Coulaceae Tiegh.

Genera Included: Coula Baillon, Minquartia Aublet., Ochanostachys Masters.

Habit: Terrestrial evergreen trees. Ochanostachys can reach 50 m in height.

Parasitism: The presence or absence of haustoria have not been reported for these three genera.  Germination studies of Ochanostachys by Ping (1997) did not report haustoria for plants up to three years old.  This and the topology of the molecular tree suggest that the entire family is nonparasitic (Malécot and Nickrent 2008).

Roots: no information.

Stem: pubescent when young, glabrous when older.

Wood anatomy: Vessel grouping solitary.  Perforation plate type simple.  Vessel member length below 900 um.  Intervascular pits alternate.  No vascular tracheids associated with vessels.  Libriform fibers present.  Axillary parenchyma abundant.  Axial parenchyma strand width more than 7 cells.  Rays heterocellular, in several rows of erect or square marginal cells.  Ray height long, over 1000 um.  Wood cystoliths absent.  Silica bodies not present in ray cells. Milky latex in sap of Minquartia.

Leaves: Alternate, simple, entire, petiolate, ovate-elliptic, apex acuminate; secondary venation eucamptodromous. Petiole canaliculate, often swollen at junction with blade (sometimes apparent only in older or larger leaves).

Leaf anatomy: Unicellular hairs absent.  Epidermal cells lignified.  Guard cells not lignified.  Lumina of guard cells narrow and wide.  Cuticular ledges of guard cells thick.  Stomata paracytic (not cyclocytic or anisocytic).  Schizogenous cavities in leaf present.  Laticiferous channel in leaf present.  Druses absent from epidermal cells.  Walls of mesophyll and epidermal cells not silicified.  Mesophyll sclereids absent.  Leaf cystoliths absent.  Petiole and midrib sclerenchyma fibers and astrosclereids present.  Midrib with complex vascular cylinder. Node vascularization trilacunar.  Basal petiole with a interrupted or continuous vascular cylinder.  Distal and median petiole vascularization simple or a complex vascular cylinder. 

Inflorescence: Axillary racemes or panicles. Inflorescence axes (peduncles and pedicels) usually tomentose with rusty brown trichomes. 

Plant Sex: Flowers bisexual.

Flowers: actinomorphic, dichlamydous, hypogynous.

Fruit: Subglobose to ovoid drupes with a thin pericarp and woody endocarp.

Seed: Subglobular, with oily and/or starchy endosperm.

Chromosomes: no chromosome numbers have been reported.

SIUC / College of Science / Parasitic Plant Connection / Coulaceae / Description
Last updated: 17-Jun-10 / dln