Le Araceae mediterranee

Le Araceae sono diffuse in quasi tutto il mondo e quelle che vivono intorno al bacino del Mediterraneo rappresentano un gruppo di specie piuttosto vario ed interessante. Hanno però un aspetto ecologico in comune: la dormienza estiva.

Questa è dettata dal clima mediterraneo, anche se si manifesta pure in specie che raggiungono areali distanti dal nostro mare.

I generi sono:

  1. Ambrosina: 1 specie
  2. Arisarum: 3 specie
  3. Arum: 31 specie
  4. Biarum: 22 specie
  5. Dracunculus: 2 specie
  6. Eminium: 9 specie
  7. Helicodiceros: 1 specie

Ambrosina è un genere monotipico che annovera solo la specie Ambrosina bassii. Questa è caratterizzata da una delle infiorescenze più complesse di tutte le Araceae: ha la forma di una “barchetta” divisa internamente in due piani. Uno con qualche fiore maschile ed uno con un solo fiore femminile. Lo spadice è fuso con la spata e costituisce la parete di separazione tra i due piani. Il colore della spata è bruno-porpora con variegature che vanno dal nero al verde e le sue dimensioni sono di circa 2 cm. L’apice della spata è acuminato ed è ripiegato sopra il resto dell’infiorescenza. Le foglie sono ellittiche e possono essere variamente variegate di porpora, verde scuro o bianco. Esistono anche alcune forme a foglie lineari o completamente porpora. Preferisce i luoghi semiombreggiati e ben drenati. Fiorisce in inverno.

Ambrosina bassii

Arisarum è un genere rizomatoso e contiene la specie A. vulgare che è una pianta molto comune intorno al Mediterraneo. Le sue foglie sono variabili nella forma e nell’eventuale maculatura bianco-argentea. La spata è tubulare, eretta ma con l’apice ricurvo ed aperto verso il basso da cui fuoriesce l’appendice dello spadice. Esistono esemplari più o meno scuri nei colori della spata: da striata di verde e bianco con apice completamente verde a striata di marrone scurissimo e bianco con apice marrone scurissimo, talvolta con sfumature purpuree. Una specie (per qualcuno solo una sottospecie) simile ma più adatta ai climi più aridi e caldi del Mediterraneo è Arisarum simorrhinum, ha piccioli e peduncoli più corti ed un portamento più compatto. L’infiorescenza è simile a quella di A. vulgare, ma più breve, più scura e con l’appendice dello spadice molto clavato ed allargato verso l’apice. Un’altra specie del genere è Arisarum proboscideum, con una spata bianca alla base e quasi nera all’apice, lungamente caudata e molto tipica. Quest’ultima vive nei boschi freschi e ombrosi dell’Italia ed è una rarità. A. vulgare e A. simorrhinum fioriscono dall’autunno alla primavera, mentre A. proboscideum fiorisce in primavera.

Arisarum vulgare
Variabilità nelle foglie di Arisarum vulgare
Arisarum proboscideum

Arum è il genere più comune in Europa e quello che ha dato il nome alla famiglia. Contiene circa 31 specie, alcune a diffusione ristretta ed altre con ampi areali. Il genere si ritrova dalla Svezia meridionale all’Asia centrale, al Nord Africa ed alle Canarie ed ingloba completamente il Mediterraneo. alcune specie hanno tuberi discoidali, altre hanno rizomi tuberosi orizzontali. Nelle varie specie le spate sono vistose, dal bianco, al verde chiaro, al giallo, al quasi nero, passando per alcune specie con colori rossastri. In lunghezza si va da quelle di meno di 10 cm di Arum idaeum a quelle di quasi 40 cm di Arum purpureospathum. Le appendici degli spadici variano da circa 4 cm come in alcuni individui di Arum maculatum agli oltre 30 cm di alcuni individui di Arum rupicola. Fioriscono tutti da fine inverno a primavera, tranne A. pictum che fiorisce in autunno.

