ALOCASIA REGINAE

Species

ORIGINAL DESCRIPTION:

The Gardeners' chronicle: a weekly illustrated journal of horticulture and allied subjects 21: 711 (1884)

L'Illustration horticole : journal spécial des serres et des jardins, ou choix raisonné des plantes les plus intérressantes sous le rapport ornemental, comprenant leur histoire complete, leur description comparée, leur figure et leur culture v32:P11 (1885)

SYNONYMS: Alocasia regina (invalidly published, not accepted)

DISTRIBUTION: Malaysia (Sarawak): endemic to the limestone karst of the Gunung Mulu area.⁵,⁶,⁷

CLIMATE: Equatorial rainforest climate with no marked dry season.⁸

Rainfall at Gunung Mulu National Park averages between 4,000 and 5,000 mm a year, highest in April–May and October–November and lowest in August–September.⁸

Temperature in the Melinau lowlands, where the species grows, ranges from about 23 °C to 26 °C (73–79 °F).⁸

ECOLOGY: On the floor of primary lowland rain forest: Jermy 13579 on alluvial soil with residual limestone karst; ca. 40-270 m altitude.² Restricted to limestone, often in swampy forest.⁶

SPECIES DESCRIPTION:

Small herb 20-30 cm tall; rhizome ca. 1.5 cm diam.; leaves 2-4 together; petiole 10-25 cm long, sheathing in the lower 1/4-1/3, sparsely to densely minutely pubescent, green to densely spotted purple; blade broadly ovatosagittate to ovato-sagittate, 13-25 cm long, thickly leathery, dark green, paler abaxially or flushed purple throughout; margin entire to shghtly and irregularly sinuate; anterior lobe widest ca. 1/3 of the way from the base, the apex acute to obtuse and then apiculate; anterior costa with 3-4 abaxially pubescent primary lateral veins on each side diverging at 60° (proximal)-45° (distal) and with small axillary glands; secondary venation adaxially impressed, abaxially flush with the lamina to somewhat impressed (dry), conspicuous and apparently broad (ca. 1 mm) owing to pigment in the bordering lamina, forming mor-or-less well-defined interprimary collective veins at least in the outer part of the blade; posterior lobes 1/3-2/5 the length of the anterior, the inner sides very narrowly oblanceolate; posterior costae naked in the sinus for 4 mm to 1 cm, basally diverging at ca. 90-100° then somewhat to abruptly back-turned

INFLORESCENCE:

Inflorescence pairs solitary; peduncles ca. 1/3 the length of the petiole at anthesis (not or hardly elongating in fruit), subtended almost throughout their length by very narrowly lanceolate cataphylls; spathe ca. 5-7 cm long, constricted ca. 1.5-2 cm from the base; lower spathe ovoid, white, sometimes spotted purple; limb narrowly ovate, white and spotted to suffused purple; spadix distinctly shorter than to subequalling the spathe, sessile, ca. 5 cm long; female zone 1 cm long; pistils flask-shaped; style short, ca. 0.5 mm; stigma 2-3-lobed; interstice 3-5 mm long, partly naked to covered with synandrodia; male zone subcylindric, 9-15 mm long ca. 1/4-3/4 held within the lower spathe chamber; synandria rhombohexagonal, ca. 1.5 mm diam.; thecae not overtopped by synconnective; appendix 1-2 cm long tapering to somewhat obtuse, ca. 3 mm diam (dry); fruiting spathe ovoid, ca. 2.5 cm long.

VARIEGATED FORMS: WHITE, YELLOW, YELLOW MOTTLED

ETYMOLOGY: The specific epithet reginae, from the latin regina meaning queen, was given to this Alocasia as it was first introduced to the Emperor and Empress of Russia at the International Exposition of St. Petersburg in 1884 by the ‘Compagnie Continentale d'Horticulture’

NOTES:

