AMORPHOPHALLUS LONGICONNECTIVUS
PROTOLOGUE: Amorphophallus longiconnectivus Bogner, published in Kew Bull. 50: 397 (1995).
Amorphophallus longiconnectivus Bogner, sp. nov. Sect. Rhaphiophallo affinis interstitio nudo zonam femineam mascula discedenti sed organis neutris deficiens, Pseudodracontio affinis supra zonam masculam interstitio nudo appendicem staminodiis irregularibus praeditam ferenti, Amorphophallo margaritifer affinis staminis connectivo prominenti conoideo, aliis speciebus omnino divergens regione apicali zonae masculae sterili filamentis plerumque thecas deficientibus tecta. — Typus: India, Central Provinces, Piparia, June 1910, H. Haines 3590 (holotypus K!).
SYNONYMS:
HETEROTYPIC SYNONYMS: Plesmonium burkillii Engl. & K.Krause ex Haines in Bot. Bihar Orissa 5: 861 (1924), not accepted by the author.
DISTRIBUTION: India (Madhya Pradesh, Maharashtra): India.
DISTRIBUTION NOTE: India: Madhya Pradesh, Piparia — the only known locality, where the species was rediscovered in 1997 for the first time since Haines's original 1910 gathering⁵.
SPECIES DESCRIPTION:
Tubers subglobose or depressed globose, 4.5-7.0 cm diam. and 2-5 cm thick in vegetative phase, 6.5-8.0 cm diam. and 4-6 cm thick in reproductive phase; roots numerous, 1-2 mm diam.; offsets small, globose or fusiform, 6-12 in number per tuber, each 8-10 mm diam. and 1.2-1.8 cm long. Petiole 35-77 cm long, 1.2-2.3 cm in diam. at base, smooth, light green with dark brownish, narrow-elongated stripes, paler towards the upper portion; leaflets sessile, linear-lanceolate, 14.0-7.5 cm long and 2-4 cm broad, acuminate at apex, base unequal and decurrent on rachis, pale green below; margin slightly undulate.⁵
INFLORESCENCE:
Peduncle smooth, 62-110 cm long, 1.2-1.7 cm diam. at base, identical with petiole in colour and patterning. Spathe broadly ovate to broadly triangular, usually broader than long, 10-14 cm long, tip acute, completely convolute, not differentiated into basal tube and upper limb, pale green outside, pale purplish within with a dark purplish verrucose base. Spadix as long as or slightly shorter than the spathe, with a pale green stipe c. 1 cm long and c. 1.2 cm diam.; female zone 1.3-2.5 cm long and 1.2-1.4 cm diam.; staminodial zone 8-9 mm long and 1.2-1.4 cm diam.; male zone 3.2-4.0 cm long and 0.8-1.3 cm diam.; upper sterile zone 1.5-3.0 cm long, clothed with sterile flowers and rarely with a few scattered fertile stamens; without or (usually) with a stipitate appendix. Female flowers: ovary subglobose, c. 2 mm high, c. 2.5 mm diam., greenish, 2-3-locular; style very short, c. 1 mm long; stigma 2-3-lobed, 1-2 mm diam., papillate. Staminodial zone with loosely arranged thick-based echinate fleshy sterile flowers, each 3-5 mm long, c. 1 mm broad at base, rarely a few with forked tips. Male flowers: golden-yellow, each 2-3 mm long, 1-2 mm broad, filaments short, flat, thecae lateral, ellipsoid, 1.5-2.5 mm long; connective elongated to 1.0-1.5 mm above the level of the thecae tips. Sterile flowers more or less subulate, cream. Spadix appendix stipitate, stipe 3-8 mm long, 2.5-4.0 mm diam., green, terminal part 7-8 mm long, c. 3 mm diam., bearing irregularly formed cream-coloured rudimentary male or female flowers or irregular protuberances. Rarely plants without neuter flowers and lacking a spadix appendix are observed. Fruits ellipsoid, 8-10 mm long, 6-8 mm diam. Seeds 2-3, ellipsoid, 6-8 mm long and 4-6 mm diam.⁵
PROPAGATION:
Rooting percentages ranged from 0% with early October cuttings to 46.7% for early September cuttings.
ETYMOLOGY:
Named for the prominently elongated connective of the stamens, which projects 1.0-1.5 mm above the tips of the thecae — the character Bogner singled out as remarkable when he described the species from a single 1910 herbarium sheet.²
NOTES:
1. Amorphophallus longiconnectivus was described from a single specimen collected in 1910 in central India and deposited at Kew, lacking both leaf and tuber. It was rediscovered at its type locality in Madhya Pradesh in 1997, for the first time since Haines's original gathering, and the living plants allowed the species to be described in full.⁵
2. The species is very distinct and probably represents a new monotypic section of the genus. Its naked sterile axial region recalls sect. Rhaphiophallus (though the characteristic sterile flowers of that section are absent), its appendix of irregular staminodes on a naked stipe recalls Pseudodracontium, and the mostly sterile, filament-clothed apical region of the male zone is unique in the genus. The prominent connective is shared with Amorphophallus margaritifer and with Typhonium, Theriophonum and Biarum, and the stamen morphology is probably primitive in the genus.²
3. The spadix is highly variable: usually it carries a stipe, a female zone, a staminodial zone, a male zone, an upper sterile flower zone and a stipitate appendix, but in some plants the appendix is completely lacking, and very rarely both the staminodial zone and the appendix are absent.⁵
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus longiconnectivus Bogner
2. Kew Bull. 50: 397 (1995) — protologue.
3. Alan Galloway — Amorphophallus longiconnectivus, alangallowaybotanicals.com.
4. Propagation of Amorphophallus by Leaf Petiole Cuttings — Juniper Level Botanic Garden
Additional photos by Jeremiah Baer