Il genere potrebbe probabilmente celare qualche nuova specie ancora non scoperta. Infatti, ad esempio, un mio amico di Facebook ha postato una foto di una specie mai vista che anche agli occhi di un tassonomista di fama mondiale pareva una nuova specie. Spero che qualcuno ci stia lavorando.

Clicca qui per una mia descrizione di tutte le specie del genere Arum (in inglese).

Arum purpureospathum
Arum purpureospathum
Arum apulum
Arum hygrophilum
Arum sintenisii
Arum palaestinum
Arum rupicola
Arum cylindraceum
Arum italicum
Arum idaeum
Arum idaeum
Arum idaeum, rara forma ad appendice dello spadice bianca
Arum concinnatum
Arum megobrebi
Arum orientale
Arum creticum
Arum cyrenaicum

Biarum è il secondo genere delle Araceae mediterranee come numero di specie. Comprende la specie B. tenuifolium che, con qualche sottospecie, è diffuso in quasi tutto il Mediterraneo meridionale. Le altre specie sono concentrate nel Mediterraneo orientale e nel Medio Oriente. Si tratta di specie più piccole di quelle del genere Arum. Le infiorescenze hanno spate la cui base si trova in posizione ipogea e variano da quelle a lembo disteso e acuto (solitamente bruno-nerastro e giallo solo in B. auraniticum) a quelle a lembo biancastro, avvolgente lo spadice e aperto solo lateralmente nella parte alta, a quella di B. ditschianum la cui spata è praticamente tutta sottoterra mentre la funzione attrattiva nei confronti degli impollinatori è svolta dall’appendice dello spadice, epigeo, che è un cono arrotondato di circa 3 cm di altezza per 2 cm di diametro basale, giallo uovo e molto vistoso.

Fioriscono dall’autunno alla primavera, a seconda delle specie.

Probabilmente in questo genere esistono specie non ancora scoperte, mentre una già scoperta deve ancora avere un nome.

Dracunculus ha solo due specie: D. vulgaris e D. canariensis. Il primo è diffuso un po’ in tutta l’area Mediterranea, ma probabilmente spontaneo solo intorno al Mar Egeo, ha un tubero verticale che cresce verso il basso, talvolta sbulbillante, ha foglie palmato-partite, spesso con macchie bianche; le infiorescenze sono costituite da un lembo della spata che può superare gli 80 cm di lunghezza, a forma triangolare, rosso scuro, con un’appendice dello spadice appuntita e quasi altrettanto lunga, rosso-nerastra. Può superare il metro di altezza ed è l’Aracea più grande del Mediterraneo. A Creta, in località piuttosto remote, esiste qualche popolazione con qualche esemplare a spata bianca e qualche esemplare con appendice gialla. Esistono anche individui intermedi, ma anche qui la maggioranza ha colorazioni normali.

Dracunculus canariensis è leggermente più piccolo, simile ma a spata candida, ad appendice gialla e a differenza dell’altra specie ha un odore gradevole.

Entrambe le specie fioriscono a primavera.

Dracunculus vulgaris, forma tipica
Dracunculus vulgaris, forma a spata bianca
Dracunculus vulgaris, forma a spata bianca ed appendice dello spadice gialla
Dracunculus vulgaris, forma rosea ed appendice dello spadice gialla
Dracunculus vulgaris, forma rosea
Dracunculus vulgaris, forma a spata quasi tutta bianca ed appendice dello spadice giallo-bronzea
Dracunculus vulgaris, forma a spata verdognola
Dracunculus vulgaris, forma a spata rosso-chiaro
Dracunculus vulgaris, forma verdognola ad appendice dello spadice giallo-verdastra

Eminium è un genere che cresce nelle steppe semidesertiche dal Medio Oriente all’Asia Centrale. Le specie, tutte tuberose, sono nove, le spate sono nerastre e in alcune specie le foglie hanno due orecchiette basali piegate perpendicolari rispetto al resto della lamina fogliare-, in altre sono ellittiche. Le foglie e le spate sono spesse o leggermente succulente.