This species is evidently closely allied to the variable Alocasia scabriuscula, differing in the smaller size overall, inflorescences in single pairs, relatively much longer peduncle and the long, narrow inflorescence cataphylls.
The description is pieced together from four incomplete collections. The type differs from the only other flowering specimen, Jermy 13579, in having a larger proportion of the male zone exserted from the lower spathe and in having the interstice covered with synandrodia.
Hotta (1967: 156) cited several specimens from Brunei and Sarawak as this species. I (A. Hay) have not seen any of the collections concerned, but it would appear from his notes (loc. cit.), in which he gives significantly larger dimensions, that these specimens are probably of A. scabriuscula.
Hay lists Hotta’s plants under A. scabriuscula as “?Alocasia reginae sensu auct.”,² and no later source records A. reginae from Brunei, so Brunei is not part of its range on this page.
Alocasia reginae has been in cultivation in the U.S.A. for many years, under the cultivar name Alocasia reginae 'Elaine' and the cultivar is also illustrated in Burnett (1984: 77, fig. 4)
Other specimens seen: SARAWAK: Limbang Distr., Sg. Terikan, Chew 1183 (GH, K, L, SING); G. Mulu National Park, around Sg. Berar Camp, Jermy 13579 (K). KALIMANTAN: Headwaters of Sg. Kahayan, 5 km NE of Haruwu Village, Burley et al. 527 (GH).
Asih & Lestari (2022) report that Burley et al. 527 is misidentified and, citing Peter Boyce (pers. comm., 13 November 2021), that A. reginae is restricted to the karst area of Mulu National Park.⁵ That specimen was the only record from Kalimantan, so this page no longer lists Indonesia. Hay’s 1998 range, “three localities in Sarawak and Central Kalimantan”, counted it.²
Plants from the Baram and upper Rejang river systems sold as forms of A. reginae are treated in the Field note below as Alocasia aff. reginae.⁹,¹⁰

STORY:

STORY TITLE: Alocasia aff. reginae: the Baram plants

In August 2021 the Sarawak grower CK Lim wrote two Facebook posts about plants sold as A. reginae. In the first he grew plants from five sources side by side, from Mulu (the clone ‘Elaine’), Limbang, Middle Baram, Upper Baram and the Bakun–Asap area, and singled out the Middle Baram plant as very different from the rest; botanist friends had told him it might be a new species.⁹ The photographs here are his.

The second post is about that plant.¹⁰ Online sellers in Miri had offered it from about April 2021 as ‘Dark Reginae’, ‘Reginae Miri’, ‘Reginae Princess’ and ‘Reginae Natif’. Its leaves are glossy dark green, flushed purplish maroon beneath, mostly sagittate and diamond-shaped but a few nearly round, and its spathe limb is wine-red outside and pinkish inside. The limb of A. reginae itself is white, spotted to suffused with purple.² CK Lim wrote that he suspected it was a new species, and Peter Boyce answered under the post in one word: “undescribed.”¹⁰

Where it grows. An expedition to Long Urun, Ulu Belaga (Kapit Division), posted in situ photographs of the plant dated 23 January 2021, which put one population between Long Urun and Mount Dulit. CK Lim’s own plants were later traced to the middle Baram (Miri Division). On his map the three places lie within about 50 km of each other, Mount Dulit roughly 40 km from Middle Baram and 38 km from Long Urun, and all well south of the Mulu and Limbang records of A. reginae.¹⁰

Why these places are not on the map. They come from sellers and an expedition’s photographs, not from herbarium specimens, and the plant they describe is probably not A. reginae at all. The map, the Distribution line and the climate on this page show only the published range of A. reginae. Middle Baram, Mount Dulit and Long Urun stay off it until the plant is collected, identified and published.

What “aff.” means. It is short for the Latin affinis, “related to”. Alocasia aff. reginae marks a plant that resembles A. reginae and is probably its close relative, but differs from it in ways that suggest a separate species: here the leaf colour, the wine-red spathe limb and a range in other river systems. It is a working label, not a name; the plant becomes a species only when someone describes it from a specimen. Close relatives replacing one another on separate ranges is a familiar pattern in Bornean Alocasia: A. reginula takes the place of A. reginae on the limestone of Bukit Tabin in eastern Sabah.⁶

CULTIVARS: Alocasia reginae 'Elaine', Alocasia reginae ‘Miri’

HYBRIDS: