Key to the Species of Arum


Based on Boyce, 1989

Click on 📌 to highlight and compare characteristics.
Click on the line numbers to select characteristics.



1A. Tuber rhizomatous .. 2
2A. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. massively conic-cylindric, more than 1/2 to subequal to the spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 📌Arum concinnatum
2B. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. +/- slender-clavateClavate: Club-shaped; thicker at the apex than at the base. , 1/4-1/2 length of the spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 3
3A. Staminate flowers yellow prior to anthesisAnthesis: The period during which pollen is presented and/or the stigma is receptive. ; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s and pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s yellow .. 📌Arum italicum
3B. Staminate flowers purple prior to anthesisAnthesis: The period during which pollen is presented and/or the stigma is receptive. ; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s and pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s purple .. 4
4A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb pale green ? stained pale purple-green; leaves weakly hastateHastate: .. 📌Arum byzantinum
4B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb greenish white; leaves sagittateSagittate: -hastateHastate: .. 📌Arum maculatum
1B. Tuber discoid .. 5
5A. PistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s and/or staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s present .. 6
6A. Plant flowering in the autumn; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s present, pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s absent .. 📌Arum pictum
6B. Plant flowering in the spring; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s and pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s present .. 7
7A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior distinctly blotched and spotted purple .. 📌Arum dioscoridis
7B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior +/- unicolorous .. 8
8A. StaminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s and pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s subulate .. 9
9A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb ellipticElliptic: -ovateOvate: ; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. clavateClavate: Club-shaped; thicker at the apex than at the base. , long-stipitateStipitate: Having a stalk or stem. , c. 1/2 spatheSpathe: A large sheathing bract enclosing the flower cluster. length .. 📌Arum nigrum
9B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb lanceolateLanceolate: ; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. stoutly cylindrical, shortly stipitateStipitate: Having a stalk or stem. , more than A to subequal to spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 📌Arum palaestinum
8B. StaminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s and pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s filiform or aristate .. 10
10A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. tube interior distinctly bicolored, purple above, pale green to white below .. 11
11A. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. strongly clavateClavate: Club-shaped; thicker at the apex than at the base. , inflorescence sweetly scented .. 📌Arum gratum
11B. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. stout to slender-cylindric, inflorescence foetid .. 12
12A. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. stout-cylindric, subequal to spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 📌Arum elongatum subsp. elongatum
12B. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. slender-cylindric, up to 3/4 as long as the spatheSpathe: A large sheathing bract enclosing the flower cluster. limb 13
13A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior pale green suffused pale to mid-purple .. 14
14A. Ovaries stained purple apicalApical: Of, relating to, or denoting an apex. ly, spatheSpathe: A large sheathing bract enclosing the flower cluster. limb evenly suffused pale purple; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s in 2 whorls, pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s in 3-4 whorls .. 📌Arum orientale
14B. Ovaries concolorous pale green, spatheSpathe: A large sheathing bract enclosing the flower cluster. limb margins and apexApex: End forming a point. midgreen, centre purple; staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s in 3-4 whorls, pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s in 1-2 whorls .. 📌Arum apulum
13B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior rosy or crimson .. 15
15A. Plant robust; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb rosy .. 📌Arum cyrenaicum
15B. Plant delicate; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb crimson .. 📌Arum elongatum subsp. alpinariae
10B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. tube interior +/- unicolorous .. 16
16A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. tuber interior greenish white, sometimes flushed pale purple above and along the margins .. 17
17A. Inflorescence borne above the foliage .. 18
18A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb ellipticElliptic: ; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. long-stipitateStipitate: Having a stalk or stem. , clavateClavate: Club-shaped; thicker at the apex than at the base. .. 📌Arum alpinum
18B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb lanceolateLanceolate: to linearLinear: -lanceolateLanceolate: ; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. short-stipitateStipitate: Having a stalk or stem. or sessileSessile: Attached directly by its base without a stalk or peduncle. , cylindrical .. 19
19A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior mid-green .. 📌Arum korolkowii
19B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior purple or, rarely, greenish white with a thin purple border .. 20
20A. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. slender-cylindric, tapering basalBasal: Forming or belonging to a bottom layer or base. ly, sessileSessile: Attached directly by its base without a stalk or peduncle. ; pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. and staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. bases verrucate, purple .. 📌Arum jacquemontii
20B. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. conic-cylindric, sometimes massively so; pistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. and staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. bases +/- smooth, pale green to cream .. 📌Arum rupicola
16B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. tube interior deep purple .. 21
21A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb deep purple .. 📌Arum purpureospathum
21B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. limb pale green .. 22
22A. Inflorescence borne below the foliage; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb with a 1-1.5 mm wide purple border; leaves with basalBasal: Forming or belonging to a bottom layer or base. lobes more than a 1/3 as long as laminaLamina: Leaf blade. .. 📌Arum hygrophilum
22B. Inflorescence borne above the foliage; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb with a 2.5-3 mm wide purple border; leaves with basalBasal: Forming or belonging to a bottom layer or base. lobes less than a 1/4 as long as laminaLamina: Leaf blade. .. 📌Arum euxinum
17B. Inflorescence borne below the foliage .. 23
23A. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. very slender, subequal to longer than the spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 📌Arum lucanum
23B. SpadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. stout, shorter than the spatheSpathe: A large sheathing bract enclosing the flower cluster. limb .. 24
24A. Leaves c. 2/3 as broad as long; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior purple, exterior pale green; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. purple .. 📌Arum balansanum
24B. Leaves c. 1/4 as broad as long; spatheSpathe: A large sheathing bract enclosing the flower cluster. limb interior and exterior pale greenish white; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. pale brown .. 📌Arum hainesii
5B. PistillodePistillode: A sterile vestigial pistil remaining in a staminate flower. s and staminodeStaminode: A sterile or abortive stamen, frequently resembling a stamen without its anther. s absent .. 25
25A. SpatheSpathe: A large sheathing bract enclosing the flower cluster. cream to pale yellow, limb reflexing at maturity; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. mid to dark yellow, sweetly scented .. 📌Arum creticum
25B. SpatheSpathe: A large sheathing bract enclosing the flower cluster. white, limb erect and cucculate at maturity; spadixSpadix: A spike of minute flowers closely arranged around a fleshy axis and typically enclosed in a spathe. appendixAppendix: Sterile appendage at the end of a spadix. deep purple, scentless .. 📌Arum idaeum
 


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