Le spate hanno la loro base a livello del terreno ed i frutti si formeranno in tale posizione, come in Biarum.

In E. spiculatum il lembo della spata è tipicamente corrugato.

Helicodicerus è un genere monotipico e la sua unica specie, Helicodiceros muscivorus, è un endemismo di Sardegna, Corsica e Baleari. Forma un tubero che cresce verso il basso, le foglie sono glauche e possono essere con due orecchiette basali erette o lanceolate. La spata ha il lembo piuttosto rotondeggiante, di circa 15-20 cm, ripiegato in avanti e verso il basso, rosso-porpora-brunastro, peloso. L’appendice dello spadice è rosso-grigiastra ed anch’essa pelosa. Viene impollinato dalle mosche, poiché, come molte altre Araceae emette un odore di carne in putrefazione. Fiorisce a primavera.

Helicodiceros muscivorus

In coltivazione rappresentano un gruppo interessante e non sono generalmente molto difficili, purché tu dia loro un terreno ben drenato, un riposo estivo asciutto ed umidità invernale. Se le coltivi in vaso evita che esso sia colpito dal sole diretto durante la dormienza estiva poiché potrebbe scaldarsi troppo e, a inizio autunno, con le prime annaffiature potrebbero insorgere dei marciumi. Come rusticità ho sperimentato che anche a -4°C non subiscono danni, nemmeno in vaso, in cui prendono freddo da ogni lato. Durante le notti più fredde le foglie possono afflosciarsi, come se fossero state “lessate” dal gelo, per poi riprendersi e tornare come prima nel giro di poche ore. Nei climi più freddi potrai tenere le specie meno rustiche in serra. Mi piace la soluzione (nordica) di coltivarle in serra in vasi di terracotta immersi in letti di sabbia umida e pacciamate in superficie con della ghiaia fine: si attenuano così le variazioni di umidità e di temperatura nel suolo. Se vivi sul Mediterraneo ed hai un terreno non argilloso e ben drenato, anche se sassoso, potrai coltivarli senza problemi in piena terra limitandoti a tenere la zona priva di erbacce.

Alcune specie sono rare e se le coltivi, soprattutto se tenendone anche i dati di località, contribuirai a mantenere più elevato il numero di individui esistenti. Ho visto già troppe volte come diverse specie a distribuzione ridotta o puntiforme stiano rischiando l’estinzione per le attività umane.

Arum species list

Arum alpinariae

Tuber vertically arranged, discoid, about 5 cm in diameter and 2 cm in thickness. Petiole up to 45 cm in length. Leaves up to about 30 × 15 cm in size, hastate or oblong-hastate, pointed at the apex. Spathe about 15-25 cm in length, greenish-white to purplish outside, crimson red on the interior part of its limb. Spadix about as long as the spathe limb. Spadix appendix dark red, slender, clavate, stipitate, about ⅓ of the limb length. Staminodes and pistillodes white. The whole plant is about 30 cm in height. Endemic to an area in NW Turkey.

 

Arum apulum

Tuber discoid, vertical, up to 6 cm in diameter and 2.5 cm thick. Petioles about 15-30 cm long, purple at their base. Leaves hastate-sagittate, up to 16 × 13 cm. Peduncle about 5-10 cm long, purple. Spathe up to 18 cm long, greenish-purple to light brown outside; dark pink to purple on the inner limb, lighter at its base and sometimes at its margin too. Spadix with staminodes and pistillodes, slightly longer than the half of the limb. Appendix cylindrical-clavate, long stipitate, up to 4 cm in length, purple to brown, darker on the stipe. The inflorescence has a light odour of urine and horse dung. This species is endemic to central Apulia, Italy.

