'', in 1952.''Munroidendron'' in International Plant Names Index. (see ''External links'' below). The genus was named for

George Campbell Munro George Campbell Munro (10 May 1866 – 4 December 1963) was a New Zealand born pioneer of Hawaiian botany and ornithology. He settled on a ranch in Lanai and wrote one of the first books on the birds of Hawaii, many species of which are now extinct ...

(1866-1963), described by

Umberto Quattrocchi Umberto is a masculine Italian given name. It is the Italian form of Humbert. People with the name include: * King Umberto I of Italy (1844–1900) * King Umberto II of Italy (1904–1983) * Prince Umberto, Count of Salemi (1889–1918) * Umberto ...

as "a pioneer in Hawaiian ornithology, botany, and horticulture; plant collector in the Hawaiian Islands".Umberto Quattrocchi. 2000. ''CRC World Dictionary of Plant Names'', volume III. CRC Press: Baton Rouge, New York, London, Washington DC. (vol. III). (see ''External links'' below). ''Dendron'' is a Greek word for "tree". Munro was apparently the first collector to see his eponymous genus, ''Munroidendron''.Earl Edward Sherff. 1952. "''Munroidendron'', a new genus of Araliaceous trees from the island of Kauai". ''Botanical Leaflets'' 7(section V):21-24. published by the author. Sherff separated ''Munroidendron'' from ''Tetraplasandra'' on the basis of five characters: the absence of umbellules, the

arrangement In music, an arrangement is a musical adaptation of an existing composition. Differences from the original composition may include reharmonization, melodic paraphrasing, orchestration, or formal development. Arranging differs from orches ...

of the flowers in a

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

, the sunken, diamond-shaped

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

scars, the long, persistence of the subtending floral

bract In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

s, and the

insertion Insertion may refer to: *Insertion (anatomy), the point of a tendon or ligament onto the skeleton or other part of the body *Insertion (genetics), the addition of DNA into a genetic sequence *Insertion, several meanings in medicine, see ICD-10-PCS ...

of the

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s in only one

whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

, even when numerous. It has been shown that, in spite of its appearance, the inflorescence is not truly a raceme because it is

determinate In logic and philosophy (especially metaphysics), a property is a characteristic of an object; a red object is said to have the property of redness. The property may be considered a form of object in its own right, able to possess other propertie ...

. Sherff divided the species now known as ''Polyscias racemosa'' into three varieties: var. racemosa, var. forbesii, and var. macdanielsii. These have been described as "not sufficiently distinct to be retained". The establishment of ''Munroidendron'' was contentious from the beginning.

William R. Philipson William is a masculine given name of Norman French origin.Hanks, Hardcastle and Hodges, ''Oxford Dictionary of First Names'', Oxford University Press, 2nd edition, , p. 276. It became very popular in the English language after the Norman conqu ...

said that ''Munroidendron'' "comprises a single species with such a distinct inflorescence and

corolla Corolla may refer to: *Corolla (botany), the petals of a flower, considered as a unit *Toyota Corolla, an automobile model name * Corolla (headgear), an ancient headdress in the form of a circlet or crown * ''Corolla'' (gastropod), a genus of moll ...

that it can well claim generic status.William R. Philipson. 1970. "A redefinition of ''Gastonia'' and related genera (Araliaceae)". ''Blumea'' 18(2):497-505. In 1971, a

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

study indicated that ''Munroidendron'' might be embedded in ''Tetraplasandra''.Charles C. Tseng. 1971. "Light and Scanning Electron Microscopic Studies on Pollen of ''Tetraplasandra'' (Araliaceae) and Relatives". ''American Journal of Botany'' 58(6):505-516. This result was not supported by

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

based on

DNA sequence DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. Th ...

s of

nuclear Nuclear may refer to: Physics Relating to the nucleus of the atom: * Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear ...

and

chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in ...

DNA regions. These studies show that '' Polyscias sandwicensis'' (formerly '' Reynoldsia sandwicensis'' is not most closely related to other species of '' Reynoldsia'', but is sister to ''Polyscias racemosa'', (formerly ''Munroidendron'').Annemarie Costello and Timothy J. Motley. 2007. "Phylogenetics of the Tetraplasandra Group (Araliaceae) Inferred from ITS, 5S-NTS, and Morphology". ''Systematic Botany'' 32(2):464-477. This pair is then sister to a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

Tetraplasandra ''Tetraplasandra'' is a no longer recognised genus of plants in the ivy family, Araliaceae. They are small to medium trees, (rarely shrubs or large trees) of mesic to wet forests.Porter P. Lowry II. 1990. "Araliaceae", pages 224-237. In: Warren L ...

'' in the sense of Philipson (1970). This pair of species and the nine species formerly in ''Tetraplasandra'' form a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

and comprise all of the Hawaiian species of ''Polyscias''. The 11 species of this "Hawaiian clade" and 10 species from Malesia, Melanesia, and southern Polynesia constitute ''Polyscias'' subgenus Tetraplasandra.

Description

Habitat and range

History

References

External links