Morphological Parts
Fig. 1: page 228 of "Gardens' Bulletin Singapore v.50 (1998)"
Diagram of the Alocasia leaf blade
A - Anterior Lobe
B - Posterior Lobe
C - Anterior Costa
D - Posterior Costa
E - Primary Lateral Vein
F - Subsidiary Vein (with axillary gland)
G - Secondary Vein
H - Sector with interprimary collective vein formed by meeting of secondary veins
I - Sector with interprimary collective vein not formed
J - Axillary Gland
K - Intramarginal Vein
L - Inner side of posterior lobe
M - Petiole
N - Sinus
Fig. 2: Front view of an Alocasia scalprum inflorescence. PARC © 2022
Major parts of the Alocasia inflorescence (Left/Fig. 2)
A - Spathe (green)
Composed of the limb and lower spathe which initially covers the developing spadix.
B - Limb
Canoe-shaped, open part of the spathe.
C - Lower Spathe / Floral Chamber
Closed part of the spathe which covers the female flowers.
D - Spadix (white)
Supports the flowers, where pollination occurs.
E - Peduncle (inflorescence stalk)
Supports the spathe and spadix.
Regions of the Alocasia spadix (Right/Fig. 3)
A - Stipe
Supports the entire spadix.
B - Female Zone
Composed of the pistils.
C - Sterile Zone/Interstice
Composed of the neuter organs.
D - Male Zone
Composed of the synandria.
E - Appendix
The terminal part of the spadix.
Fig. 3: Side view of an Alocasia scalprum spadix (front facing left/ spathe opens at left side). PARC © 2022
Organs of the spadix
1 - Synandrium (Male)
fused anthers, where pollen is produced
2 - Neuter Organ (Sterile)
varies in many irregular shapes
3 - Pistil (Female)
composed of the ovary, style, and stigma
4 - The organs in scale (millimeters)
Parts of the pistil
A - Ovary
if pollinated, develops into a fruit bearing seed/s
B - Style
where pollen passes through after the stigma
C - Stigma
receives the pollen
Fig. 4: Close-up shots of the reproductive organs of an Alocasia boyceana. PARC © 2022
Neuter Organs of the Sterile Interstice
A - Free Staminoidal Neuter Organs (Basal)
As its name suggests, these neuter organs are irregular or free in form. These are usually found at the bottom part of the sterile interstice.
B - Connate Staminoidal Organs (Middle)
These are tubular in shape, or have a noticeable hole or slit at the center. These are usually located at the middle part of the sterile interstice.
C - Synandrodial Neuter Organs (Upper)
These neuter organs come in a wide variety of polygonal shapes. The edges/margins are sometimes crenate, the closer it is to the male zone above it. Usually found at the topmost part of the sterile interstice.
Fig. 5: Sterile Interstice from 3 distinct specimens of Alocasia boyceana. PARC © 2022
Fig. 6: Infructescence of an Alocasia boyceana. PARC © 2022
Infructescence
(Left/Fig. 6)
A - Ripe fruit with seed
B - Seedless fruits
C - Unpollinated pistils
D - Stipe
E - Peduncle
(Right/Fig. 7)
A - Fruit
B - Seed
Fig. 7: An Alocasia boyceana fruit and seed. PARC © 2022