 

Arum balansanum

Tuber discoid, vertical, up to 6 cm in diameter and 2.5 cm in thickness. Petiole about 15-25 cm long. Leaves oblong-hastate, about 8-14 cm × 4-10 cm. Peduncle, about 15-25 cm. Spathe 9-14 cm in total length. Spathe limb lanceolate, acuminate, up to 10 × 3.5 cm in size, erect, greenish outside and greenish to purple inside. Spadix with staminodes and pistillodes, up to 7 cm long, with a clavate-subcylindrical appendix that is beige-pinkish to purple-brownish in colour and unclearly stipitate. The inflorescence has a smell of horse dung. W Turkey.

 

Arum besserianum

Tuber discoid. Petiole about 18-25 cm in length. Leaves sagittate or sagittate-hastate. Peduncle about 15 cm long, slightly shorter than the petiole. Spathe about 12 cm long, with a lanceolate-oblong, subacuminate limb. Spadix about 5-6 cm long, with 4 dense whorls of staminodes and with scarce pistillodes. Spadix appendix clavate-ellipsoid, with a long stipe. S Poland and NW Ukraine.

 

Arum byzantinum

Tuber horizontal, cylindrical, rhizomatous, about 2 cm in diameter and up to 7 cm long. Petiole about 15-50 cm long, purple at the base. Leaves hastate, variable in width/length ratio, rarely spotted with dark purple.

Peduncle 6-20 cm, usually more or less shorter than the leaves. Spathe 9-25 cm long, with an elliptic-lanceolate limb that is typically rather narrow, acute, 7-20 cm long and 2-8 cm wide. The limb is greenish stained with brownish-purple towards the margins, especially on the inner page, and its apex bends with age. Spadix up to 10 cm in length, never exceeding the half of the limb length, with pistillodes. Spadix appendix clavate rather slender, purple, with a long darker stipe. The inflorescence is slightly urine-smelling. Crete and E Balkans.

 

Arum concinnatum

This species has a horizontally oriented rhizomatous tuber that is 7-15 cm long and 1.5-3.5 cm in diameter. Petioles 20-45 cm long. Leaves sagittate-hastate or oblong-sagittate, up to 55 × 32 cm in size, with some silver-grey blotches above. Spathe carried by a short peduncle (never reaching 15 cm), with a strong urine scent. Spathe limb green edged with purple outside, while internally it is greenish-white, more or less flushed with pink towards the edge (rarely fully greenish or fully pink). Spadix 9-27 cm long, bearing staminodes and pistillodes, with a shortly stipitate, conic-cylindrical, large appendix (7-23 cm × 0.9-1.5 cm) that can vary in colour from pale to dull yellow and rarely to purple. It grows wild in the Aegean islands, the southernmost part of the Peloponnese, Crete and Cyprus.

 

Arum creticum

Tuber discoid, vertical. Leaves sagittate, variable, up to 25 × 18 cm. Total height up to about 55 cm. Spathe 15-25 cm, typically facing upwards, whitish to yellow. Spadix appendix yellow, tapered, often exceeding the recurved spathe. The inflorescence is scented and rarely contains a few sterile flowers, if any. This species grows wild in Crete, Karpathos and SW Turkey. A form from the Marmaris peninsula, Turkey has a dark red tint in the lower part of petioles and peduncles.

 

Arum cylindraceum

Tuber vertical, discoid, up to 5 cm in diameter and 2 cm in thickness. Petiole about 12-20 cm, sometimes purple at the base. Leaves sagittate or hastate-sagittate, about 9-13 × 3-7 cm in size, uniformly green. Peduncle reaching the leaf level or exceeding it, 12-18 cm long, sometimes purplish at the base. Spathe about 10-15 cm long. Spathe limb about 8 × 4 cm in size, elliptic-lanceolate, acuminate to almost caudate, completely greenish-white or with some purple shades towards the margins. Spadix slightly shorter than the spathe limb, with pistillodes and staminodes. Spadix appendix whitish-yellow to pinkish-yellow to purple, up to 5 × 0.4 cm, long stipitate, subcylindrical to clavate. This species has an unscented inflorescence. S Sweden to Crete and Portugal to Turkey.

