Drosanthemum Schwantes

Zeitschrift fur Sukkulentenkunde 3:14 (1927)
Name Status

Scientific Description

Family Aizoaceae.

Habit and leaf form. Herbs. Leaves well developed. Plants succulent. Perennial. Leaves cauline. Plants with neither basal nor terminal concentrations of leaves. Young stems cylindrical. Stem internodes solid. Xerophytic. Leaves minute to medium-sized; opposite, or whorled (clustered on short shoots, ‘indeterminate’); fleshy; imbricate to not imbricate; shortly petiolate, or subsessile; connate; simple; epulvinate. Leaf blades entire. Leaves with stipules, or without stipules. Leaf blade margins entire. Vegetative buds not scaly. Leaves without a persistent basal meristem. Leaf anatomy. Hairs present (glaucous or densely papillose). Urticating hairs absent. Stem anatomy. Secondary thickening absent, or anomalous.

Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Entomophilous (diurnal).

Inflorescence and flower features. Flowers solitary (flowers on erect, short shoots); pedicellate; ebracteate; ebracteolate; small, or medium-sized; regular; cyclic; pentacyclic to polycyclic. Free hypanthium present; includes calyx, staminodes and stamens. Perianth sepaline (with colourful, conspicuous staminodal ‘petals’); (1–)4–5(–20), or 20–120 (if the staminodes are interpreted as petals). Calyx present; 5; 1 -whorled; gamosepalous; imbricate; regular; fleshy; persistent. Corolla absent. Androecial members indefinite in number. Androecium 50–200 (i.e. to ‘many’, by branching). Androecial members branched (by dédoublement). Androecial sequence determinable, or not determinable. Androecial members maturing centrifugally; all equal; free of one another; 1–16 -whorled (i.e to ‘many whorls’). Androecium including staminodes. Staminodes 20–50 (many staminodes that are petal-like and white); petaloid. Stamens 20–100 (many); all more or less similar in shape (staminodes vary from stamens); reduced in number relative to the adjacent perianth (rarely), or isomerous with the perianth, or diplostemonous to polystemonous; staminodes outside stamens; filantherous. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Pollen shed as single grains. Gynoecium 5 carpelled. The pistil 5 celled. Gynoecium syncarpous; synovarious; inferior. Ovary plurilocular; 5 locular. Gynoecium stylate. Styles 5; free. Stigmas 5. Placentation parietal. Ovules 20–50 per locule (many); anatropous, or campylotropous.

Fruit and seed features. Fruit non-fleshy; dehiscent (dehisces when wet); a capsule; 5 celled; 20–100 seeded (many). Seeds non-endospermic. Perisperm present (mealy). Embryo well differentiated. Cotyledons 2. Embryo curved.

Additional comments. Low trailing hirsute stems.

Etymology. From the Greek drosos (dew) and anthemon (flower), referring to the glistening appearance of the flowers.

J. Gathe and Leslie Watson, 8 September 2016

Taxonomic Literature

  • Wheeler, Judy; Marchant, Neville; Lewington, Margaret; Graham, Lorraine (2002). Flora of the south west, Bunbury, Augusta, Denmark. Volume 2, dicotyledons. Australian Biological Resources Study. Canberra.
  • Blackall, William E.; Grieve, Brian J. (1988). How to know Western Australian wildflowers : a key to the flora of the extratropical regions of Western Australia. Part I : Dicotyledons (Casuarinaceae to Chenopodiaceae). University of W.A. Press. [Perth].
  • Australia. Bureau of Flora and Fauna (1984). Flora of Australia. Volume 4, Phytolaccaceae to Chenopodiaceae. Australian Govt. Pub. Service. Canberra.