Written by Maggie
Mar 02 2021
Stylidium uliginosum, a small annual hers, 5-13 cm tall. Leaves are all basal, ovoid, ovate to obovate, 5-8 mm long, apical obtuse or rounded, entire glabrous; Corolla is white, ca. 2 mm long, capsule thin columnar, ca. 8 mm long.
Stylidium uliginosum is a small annual herb, 5-13 cm tall. Leaves are all basal, with very short stalks, ovoid, ovate to obovate, 5 -- 8 mm long, apical obtuse or rounded, entire, glabrous, veins inconspicuous. Stylidium uliginosum has 1-3 stems, no leaves, unbranched, or bifurcated branches, sparse short glandular hairs on the upper part. Inflorescences are long, sparsely spiked. Flowers are small, sessile; Bracts are ovate, less than 1 mm long; Calyx tube of Stylidium uliginosum is (ovary) narrow, sparsely glandular-hairy, lobes small, anteriorly 2 united into a shallow-2-lobed lobe at the apex, 1.8 mm long, the remaining 3 lobed, 1.2 mm long; Corolla is white, ca. 2 mm long, tube short, anteriorly one lobe very small, ovate, reflexed into a labial piece, the remaining 4 spreading backward, the last 2 longer, 2 lobed at the top, with appendage at the base; The pistil column of Stylidium uliginosum is 3.5 mm long, protruding; Ovary is 2-loculed. Capsule fine columnar, ca. 8 mm long.
Stylidium uliginosum was born in the hills and streams in the wet grass.
Stylidium uliginosum distributes in Guangdong coastal area. Sri Lanka and the northeastern state of Queensland in Australia also have them. The type specimens were collected from Sri Lanka.
There are about 300 species in the genus Stylidium uliginosum, mainly distributed in south-west Australia, with a small number in tropical Asia and southern China. There are only two species in China, Stylidium uliginosum(Stylidium uliginosum) and Stylidium uliginosum(Stylidium tenellum).
Stylidium uliginosum is mostly perennial, with a few annual or subshrub plants ranging in height from a few centimeters to 1.8 meters. Leaves are simple, opposite, alternate, or clustered on stems, or basal and arranged in a rosette, without stipules or stipules reduced to scales; Flowers of Stylidium uliginosum are bisexual, solitary, or zygomorphic, rarely actinomorphic, consisting of racemes, cymes, or sparsely spicate; Calyx tube is adnate to ovary, 5-7 lobed, somewhat diciliate; Corolla of Stylidium uliginosum is convalescent, lobes imbricate, unequal, lowest-lobe labellate; Stylidium uliginosum has 2 stamens, combined with the style into a column, known as the stamen column, the top of the first downward curved, touch elastic, anthers 2 locules;Ovary inferior, 2-loculed or 1-loculed at the base, with multiple ovules in each locule; Capsule, seed numerous, with fleshy endosperm.
Stylidium uliginosum is also known as triggerplants because it protrudes from the center of a Flower and bends downward in an inverted U shape. When insects come to gather nectar, it is mechanically stimulated and pops out within 10 to 20 milliseconds. After a few minutes to half an hour to return to the initial position (the speed of motion depends on the temperature, the higher the temperature, the faster the speed). The movement of the synchylum column is caused by a motor tissue located in the curved part of the synchylum column. The shape of this motor tissue changes after stimulation. Close column in the process of close columnpillar trigger stigma will contact with insects because the stamens and stigma mature time is different, so to avoid pollinate the flowers, stamens mature first, a close column with stigma pollen during the contact with the insects to insects, after mature stigma, during the next close columnpillar trigger stigma will accept to insects to bring pollen.
Stylidium uliginosum has short glandular hairs similar to sundew in flower stems, calyx and dorsal sides of petals. The glandular hairs have red glands at the top of the glandular hairs, which secrete mucus and digestive juice. Stylidium uliginosum can catch insects, but they are weak in catching insects.