 

Arum cyrenaicum

Tuberous species with a vertically orientated discoid tuber that can reach 5 cm in diameter and 2.5 cm in thickness. Petioles 5-27 cm long. Leaves broadly sagittate, up to 20 × 12 cm in size. Peduncle up to 11 cm long, never exceeding the leaves. Spathe up to 16 cm long, with an elliptic acuminate limb up to 12 × 5.5 cm that is interiorly pinkish to purple and paler towards its apex and towards its base, while externally it’s greenish shaded with purple near the margin. Spadix with staminodes and pistillodes, up to about 9 cm in length. Spadix appendix long stipitate and clavate-cylindrical, purple-brownish to olive green-yellow with a darker stipe, up to 6.5 cm long. The inflorescence has a light scent of horse dung. Its natural distribution ranges from SW Crete to NE Libya.

 

Arum dioscoridis

Tuber discoid, vertical, up to 10 cm in diameter. Petiole ranging from about 15 to 50 cm long. Leaves up to about 45 × 27 cm, hastate-sagittate. Peduncle 4-10 (42) cm long. Spathe 11-40 cm long (including the tube that can be up to 8 cm in length), whitish-green to purple, often with purple-black spots of variable diameter, especially towards its base. Spadix with staminodes and pistillodes, equaling or exceeding the half length of the spathe, 12-28 cm, with a massive, cylindrical, purple (rarely dull yellow) appendix that can be short- to long-stipitate. The inflorescence has a strong bad smell of carrion and dung and appears in late spring. Turkey, Cyprus to Iraq. Var. cyprium: spathe limb greenish-white, with blackish blotches that are gradually larger towards the base; var. philistaeum: spathe limb uniformly purple-red, sometimes with some darker blotches; var. syriacum: spathe limb pale green, with small light purple-brownish spots (sometimes with no spots).

 

Arum elongatum

Tuber discoid, vertical, about 5 cm in diameter and 2 cm in thickness. Petiole up to 45 cm in length. Leaves up to 32 × 21 cm in size, hastate, pointed at the apex. Spathe 15-27 cm in length, brownish-red, sometimes with a whitish spot in the centre. Spadix appendix about ⅔ of the limb length, purple-brown. Staminodes and pistillodes yellow, tinged with purple towards their tips. Spadix appendix cylindrical or slightly clavate, stipitate, massive. The whole plant is about 30 cm in height. The inflorescence is strongly smelling of urine and horse dung. It is distributed around the Black Sea where it grows in partially shaded forest edges and in full sun.

 

Arum euxinum

Similar to Arum hygrophilum but generally smaller. Petioles up to 45 cm long. Leaves up to 11 × 6 cm in size. Spadix with staminodes (ca. 4 whorls) and pistillodes (0-1 whorls). It mostly differs from Arum hygrophilum for the different quantity of staminodes and pistillodes whorls. It is distributed in the mountains of northern Turkey, along the Black Sea coast.

 

Arum gratum

Tuber discoid, vertical. Petiole 18-30 cm long, green. Leaves oblong-hastate to sagittate-hastate, up to 18 × 12 cm in size, rarely with some purplish-black spot. Peduncle fully underground or just 2-3 cm above soil. Spathe up to 18 cm long, whose tube is sometimes partially underground. Limb ovate-elliptic, up to 15 × 7 cm, acute-acuminate, greenish stained with pink outside and olive-green with some pinkish-purplish staining inside (sometimes with some additional blackish dot). Spadix about 6 cm long, with pistillodes and staminodes. Spadix appendix clavate and stipitate, about 4 cm in length, reddish to greenish, shaded with purple; stipe purple. The inflorescence in this species has a sweet odour. Mediterranean Asia.

