The families of flowering plants

L. Watson and M.J. Dallwitz

Alseuosmiaceae Airy Shaw

Habit and leaf form. Shrubs (often of pittosporaceous appearance). Leaves alternate (to sub-opposite), or whorled (pseudowhorls of 3, 4 or 5); when alternate, spiral; not gland-dotted; simple. Lamina entire. Leaves exstipulate. Lamina margins sinuous dentate, or entire.

Leaf anatomy. Stomata present; anomocytic. Lamina without secretory cavities.

Axial (stem, wood) anatomy. Cork cambium present; initially superficial. Secondary thickening developing from a conventional cambial ring.

The wood ring porous. The vessel end-walls scalariform, or scalariform and simple. The axial xylem with tracheids; including septate fibres.

Reproductive type, pollination. Plants hermaphrodite, or polygamomonoecious (? — ‘polygamous’). Floral nectaries present. Nectar secretion from the disk.

Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’ (axillary and solitary or fasciculate, rarely in racemes or subterminal); when solitary, (sub) terminal, or axillary; when aggregated, in racemes, or in fascicles. Inflorescences (sub) terminal, or axillary. Flowers sometimes fragrant; regular; (4–)5(–7) merous. Free hypanthium present, or absent.

Perianth with distinct calyx and corolla; 8–14; 2 whorled; isomerous. Calyx (4–)5(–7); 1 whorled; polysepalous; valvate, or open in bud. Corolla (4–)5(–7); 1 whorled; gamopetalous; valvate; urceolate, or funnel-shaped.

Androecium (4–)5(–7). Androecial members free of the perianth, or adnate (to the corolla tube); all equal, or markedly unequal (two sometimes larger); free of one another. Androecium exclusively of fertile stamens. Stamens (4–)5(–7); isomerous with the perianth; oppositisepalous. Anthers dorsifixed; not becoming inverted during development; non-versatile; dehiscing via longitudinal slits; introrse. Pollen grains aperturate; 3 aperturate; colporate.

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 2 celled. Gynoecium syncarpous; eu-syncarpous; partly inferior to inferior. Ovary 2 locular. Epigynous disk present (flat or tumid, crowning the ovary). Gynoecium stylate. Styles 1; apical. Stigmas 1; more or less 2 lobed; clavate, or capitate. Placentation axile. Ovules 1–50 per locule (to ‘many’). Antipodal cells formed; 3; not proliferating.

Fruit fleshy; indehiscent; a berry. Dispersal unit the fruit. Seeds endospermic. Cotyledons 2.

Physiology, phytochemistry. Iridoids not detected (S.R. Jensen, unpublished).

Geography, cytology. Paleotropical and Antarctic. Frigid zone and tropical. New Caledonia, New Zealand.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Corniflorae; Cornales. Cronquist’s Subclass Rosidae; Rosales. APG III core angiosperms; core eudicot; Superorder Asteranae; campanulid. APG IV Order Asterales.

Species 11. Genera 3; Alseuosmia (Periomphale, Memecylanthus), Crispiloba, Wittsteinia.

Illustrations. • Alseuosmia linariifolia: Hooker, Fl. Novae-Zelandiae (1853). • Alseuosmia macrophylla: Hooker, Fl. Novae-Zelandiae (1853). • Alseuosmia macrophylla: Bot. Mag. 113 (1887). • Alseuosmia banksii: Hooker, Fl. Novae-Zelandiae (1853).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 15th April 2018.’.