Etymology. Latin,
longus = long and
flos = flower.
Named by Wallich for the long
flower.
Notes. The cultivated material
(M11P48) was grown from dormant rhizome divisions
of Kress GH2003-051 cultivated at the Smithsonian Institution, and originally
collected on 18 June 2003, in Rakhine state, Burma as Kress 03-7305 (US). This
accession compared very well with Wallich’s description and watercolour (Fig. 1). The
only exception was the lack of pigmentation on the lower lamina surface, a character
found to be highly variable throughout this clade. Of note are the very small, bulb-
like rhizomes which develop en masse, underground, at the base of the pseudostem.
Each of these small entities are loosely attached to the main rhizome and if separated
can produce a new plant. Wallich 6989B
(CAL, K, microfiche 7394) annotated and
listed as
G. longiflora (Wallich 1832) has a terminal inflorescence and as such, appears
to be a different taxon, perhaps related to B. siphonantha (King ex Baker) M.Sabu,
Prasanthk. & Škorničk.
Boesenbergia kerrii Mood, L.M.Prince & Triboun,
sp. nov.
Boesenbergiae longiflorae (Wall.) Kuntze affinis, inflorescentiis 4 vel plus floribus,
floribus maioribus 3.8-4.0 cm longis c. 2.8 mm latis, labello elongatiore truncato
apice indentato differt.
TYPUS: Mood & Triboun 12P170, Cultivated in Hawaii, USA, 1 Nov 2012 (holo BK;
iso AAU). Originally from Thailand, Tak Province, Khao Pa Wo District, near Mae
Sot, c. 600 m asl, 16º48.783'N 98º39.70'E, 8 September 2010, Mood & Triboun 2044,
cultivated as M2044. (Fig. 8, 9, 17 & 19B)
Deciduous herb up to 1.2 m tall; rhizome small, globular, c. 1 cm diam., externally red,
pink or light tan, internally light yellow to white; multiple, small bulb-like rhizomes
surrounding the main rhizome, c. 1 cm long, pink turning red with age; tuberous roots
few to numerous, c. 12
× 0.5-0.8 cm, tapering to a point, externally and internally
white, root hairs few, c. 10 mm long, thin, white. Pseudostem up to 30 cm, composed of
leaf sheaths, base oval, c. 2
-2.5 cm diam., 1-
2 leafless sheaths at the base, leaf sheaths
longitudinally ridged, green, glabrous, margin hyaline. Leaves 5
-8 per pseudostem;
petiole 9
-18 cm, deeply channelled, green, glabrous; ligule slightly bilobed, lobes
an extension of the hyaline margin, 2 mm long, green, glabrous; lamina elliptical or
broadly ovate, c. 41
-61 × 20-21 cm, plicate, ventrally dark green, glabrous, dorsally
lighter green, glabrous with a few hairs on the midrib, base rounded to cordate,
sometimes asymmetric, apex acute to long acuminate.
Inflorescence radical, c. 3-6
or more per pseudostem, up to c. 15 cm long (including peduncle) produced from the
side of the rhizome; peduncle c. 1
-4 cm long, white, glabrous, basal sheaths 1-2 , pink
and white, pubescent; spike horn-shaped, 5
-12 × 1-2 cm. Bracts cymbiform, 4-6, c.
4
-5 × 1.5-2 cm, distichously arranged, green and red, glabrous, each bract enclosing
one flower, some basal bracts sterile, apex sometimes curved;
bracteole cylindrical,
c. 5
× 0.5 cm, white, translucent, glabrous, open to the base, apex acute.
Flowers 3-6
64
Gard. Bull. Singapore 65(1) 2013
per inflorescence, up to c. 15 cm long.
Calyx tubular, 2.0 × 0.5 cm, white, translucent,
glabrous, apex bi-dentate. Floral tube 12
-14 cm long, c. 3 mm wide at the base, white,
glabrous; corolla lobes (dorsal and ventral) linear to lanceolate, c. 2
× 0.5 cm, white
to light yellow, glabrous, margins involute; androecial tube cup-shaped, c. 4
-5 mm
long, c. 10 mm diam. at the top, yellow, glabrous externally and internally. Labellum
saccate, semi-orbicular, 3.8
-
4 cm long, 2.2 cm wide (when flattened at the broadest
point) light yellow, throat centre orange-red, maculate with yellow showing through
as dots, red pattern broadening toward the lip apex, ending c. 10 mm short of the
apex, then dark red streaks to the apex, glabrous, margin entire, revolute on the sides,
apex shortly to deeply bilobed, 2
-8 mm, slightly wavy; lateral staminodes obovate,
1.3
× 1 cm, light yellow, glabrous, apex rounded, revolute, margin wavy.
Stamen 11
mm long, filament 2 mm long, 2 mm wide at the base, light yellow, with a few short
glandular hairs, anther 9 mm long, 3 mm wide (first day) then 6 mm wide (thecae
diverging on the second day) apex rounded with no anther crest, thecae c. 9
× 1 mm,
light yellow, dehiscing along the entire length. Ovary c. 8
× 4 mm, trilocular, axile
placentation, white, glabrous; style
filiform, yellowish-white, glabrous, stigma round
to oval, white, ostiole oval, without cilia, exuding a sticky liquid on the second day;
epigynous glands linear, two, 5 mm long, light yellow.
Fruit not seen. (Measurements
based on living, cultivated material of M2044).
Distribution. This species is prevalent in western Thailand from the southern area of
Tak Province to the southern area of Kanchanaburi Province. It should be expected in
E. Burma.
Ecology. This species has been found only in close proximity to limestone rock outcrops.
In almost all situations observed, the primary canopy component was bamboo with
mixed deciduous, hardwood species. The plants grow in the cracks between limestone
rocks where there is accumulation of organic matter or in deeper soils surrounding
the limestone karsts. In the dry season these areas are often burnt, leaving a biochar
residue. Shade is variable from light to medium. Plants commonly occur as single
individuals, but over time, can create small populations of scattered plants. The result
is a group of separate stems growing close together or scattered about.
Phenology.
Flowering from June to October with a two-day flowering cycle for each
flower.
Etymology. Named in honour of Arthur F.G. Kerr (1877
-1942) one of the ‘founding
fathers’ of botany in Thailand. His two specimens from the Thailand/Burma border
(1922) appear to be the first collections of this new taxon.
Additional specimens examined: THAILAND.
Tak Province. Umphang, Kao Hua limestone
hills, 13 Jun 1922, Kerr 6133 (P, C; *); South of Mae Sot along Maenam Moei, 17 Jun 1922,
Kerr 6144 (K, L, P; *);
Khao Pha Wo, 23 Jul 1973,
Murata, Fukuoka & Phengkhlai T-16947
(BKF); Khao Pha Wo, 23 Jul 1973, Murata, Fukuoka & Phengkhlai T-16949 (BKF, KYO,
67
Boesenbergia longiflora and related taxa