For
almost fifty years only one endemic Fritillaria
was recognized from Japan. In April 1912, Toshitaro Akaki collected a
narrow-campanulate flowered specimen in Bitchu Province in the
foothills of the
Chūgoku Mountains, Southern Honshu. The following month Akaki collected
two
further specimens which were subsequently described as a new species.
The young
Genichi Koidzumi, who had studied under Jinzo Matsumura at the Imperial
University, Tokyo, described and illustrated Akaki’s
specimens as F. amabilis or
hosabana-kobaimo
(slim-flowered little fritillary).
F. amabilis
also
differs from the broadly-campanulate F.
japonica in its small basal nectary and style which is only
divided slightly
at its apex. In
Flora
Bitchuensis (1929) the
amateur botanist Zensuke Yoshino published a report
by Kanjio Maehara of a second location in Kumamoto Prefecture, Kyushu,
revealing its much wider distribution. Further narrow-campanulate Fritillaria were
subsequently recorded
through-out most of Southern Honshu, Kyushu and Shikoku.
In
1964 Dr. Shozo Noda of Osaka Gakuin
University published a new chromosome complement for Fritillaria
after discovering 11 and not 12 chromosomes in two
populations of F. amabilis in
Northern Kyushu. Noda with Naohiro Naruhashi subsequently divided the
narrow-campanulate flowered Fritillaria
into two species. Those from Central Kyushu and Shikoku had the usual
12
chromosomes and blue, not white, anthers so these were named F. shikokiana. Dr. Noda also revealed
the presence of achiasmate meiosis in F. amabilis. This form
of meiosis had never previously
been observed in any plant.
Aid to
identification
Within
the Fritillaria Japonica
Group, F. amabilis is the
most variable, even
within individual populations. This
variation is mostly in leaf colour, markings, and size but also in
height and
tepal marking. However, within the group only F. amabilis and F.
shikokiana
have narrow-campanulate flowers, the outcome of their basal nectaries.
These
two species can be divided by their anther colour, white in F. amabilis and blue
in F.
shikokiana.
Geography and disribution
Of
the eight Japanese endemic Fritillaria
only the two narrow-campanulate flowered species are
distributions across more than one island. F.
amabilis
has a large distribution in Southern Honshu and Northern Kyushu and
across a
wide altitudinal range. In Honshu the species is found at lower
altitudes on
the south side of the Chūgoku Mountains in pockets that remain
undeveloped for
forestry and agriculture. In Kyushu F.
amabilis is found
at the tops of mountains where the lower reaches have
been fully developed. Two populations have survived only because of
their
proximity to small shrines which prevented these sites from being
developed.
Cultivation
Although Fritillaria
amabilis is rare in
cultivation it is not difficult to grow. Use equal
parts of composted bark, leaf mould and fine grit in terracotta pots.
Plunge in
an open frame away from direct sunlight. The bulbs must be kept moist
at all
times. As F. amabilis flowers in
late winter hand pollinate to encourage
seed set. Seeds should be harvesting as soon as the capsule opens and
sown
directly.
Description
Fritillaria amabilis Koidz. in Matsumura’s Icones Plantarum
Koisikavensis 1914: 21.
Bulb 10-15 mm in diameter, white
twin scaled covered in a thin translucent tunic. Stem 9-25 cm, slender, smooth
topped by a whorl of 3 leaves with 2 opposite leaves 1-20 mm below. Leaves
green or red, often mottled with white or occasionally with a white
longitudinal central strip, all narrow lanceolate or linear, opposite pair
20-70(-95) x (1.4-)3-18 mm, whorled leaves 17-60(-75) x (0.7-)1-8(-11) mm.
Pedicel 4-13 mm long, emerging from the middle of the whorl of leaves, green,
grey or dark pink, often wrinkled. Flowers nodding narrow-campanulate, white
with pink or purple-brown longitudinal veining. Tepals entire 15-20(-26) mm long,
inner 3.5-7 mm, outer 3-6mm wide, apex obtuse or pointed often recuved.
Nectaries at the base of the tepal, a green dot with pale yellow streak towards
the apex, 6-11 mm long. Filament thin, papillose, up to 8 mm long. Anthers
narrow oblong to 6 mm long, white. Style papillose, white, to 7 mm long, apex
divided 1 mm. Capsule green, pendulous, pyramidal with a concave base, 7-23 mm
long, 7-14 mm wide. Seed ovoid, not winged with an elaiosome. 2n = 22.
Japanese Name: ホソバナコバイモ (Hosabana-kobaimo)
Habitat: below deciduous
tree, with Anemone, Corydalis, Chrysosplenium. 100-1000 m
Flowering period: Late
February to early April.
Type: Japan, Honshu, Bitchu
(West Okayama), Atetsu-gun, Kusama-mura, May 1912, T. Akaki 7 (holotype TI!).
Conservation Status: Japanese Red
Data Book 2007, Near Threatened (NT)
