ARUM HAINESII

PROTOLOGUE: Arum hainesii , published in Kew Bulletin 36: 643 (1981).

Arum hainesii H. Riedl sp. nov. ex affinitate Arum conophalloidis Kotschy ex Schott, a quo differt zona superiore florum sterilium quam ea inter flores femineos et masculos et quam pars mascula inflorescentiae distincte longiore, parte mascula inflorescentiae brevi longitudine diametrum haud attingente, parte sterili spadicis (clava) cylindrica, manifeste longiuscule stipitata stipitem diametro aequante et ab eo colore imprimis diversa vel eo crassiore. Typus: Iraq, Baquba, shady date and orange garden, 9 May 1961, A. D. Q. Agnew & E. Hadač 3581 (holotypus K).

DISTRIBUTION: E. Iraq: Iraq.

SPECIES DESCRIPTION:

Tuberous herb sprouting (in autumn?) from a discoid, vertically orientated tuber 3–6 cm across, 2–2.5 cm thick. Petiole terete, 45–60 cm long, 4–5 mm wide, mid-green, paler basally. Leaf-blade hastate, apex acute to slightly obtuse, 10–33 cm long, 8.5–24 cm wide, dull mid-green.

INFLORESCENCE:

Inflorescence scent unknown. Peduncle much shorter than the leaves, terete, 8–10 cm long, 3–4 mm wide, mid-green. Spathe 15.5–25 cm long; spathe-tube cylindric, 3.5–4 cm long, 2–2.5 cm wide, constricted apically, exterior pale green, interior paler, usually suffused with purple; spathe-limb lanceolate, 12–21 cm long, 2.5–4.5 cm wide, erect, acuminate, externally and internally pale green. Spadix less than ½ as long as the spathe-limb, up to 13 cm in total length; appendix cylindric, stipitate, 4.5–5.5 cm long, 4–4.5 mm wide, pale brown, slightly farinose (artifact of drying?). Staminodes in 5 whorls forming a zone 4–5 mm long; bristles filiform, flexuous, 7–8 mm long, pale cream; bases bulbiform, smooth, dull cream. Interstices: upper 2.5 mm long, ± smooth, cream; lower 2 mm long, longitudinally ridged, cream. Staminate flowers in an oblong zone 2 mm long, 5 mm wide; anthers and connectives dark purple. Pistillodes in 3 or 4 whorls forming a zone 2.5–3 mm long; bristles filiform, flexuous, 4–5 mm long, pale cream; bases compressed-semiglobose, smooth, cream. Pistillate flowers in a cylindric cluster 8–10 mm long, 3–4 mm wide; ovaries oblong, truncate, 2–2.25 mm long, pale yellow, purple apically; stigma cream. Fruiting spike oblong-cylindric, c. 4 cm long, 1.5 cm wide; berries ovoid, 4.5–9 mm long, 3–3.5 mm wide.

ECOLOGY:

To date known only from cultivated ground; altitude: 40 m

DISTRIBUTION MAPS:

ETYMOLOGY:

For Haines, who made the 1961 collection at Ba'quba, eastern Iraq, on which Riedl based the species.

REFERENCES:

1. Plants of the World Online, Royal Botanic Gardens, Kew — Arum hainesii

2. Kew Bulletin 36: 643 (1981) — protologue.

3. Boyce, P.C. 1993. The Genus Arum: a Kew Magazine Monograph. Royal Botanic Gardens, Kew.

4. Boyce, P.C. 2006. Arum – a decade of change. Aroideana 29: 132–137.

5. Chartier et al. 2013. Geographical variations of odour and pollinators, and test for local adaptation by reciprocal transplant of two European Arum species. Functional Ecology.

6. Diaz et al. 2006. The effectiveness of some mechanisms of reproductive isolation in Arum maculatum and A. italicum (Araceae). Botanical Journal of the Linnean Society.

7. Albre et al. 2003. Pollination ecology of Arum italicum (Araceae). Botanical Journal of the Linnean Society.

8. 2006. Studies on the Genus Arum (Araceae).

9. Gibernau et al 2003. Arum Pollen longevity & viability.