 

Arum hainesii

Tuber discoid, vertical, up to 6 cm in diameter and 2.5 cm in thickness. Petiole about 50 cm long, typically paler at its base. Leaves distinctly hastate, up to about 30 × 22 cm in size. Peduncle not exceeding 10 cm in length. Spathe 15-25 cm long. Spathe limb up to 21 cm long, fully pale green in color, acuminate and erect. Spadix with staminodes and pistillodes, not reaching the half of the limb, with a cylindrical stipitate appendix that is about 5 cm long and light brown in colour. This species is native to Iraq.

 

Arum hygrophilum

Tuberous species. Tuber usually vertically orientated, discoid. Petioles up to 75 cm long. Leaves lanceolate-hastate, up to 45 × 15 cm in size. Spathe up to 14 cm in length, greenish, sometimes with purple edges, bent forwards at apex. Spadix 7.5-9.5 cm long, with staminodes (in 2-3 whorls) and pistillodes (in 2-3 whorls). Spadix appendix up to 3 mm in diameter, dark purple. It has a disjunct distribution, growing wild in Cyprus, Syria, Lebanon, Jordan, Israel and Morocco.

 

Arum idaeum

Tuber discoid, horizontally orientated, up to 5 cm in diameter and 2.5 cm in thickness, starting to sprout at the winter beginning. Leaves oblong-sagittate, up to 22 × 17 cm, dark green. Petiole about 10-20 cm long, strongly tinged with purple, especially towards its base. Peduncle shorter than the leaves or just equaling them, green-purplish. Spathe 8-13 cm long. Spathe limb lanceolate to elliptic, 5-9 cm long, acute to acuminate, erect, greenish-white outside and white with translucent blotches inside, thinly margined with purple. Spadix 8-9 cm long, without staminodes and pistillodes. Spadix appendix spindle-shaped, with a short and thick stipe, 6-7 cm long, dark purple, sometime marbled with lilac (rarely yellowish or white, sometimes marbled with pink). The inflorescence has no scent. Cretan mountains.

 

Arum italicum

Horizontal rhizomatous tuber, up to about 8 cm long and 3 cm in diameter. Petioles 15-40 cm long. Leaves 15-35 cm × 10-24 cm, hastate to sagittate, dark green, often with lighter markings, sometimes with white venation and/or with blackish-purple spots. Peduncle shorter than petioles. Spathe 15-40 cm long, green-yellowish to white; sometimes with a very thin purple margin, flushed with purple or purple-spotted. Spadix with staminodes and pistillodes, about 7-13 cm long, yellow (rarely purplish), stipitate, slightly clavate. Each fruit contains 3-4 seeds. S and W Europe, Canary Islands to Cyprus to S England. Subsp. neglectum: leaves plain green or with dark spots. Basal leaf lobes convergent or overlapping. Each fruit contains 1-2 seeds. W Europe. Subsp. albispathum: similar to subsp. neglectum but spathe white internally and green externally. Crimea and SW Asia.

 

Arum jacquemontii

Tuber discoid, vertical, up to 5 cm in diameter and 2.5 cm in thickness. Petiole 11-28 cm long, green tinged with purple. Leaves sagittate or sagittate-hastate, up to 30 × 12 cm. Peduncle up to 32 cm, longer than the leaves. Spathe about 15-20 cm in length. Limb elongated and acuminate, about 10-18 cm long, erect just after opening, then bent forwards, purplish-green outside, dark purple inside (still darker in the central area). Spadix almost as long as the limb, with purple-based staminodes and pistillodes. Appendix cylindrical, tapering at both ends, about 6 to 14 cm in length, brownish-yellow to brownish-purple and to purple, lighter in colour towards its base. The inflorescence has no scent. Southern central Asia to W China.

