ALOCASIA LAUTERBACHIANA
ORIGINAL DESCRIPTION:
First described under the genus Schizocasia in 1890 by Dr. Lauterbach and finally combined under Alocasia lauterbachiana in 1990 by Alistair Hay in his Aroids of Papua New Guinea
Schizocasia Lauterbachiana Engl, n. sp.; foliis petiolo laminae dimidium paullo superante suffultis, superne viridibus, metallice nitidis, subtus atroviolaceis elongato-lanceolato-hastiformibus, lobis posticis brevibus divergentibus lobulo parvo deltoideo obtuso et extimo lineari obtuso instructis, lobo antico elongato lanceolato, utrinque lobis circ. 9 porrectis obtusis instructo.
Foliorum petiolus circ. 2 dm longus, lamina fere 5 dm longa, apicibus loborum posticorum circ. 1.5 dm distantibus; lobi postici sinu amplo sejuncti, lobulo superiore circ. 1.5 cm longo et lato, lobulo extimo circ. 3 cm longo, 1 cm lato; lobus anticus fere 5 dm longus, medio 1.4 dm latus, lobulis obtusis porrectis, nervis lateralibus crassiusculis angulo circ. 40® a costa abeuntibus, nervis secundariis angulo acuto a nervis primariis abeuntibus nervo collective marginali conjunctis. Inflorescentia non adest.
Nova-Guinea: Boassalibach in silva montana montis Sattelberg (Dr. Lauterbach n. 632. — Sterilis 22. Jul. 1890).
Botanische Jahrbücher fur Systematik, Pflanzengeschichte und Pflanzengeographie (Bd. 25:26) (1898)
SYNONYMS: Alocasia wavriniana, Schizocasia lauterbachiana, Xenophya lauterbachiana, Alocasia ‘Purple Sword’
DISTRIBUTION: Northern New Guinea and the Bismarck archipelago
CLIMATE: Tropical humid climate
Humidity is moderate throughout the year, ranging from 60% to 70%
Temperature is varies between the seasons - within the range of 48°F/9°C to 88°F/31°C during the day. Minimum temperatures never dip below 45°F/7°C
Rainy and humid season (October to May) and a dry season between June and October. The average annual rainfall is 1,200 mm
ECOLOGY: In the lowlands in rainforest especially near river edges and forest edge. Masters (I.e.) noted that this species was introduced into Sander's nursery by Micholitz from Celebes. Records to Micholitz's travels are very incomplete and those known (Van Steenis-Kruseman, 1950) do not include Celebes. Alocasia lauterbachiana has never otherwise been reported from there.
SPECIES DESCRIPTION:
Treelet with erect brown stem to 1.5 m tall; leaves c. 6 together in a terminal cluster; petiole to c. 40 cm long, sheathing in the lower l/2-l/3rds, densely mottled with chocolate brown; lamina deep bronze green above, dark purple below, narrowly hastate in outline, with the margin serrately lobed; anterior lobe broadly lanceolate, widest at about midway from the base, to c. 60 cm long, c. 15 cm wide, with up to 9 primary veins on either side of the anterior costa diverging at an angle of about 50 degrees; secondary venation flush abaxially; interprimary collective veins absent; leaves produced after flowering has commenced often much smaller than those before
INFLORESCENCE:
Inflorescences paired, the pair subtended by a cataphyll, second inflorescence of the pair subtended by a small prophyll; peduncle rather short, to 8 cm long, mottled; spathe to c. 14 cm long, constricted about a quarter of the way from the base, the lower part usually triquetrous, greenish ivory boldly vertically streaked with chocolate brown without, greyish and smooth within, the limb narrow, clasping the spadix, opening only level with the male zone, dirty ivory speckled and finely streaked chocolate purple without, dull ivory within; spadix to c. 12 cm long, slender; female zone to 1.4 cm long, c. 1 cm wide at base, with c. 30 pistils; ovaries pale green, close packed, unilocular; stigma button-like, distinctly papillate, faintly lobed; ovules anatropous; interstice of sterile organs equalling the female zone, c. 5 mm diam. at base, tapering to 2.5 mm diam., white, the lower sterile organs turning brown soon after anthesis; male zone c. 3 cm long, 4 mm diam., white; synandria more or less hexagonal, 3 mm long, anthers opening through pores on the tops of the synandria; spadix slightly constricted between male zone and appendix; appendix to c. 5 cm long, 3 mm diam., tapering to a point; berries orange red; seeds unknown.
