Osmoxylon

 Osmoxylon novoguineense, photographed by Karl Gercens.

Belongs within: Araliaceae.

Osmoxylon is a genus of about fifty species of trees and shrubs found on the islands of south-east Asia, Micronesia and Melanesia. Flowers are produced in umbels with the central stalk producing sterile, berry-like ‘pseudofruits’; pollination of fertile flowers is believed to be effected by birds picking up pollen as they feed on these pseudofruits.

Characters (from Philipson 1995): Unarmed, glabrous or tomentose. Leaves palmately lobed or simple. Petiole base sheathing, ligulate, usually with one to several crests. Inflorescence a terminal compound umbel; rays each ending in three branches; central branch bearing a head or umbellule of sterile berry-like pseudofruits; lateral branches bearing a head or umbellule of hermaphrodite flowers, each pedicel not articulated below the flower. Calyx a rim or absent. Corolla lobed above, tubular below. Stamens 4-30. Ovary inferior, 1-many-locular. Fruit a fleshy drupe with 1-many compressed pyrenes.

<==Osmoxylon
    |--O. amboinense Miq. 1863P95
    |--O. arrhenicum Conn & Frodin 1995CF95
    |--O. boerlagei (Warb.) Philipson 1976 (see below for synonymy)P95
    |--O. chrysanthum Conn & Frodin 1995CF95
    |--O. confertiflorum Conn & Frodin 1995CF95
    |--O. corneri Conn & Frodin 1995CF95
    |--O. ellipsoideum Conn & Frodin 1995CF95
    |--O. geelvinkianum Becc. 1877 (see below for synonymy)P95
    |--O. insidiator Becc. 1877 (see below for synonymy)P95
    |--O. lanceolatum Philipson 1976P95
    |--O. micranthum (Harms) Philipson 1976 (see below for synonymy)P95
    |--O. miquelii Boerl. 1887 [incl. Gastonia simplicifolia Zipp. ex Boerl. 1887]P95
    |--O. novoguineense (Scheff.) Becc. 1877CF95 (see below for synonymy)
    |--O. pfeilii (Warb.) Philipson 1976 [=Eschweileria pfeilii Warb. 1891, Boerlagiodendron pfeilii (Warb.) Harms 1894]P95
    |--O. pseudofoliatum Conn & Frodin 1995CF95
    |--O. puniceopolleniferum (Stone) Stone 1983 [=Boerlagiodendron puniceopolleniferum Stone 1962]CF95
    |--O. reburrum (Stone) Stone 1983 [=Boerlagiodendron reburrum Stone 1962]CF95
    |--O. rectibrachiatum Conn & Frodin 1995CF95
    |--O. russellense (Philipson) Stone 1983 [=Boerlagiodendron russellense Philipson 1951, B. russellensis]CF95
    |--O. sessiliflorum (Laut.) Philipson 1976 [=Boerlagiodendron sessiliflorum Laut. 1910]P95
    |--O. spathipedunculatum (Philipson) Philipson 1976CF95 [=Meryta spathipedunculata Philipson 1951P95]
    |--O. striatifructum Conn & Frodin 1995CF95
    |--O. superantiflorum Conn & Frodin 1995CF95
    |--O. tetrandrum (Walker) Stone 1983 [=Boerlagiodendron tetrandrum Walker ex White 1950]CF95
    `--O. whitmorei Conn & Frodin 1995CF95

Osmoxylon boerlagei (Warb.) Philipson 1976 [=Eschweileria boerlagei Warb. 1891, Boerlagiodendron boerlagei (Warb.) Harms 1920; incl. B. warburgii Harms 1894]P95

Osmoxylon geelvinkianum Becc. 1877 [=Eschweileria geelvinkianum (Becc.) Boerl. 1886; incl. E. elegans Ridl. 1916, Boerlagiodendron elegans (Ridl.) Harms 1920, B. stenolobum Harms 1920]P95

Osmoxylon insidiator Becc. 1877 [=Boerlagiodendron insidiator (Becc.) Harms 1894, Eschweileria insidiatrix (Becc.) Boerl. 1886; incl. Osmoxylon carpaphagarum Becc. 1877, Boerlagiodendron carpaphagarum (Becc.) Harms 1894, Eschweileria carpaphagarum (Becc.) Boerl. 1886, B. pachycephalum Harms 1910]P95

Osmoxylon micranthum (Harms) Philipson 1976 [=Boerlagiodendron micranthum Harms 1920; incl. Eschweileria gawadensis Baker 1923, B. sayeri Harms 1920, B. tricolor Philipson 1951]P95

Osmoxylon novoguineense (Scheff.) Becc. 1877CF95 [=Trevsia novo-guineensis Scheff. 1876P95, Boerlagiodendron novoguineense (Scheff.) Harms 1894P95, Eschweileria novoguineensis (Scheff.) Boerl. 1886P95; incl. B. lauterbachii Harms 1900P95]

*Type species of generic name indicated

References

[CF95] Conn, B. J., & D. G. Frodin. 1995. Appendix: Species of Osmoxylon (Araliaceae) in the Solomon Islands (with additional notes on New Guinean species). In: Conn, B. J. (ed.) Handbooks of the Flora of Papua New Guinea vol. 3 pp. 271–285. Melbourne University Press: Carlton (Australia).

[P95] Philipson, W. R. 1995. Araliaceae (excluding Schefflera). In: Conn, B. J. (ed.) Handbooks of the Flora of Papua New Guinea vol. 3 pp. 1–48. Melbourne University Press: Carlton (Australia).

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