Santalaceae

Genera Included: Based upon molecular and morphological evidence summarized in Nickrent et al. (1996), Eremolepidaceae (Antidaphne, Eubrachion, Lepidoceras) is not monophyletic but is one of the components of a paraphyletic Santalaceae. Even when more broadly circumscribed, Santalaceae is also not monophyletic. The family will be retained for the present until more natural units are defined.

Genera included: Acanthosyris (Eichl.) Griseb., Amphorogyne Stauffer & Hürlimann, Anthobolus R. Brown, Antidaphne Poeppig & Endlicher, Arjona Cav., Buckleya Torrey, Cervantesia Ruiz & Pavon, Choretrum R. Brown, Cladomyza Danser, Colpoon P. Bergius , Comandra Nutt., Daenikera Hürl & Stauffer., Dendromyza Danser., Dendrotrophe Miq., Dufrenoya Chatin., Eubrachion Hooker f., Exocarpos Labill. , Geocaulon Fern. , Hylomyza Danser., Jodina Hook. & Arn. ex Meissner, Kunkeliella Stearn, Lepidoceras Hooker f., Leptomeria R. Brown, Mida Cunn. ex Endl., Myoschilos Ruiz & Pav., Nanodea Banks ex Gaertner f., Nestronia Raf., Okoubaka Pellegrin & Normand, Omphacomeria (Endl.) A. DC., Osyridocarpus A. DC., Osyris L., Phacellaria Benth., Pyrularia Michx., Quinchamalium Molina, Rhoiacarpos A. DC., Santalum L., Scleropyrum Arnott., Spirogardnera George, Thesidium Sond., Thesium L.

Habit: Terrestrial small trees, shrubs, perennial herbs.

Parasitism: All (?) hemiparasites on roots and occassionally stems (e.g. Dendrotrophe, Phacellaria, Exocarpos).

Roots: For aerial parasites, the haustorial endophyte resembles that found in mistletoes of the Viscaceae. Sandalwood oil is distilled from the roots of Santalum album.

Stem: Some genera with xeromorphic adaptations, some with thorns; often with groups of silicified cells in the parenchymatous tissues of the shoot and with solitary or clustered crystals of calcium oxalate in some of the parenchyma cells. Nodes unilacunar.

Leaves: Alternate or less commonly opposite, simple, entire, sometimes reduced to scales; commonly with groups of silicified cells in the mesophyll; stomates paracytic or anomocytic or of various unusual types.

Inflorescence: Of diverse sorts, often with dichasia axillary to each bract. Those taxa with opposite phyllotaxy also have terminal flowers (Visser 1981).

Plant Sex: Flowers bisexual or plants monoecious or dioecious

Flowers: Actinomorphic, monochlamydous (Cronquist says this probably represents the corolla, epigynous (or in Anthoboleae hypogynous), 1/2 epigynous, or perigynous.
Calyx: Not present
Corolla: Tepals distinct or forming a valvately (3) 4-5 (-8)-lobed often fleshy cup or tube.
Nectary: Intrastaminal, lobed, commonly surrounding or seated on the ovary or lining the lower part of the perianth tube.
Androecium: Stamens as many as and opposite the tepals, adnate at the filament base; anthers tetrasporangiate and dithecal, dehiscence by longitudinal slits or sometimes by a single apical pore. Hairs are often present at the back of the filaments where they meet the perianth.
Pollen: 2-3 nucleate, triaperturate, with various types of apertures (e.g. prismoidal shape with hexacolporate pollen).
Gynoecium: Compound ovary of (2) 3 (-5) carpels; superior, 1/2 inferior or inferior; with a simple, terminal style and capitate or lobed stigma; unilocular or lobed only at the base; erect, free-central placenta with 1-4 pendulous ovules (or in Exocarpos, a single, massive placental column with an embedded ovule).
Ovule: Anatropous (or hemitropous), unitegmic, tenuinucellar or not differentiated into nucellus and integuments.
Embryo, etc.: Embryo sac development monosporic (or seldom bisporic), Allium type in Buckleya; endosperm development cellular or less often helobial; In Quinchamalium, the female gametophyte divides to form the first transverse wall in endosperm haustorium development (Kuijt 1968).

Fruit: A nut or drupe, usually without any viscid tissue. Nut may be embedded in a brightly colored fleshy ectocarp (e.g. Colpoon) which attracts dispersal agents such as birds. In Exocarpos, the peduncle becomes fleshy and serves to attract dispersal agents.

Seed: Solitary, without a differentiated testa but may be covered by a layer of sclerified cells; embryo axile, straight, with 2 cotyledons surrounded by copious fleshy, oily or (in Thesium) starchy endosperm.

Chromosomes: X = 5,6,7, 12, 13 and higher numbers.

Link to Description in Delta (Santalaceae)

Link to Description in Delta (Eremolepidaceae)