 

Arum korolkowii

Tuber discoid, vertical, sprouting at the winter beginning, up to 7 cm in diameter and 3 cm in thickness. Petiole 12-35 cm long, striped with brownish-green. Leaves sagittate-hastate to oblong sagittate, up to 16 × 13 cm in size. Peduncle longer than the leaves, 16-46 (60) cm long. Spathe up to 20 cm in length. Limb lanceolate, acuminate, elongated, fully green but sometimes lighter and/or flushed with purple internally. Spadix as long as the half to ⅔ of the limb, with green-based pistillodes and staminodes. Appendix spindle-shaped to clavate, with a short and broad stipe, cream to light reddish-brown, 9-10 cm in length, darkening towards its base. The inflorescence has no scent. Southern central Asia.

 

Arum lucanum

Tuber discoid, vertically arranged, up to 4 cm in diameter and 2.5 cm in thickness. Petioles up to 12 cm in length, green. Leaves ovate cordate to slightly hastate, acute, up to 12 × 5cm in size. Peduncle up to 12 cm long, shorter than the leaves. Spathe about 8-13 cm long, with an oblong-lanceolate, erect, acuminate limb that is light yellowish-green, sometimes with purple shadings internally, especially in proximity of the margin. Spadix 4-5 cm long, with staminodes and pistillodes. Spadix appendix up to 2.5 cm long, cylindrical or slightly thinner towards its base, brownish-purple in colour. Inflorescence slightly dung-scented. Growing wild in mountains (around 1500 m a.s.l.) of eastern and southern Italy.

 

Arum maculatum

Species with a horizontal rhizomatous tuber that can reach the maximum size of 6 cm long and 2.5 cm in diameter. Petioles 10-50 cm in length. Leaves sagittate-hastate to oblong-lanceolate-hastate, up to 27 × 19 cm in size and often more or less covered with blackish-purple markings that sometimes are bullate too.

Peduncle not exceeding the leaves and often much shorter, up to 25 cm. Spathe up to about 25 cm in length, green outside and greenish-yellowish-white inside, often with blackish-purple spots on the limb. Additional pink or purple flushes may be present on the limb, both internally and externally, and in rare specimens the whole limb is purple. The shape of the limb can range from elliptic-ovate to lanceolate, always with an acute or acuminate tip. Spadix 4-14 cm in length, with pistillodes and staminodes. Spadix appendix long stipitate, more or less clavate, up to 9 cm long, purple to yellow, sometimes brown, often darker on its stipe. This species breaks its dormancy in late winter or in early spring. Europe.

 

Arum megobrebi

Species with a horizontal, unbranched, rhizomatous tuber up to 5 × 2 cm in size. Petioles up to 30-40 cm in length, green to red. Leaves two, hastate-sagittate, about 10-15 cm long and about 5-10 cm wide. Peduncle about 10 cm in length, shorter than petioles, reddish, carrying a foul-smelling inflorescence. Spathe about 12-25 cm long and 8 cm wide, light greenish, whose margins are often purple-reddish. Some rare specimen has the whole spathe tinged purplish. Spadix with staminodes and pistillodes, much shorter than the spathe, up to 10 cm long, with an elongate-cylindrical or slightly clavate, purple appendix. The appendix is never stipitate. This species breaks its dormancy period in late winter. NE Turkey to Georgia. Probably just a form of A. orientale.

 

Arum nigrum

Tuberous species. Petioles 10-25 cm long. Leaves sagittate-hastate, about 10-20 × 8-18 cm in size. Peduncle much shorter than petioles, not exceeding 10 cm, carrying a purple-blackish spathe that can reach 20 cm in length. Spadix with pistillodes and staminodes, reaching the middle of the spathe. Spadix appendix stipitate, cylindrical to clavate, purplish to purplish-beige. The inflorescence emits a horse-dung odour. This species grows wild along the western Balkan coast, in rocky and scrubby habitats.

