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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