Aptandraceae Miers (1853)

Genera Included: Anacolosa (Blume) Blume, Aptandra Miers, Cathedra Miers, Chaunochiton Benth., Harmandia Baillon, Hondurodendron Ulloa, Nickrent, Whitefoord, and Kelly, Ongokea Pierre, and Phanerodiscus Cavaco.

Habit: Terrestrial trees and shrubs.

Parasitism: Positive evidence for parasitism (i.e. presence of functional haustoria) does not yet exist.  Taking into account the position of the family on molecular phylogenetic trees (see Malécot and Nickrent 2008), and assuming that parasitism has arisen once in Santalales and has since not been lost, it is expected that members of this family are root parasites. Reed (1955, p. 38) states that Aptandreae are root parasites, but no citation is given.

Roots: no data.

Stem: Twig tomentum none (glabrous) or with simple hairs.

Leaves: Leaves simple, alternate, with developed blades and petioles, exstipulate.  Secondary venation brochidodromous, tertiary venation reticulate, quarternary venation (aerolation) of polygonal meshes.  Unicellular hairs present or absent.

Leaf anatomy: Leaf unicellular hairs absent or present.  Epidermal and guard cell lignification none or weak.  Guard cell lumina narrow and wide, cuticular ledges inconspicuous and thick.  Stomata paracytic. Schizogenous cavities in leaf absent.  Leaf laticiferous channels absent or present.  Druses in epidermal cells absent.  Silicified walls of mesophyll and epidermal cells absent or present.  Mesophyll sclereids absent or present.  Leaf cystoliths absent.  Petiole and median vein sclerenchyma fibers and astroslereids absent or present.   Vascularization of the nodes unilacunar.  Basal and distal petiole as well as median vein vascularization a simple bundle.

Wood anatomy: Vessel grouping solitary and grouped in multiples.  Perforation plate type scalariform.  Vessel member length over 900 um.  Intervascular pits alternate.  Vascular tracheids assoc. w/ vessels present.  Fiber tracheids and libriform fibers present.  Axillary parenchyma abundant, strand width less than 7 cells and more than 7 cells.  Rays with all cells procumbent (homogeneous) and heterocellular, one row of erect cells.  Ray height long, over 1000 um and short, below 1000 um.  Wood cystoliths absent.  Silica bodies in ray cells absent. 

Inflorescence: Various; axillary clusters or fascicles (Anacolosa, Cathedra, Phanerodiscus), panicles (Aptandra, Ongokea), and short, corymb-like panicles (Chaunochiton).

Plant Sex: Flowers bisexual or plants dioecious (Harmandia and Hondurodendron).

Flowers: Bisexual or unisexual, actinomorphic, dichlamydous, hypogynous, 4-5 (6, 8) - merous.

Fruit: A drupe or nut, enclosed in the accrescent calyx in Aptandra, Chaunochiton, Ongokea, Harmandia and Hondurodendron, the disk in Anacolosa and Cathedra, and by the festoons in Phanerodiscus. Lipids and starch either present or absent. 

Seed: With fleshy endosperm, tiny embryo positioned at one end. Commercially valuable seed oils are present in Ongokea. Seedling with epigeal germination in Ongokea.

Chromosomes: No chromosome numbers reported for the family.

Alternate (synonymous) family names: Cathedraceae van Tieghem, Chaunochitonaceae van Tieghem, Harmandiaceae van Tieghem.

SIUC / College of Science / Parasitic Plant Connection / Aptandraceae / Description
URL: http://www.parasiticplants.siu.edu/Aptandraceae/description.html
Last updated: 18-Oct-10 / dln