Amphorogynaceae (Stauffer ex Stearn) Nickrent & Der

Genera included: Amphorogyne Stauffer & Hürlimann, Choretrum R. Brown, Daenikera Hürl & Stauffer, Dendromyza Danser, Dendrotrophe Miq., Dufrenoya Chatin., Leptomeria R. Br., Phacellaria Benth., Spirogardnera George. 

Habit: Root parasitic small trees and shrubs, shrubs simultaneously parasitic on roots and stems (amphiphagous), stem parasitic lianas (dendroparasites), and stem parasitic shrubs (mistletoes). The term dendroparasite was considered synonymous with mistletoe (an aerial parasite) by Macklin and Parnell (2002) but is used here in the sense of Vidal-Russell and Nickrent (2008) and Der and Nickrent (2008), i.e. a twining, stem parasitic liana that initially forms a primary haustorial connection to the host stem and then secondary haustoria via adventitious roots.  Phacellaria is a hyperparasite on Loranthaceae and other Amphorogynaceae.

Parasitism: parasitism in dendroparasites (Dendromyza, Dendrotrophe) and mistletoes (Dufrenoya, Phacellaria) is visually apparent; however, first documentation of this trophic mode appears to be with Danser (1939, 1940).  For the root parasites and amphiphagous parasites: Amphorogyne (Stauffer 1969), Choretrum (Rao 1942), Daenikera (Hürlimann and Stauffer 1957), Leptomeria (Herbert 1924-1925), and Spirogardnera (Stauffer 1968).

Roots: the haustoria of Choretrum were described in Rao (1942) but not illustrated or photographed. Hegmann and Weber (1990) conducted light and electron microscopy of the haustorium of Dendrotrophe buxifolia (as Henslowia buxifolia).  

Stem: with sympodial branching, in some aerial parasites differentiated into vegetative and haustorial shoots. Glabrous or pubescent.

Leaves:  alternate or subverticillate; either dimorphic or not; persistent, caducous or deciduous; developed with blade and petiole or as scales (squamate).

Inflorescence: various, axillary or terminal, including solitary flowers, monochasia, spikes, racemes, umbels and panicles. Floral and inflorescence trichomes absent or present.  Floral bracts and/or bracteoles separate or forming an involucre, either persistent, caducous or deciduous.

Plant Sex:  Plants with bisexual flowers or unisexual (then plants dioecious).

Flowers: pedicellate or flowers sessile. 

• Calyx: Absent (no calyculus either).
• Corolla: Petals 4-6, uncinate in some, occassionally with a short corolla tube. Tuft of corolla hairs behind the petals are present in most genera (except in Dendromyza and Phacellaria).
• Nectary: Glandular disk present on top of the inferior ovary, with or without lobes (or lobes obscure).
• Androecium: Stamens same number as petals. Filament very short, equal to or slightly shorter or longer than the anther.  Anther attachment dorsifixed or anther sessile; the condition "dorsi-basifixed was used by Stauffer to describe the condition in this family; anther 4-locular (tetrasporangiate), with anterior and posterior locules of either equal size (isomerous) or unequal (anisomerous).  Locules arranged parallel to filament (longitudinal) or divergent (horizontal) from filament, each opening individually.  The independent dehiscence of each thecal loculus (as opposed to a longitudinal slit common to both) was an  unusual feature that compelled Stauffer (1969) to recognize tribe Amphorogyneae.
• Staminodia: sometimes present (and pistillodes).
• Pollen: Stauffer and Hürlimann (1957) give a brief description of pollen from Amphorogyne celastroides.
• Gynoecium: Ovary position inferior (flower epigynous).  Locule number (semilocules) at base of ovary 1-6, unilocular above.  Style short cylindrical or short conical to absent.  The free-central placental column is straight (not twisted), sometimes extended apically beyond ovules to base of style.  Stigma 3- to 5-lobed.  In Phacellaria the style is hollow, opening directly into ovarian locule. 
• Ovule: 2-5, ategmic. 
• Embryo, etc.: Embryo sac sometimes extending beyond the ovule or placenta.  Suspensor present. Embryology of Leptomeria has been reported (Ram 1959).

Fruit:  Fruit a drupe or pseudodrupe, 3 cm or less in diameter, with a stony endocarp. Fruiting pedicel not thickened upwards or fleshy and swollen.  Mature fruit crowned by persistent perianth parts, not dehiscent.  In aerial parasites (Dendromyza, Dendrotrophe, Phacellaria), exocarp fibers form seed attachment structures.  Mesocarp fleshy and fibrous, forming seed attachment structures.  Endocarp wall texture crustaceus, bony, woody, or cartilaginous.  In some taxa endocarp dividing into segments, hence a pyrene with lobed seeds.

Seed: single per fruit.  Excellent drawings of the seeds from Dendromyza, Dufrenoya and Phacellaria in Plate XIV of Danser (1940). Kuijt (1990) examined the germination pattern in Phacellaria, Dendromyza and Dufrenoya (the "Henslowia" complex).

Chromosomes: none reported.

Alternate Family Names: none.