C,D: The upper structure of the inflorescence consists of a spade covered androecium, with stamens forming a distractile structure. The stamens are extrose, facing away from the center of the Inflorescence. They are numerous and miniscule compared to other flowering plants. This part of the inflorescence extents to 4cm, the longest in its structure, and it’s obscured by the spadix until pollen is released.
F: The ‘male’ structure of the Inflorescence is followed by a short sterile section, measuring 1cm (though in some cases it may be no larger than 1.5 cm)
G: A lack of pollen producing stamens or ovaries at first suggests a useless structure. However, the purpose of this short section is to prevent self-pollination, by separating contact between the ‘male’ and ‘female’ areas. Nonetheless, whenever the spade blade is uncovered, this section remains partially obscured, as a buffer between both sexually active areas.
H: On the lowest section of the Inflorescence, enclosed in the spade, the floral chamber can be observed This section, only partially opens during the reproduction process, The flies are attracted by the odor of female-phase inflorescence in the early morning on the first day of anthesis. They feed, mate and oviposit in the inflorescences for 1 day. On the second day, the flies, covered with pollen grains, leave the male-phase inflorescences for the next female-phase inflorescences (Pollination mutualism between Alocasia macrorrhizos (Araceae) and two taxonomically undescribed Colocasiomyia species (Diptera: Drosophilidae) in Sabah, Borneo).
I, J: The present unpollinated ovaries are a bright green, followed by a bright orange color as the berries mature (possibly due to bird dispersal), ovaries are superimposed, in grid floral structure, each with a stigma in the outermost area of the ovaries.
K: A cross-section of the ovaries, demonstrating a clear view of the ovule can be observed. The overall structure of the inflorescence demonstrates the method of pollinator trapping, a deceptive manner of pollination often observed in members of the Araceae family with unisexual flowers.
VARIEGATED FORMS: GREEN ON GREEN; WHITE (SECTORAL); YELLOW (SECTORAL); YELLOW (MOTTLED)
ETYMOLOGY: The plant is named after German-Polish explorer and botanist Dr. Karl Adolf Georg Lauterbach
Its previous synonym, A. wavriniana was named in compliment to the Count of Wavrin (Comte de Wavrin, member of the noble Wavrin family of Flanders)
NOTES: The lectotype specimen of A. wavriniana was evidently prepared from the clone introduced to the Sanderian nursery by Micholitz.
This species seems to be identical in its inflorescence to A. brancifolia, with the possible exception that the stigmas are button-like and distinctly papillate in A. lauterbachiana, and lobed and indistinctly papillate in A. brancifolia (it is not clear that these character states are constant). Nevertheless, it is highly distinctive and shows no sign of intergrading with anything else.
It is not known to set seed. That the berries are orange red is known from a parthenocarpic example in cultivation. Peekel (1984) noted that in New Ireland (island in Papua New Guinea) it is grown as an ornamental by the indigenous people, and that it does not set seed there.
The plants that A.H. observed in cultivation in various parts of the world, and the herbarium material, are astonishingly uniform, suggesting that a clone may be involved.
Marchant (1971) notes that there are 70 chromosomes, whereas the usual diploid number in Alocasia is 28, suggesting that this plant is a pentaploid. The plants freely propagate themselves vegetatively. However, at least two collections from the Bismarck Archipelago seem to be from wild plants growing in the forest floor.
Other specimens seen:
PAPUA NEW GUINEA. Cultivated at Bulolo, ex Dreikikir, East Sepik Prov., Hay 1401 (LAE); Alimbit R., Kandrian, West New Britain, NGF 22486 (LAE); 8 mi up Danfu River, nr Manga, Namatanai, New Ireland, NGF 46034 (L, LAE); cult. Lae Botanic Garden, Nicolson 1395 (K, L, LAE); New Ireland, Peekel 56 (BO, L).
CULTIVARS: N/A
HYBRIDS: N/A