 

Arum orientale

Horizontally growing discoid tuber that can reach 2.5 cm in thickness and 6 cm in diameter. Petioles 20-45 cm long, often purplish at the base. Leaves hastate, up to about 25 × 15 cm in size. Peduncle about 10-20 cm long, generally shorter than the leaves. Spathe 15-30 cm, ovate or slightly lanceolate. Spathe limb greenish outside, with some purple shading, rather darker inside but often whitish-green in the middle and at the apex. The limb apex bents forwards soon with age. Spadix about 6-15 cm in length, with a cylindrical to slightly clavate appendix. The appendix can be with or without stipe and is 4-12 cm long and some 10 mm in diameter, purple. The stipe is rather long when present. Staminodes and pistillodes are present. The inflorescence of this species smells like horse dung. Eastern Europe, Turkey to Sweden and Balkans to Caucasus. Subsp. longispathum: Spathe caudate, spadix appendix yellow.

 

Arum palaestinum

Tuberous species. Leaves sagittate-hastate, about 20 cm long. The whole plant can reach 50 cm in height. The spathe is dark purple-brown inside and green outside, up to 20 cm in length, bent backwards at maturity. The spadix appendix is slightly spindle-shaped, almost black. This species has a band of staminodes in its inflorescence. It usually has an odour of fermented fruits, but a dung-scented form with different pollinators also exists.

 

Arum pictum

Tuberous species. Leaves ovate-lanceolate, cordate or sagittate at the base, strongly white veined, about 30 cm in length. Spathe 10-25 cm in length, dark red-brown to almost black, dark pink with an ivory-yellowish tip in some populations. Spadix slightly shorter than the spathe, with a black appendix. The whole plant can reach 50 cm in height. It grows wild in open shrubby or rocky habitats in Sardinia, Corsica, Montecristo Island and Balearic Islands and is the only autumn flowering species in the genus.

 

Arum purpureospathum

Tuber discoid and vertical, up to 7 cm in diameter and 3 cm in thickness. Petioles up to 20 cm long, D-shaped in section. Leaves hastate-sagittate, up to 22 × 17 cm, glossy and not very dark in colour. Peduncle around 12-15 cm long, always shorter than the petioles. Spathe up to 30 cm in length, with a lanceolate caudate limb that can reach the size of 23 × 9 cm and varies in colour from dark red to a blackish dark purple. Spadix with staminodes and pistillodes, 6-13 cm long, with a long-stipitate appendix that is cylindrical-clavate in shape and brownish-orange to black-purple in colour. The inflorescence has a slight smell of horse-dung. This species is vulnerable in the wild and only grows in five locations in SW Crete.

 

Arum rupicola

Tuberous species. This is a rather variable species. Leaves up to 25 × 18 cm, hastate-sagittate carried on longer petioles. Inflorescence with a narrow purple-brown spathe and a spadix appendix that can varies from purple to grey-lilac to yellow or brown. The spadix appendix can be rather stout and exceed 30 cm in length. The total height can attain 1 m. It grows wild from Iran to eastern Mediterranean countries. Var. virescens has a purple-edged whitish spathe and a grey-lilac appendix. It has the same distribution than the typical variety but lacking in Jordan, Lesbos and Cyprus.

 

Arum sintenisii

Tuber discoid but irregular, up to 8 cm in diameter and 4 cm in thickness. Leaves hastate. Spathe rather narrow, about 25-30 cm long and 7 cm wide, reddish-brown inside and green outside; sometimes slightly tinged outside too. Spadix dark purple-red, about 20 cm long, clavate. Flowers, staminodes and pistillodes purple. Cyprus and Turkey.

 

Arum × sooi

A stable hybrid between A. cylindraceum and A. maculatum. Leaves slightly hastate, medium green. Spathe limb pink, greenish in the middle. Spadix appendix thinly stipitate, purple-pink, rather short (about 4-5 cm long). Hungary.