Lobelia dortmanna

Common name: Water Lobelia
Scientific name: Lobelia dortmanna
Genus: Lobelia 半邊蓮屬
Family: Campanulacee 桔梗科, bellflower family

Remarks:

Origin: native

Date: 30th July (1st location) & 13rd Aug (2nd and 3rd locations)

[606] Found near the shore of a lake. You could see a lot of flower stalks emerged from the water. (in the first location)

[543] Also found near the shore of  a lake of a higher altitude. (in the 2nd location)

[415] Emerging flower stalks in the middle of the above photo. (in the 2nd location)

[344] (in the 2nd location) Water lobelia are in the middle of the above photo. Those plants  that are partly floating on the lake are Sparganium angustifolium 線葉黑三棱, floating bur-reed. 

[093] A lot of emerging flower stalks! (in the first location)

[087] (in the first location)

[553]  The water is so clear that you could see the basal rosette of the plants. (in the 2nd location)

[200] It seems they like shallow water. (in the 3rd location)

[019]  The basal rosette of the plants. (in the 2nd location)

[180] Water lobelia (left one with shorter and brighter leaves) and Isoetes lacustris, quillwort (right one with longer and thinner leaves) are found living together side by side. (in the 3rd location)

[168] Not all plants have the flower stalks. (in the 3rd location)

[186] (in the 3rd location) It is so dry this year that in some part of this lake the shore is exposed and you could gladly examine the plant without need to get into the water. (but is would be stressful to the survival of the plants....)

[187] (in the 3rd location) Basal rosette with 2-4 cm, linear and entire leaves. Try to see the underside of the leaves.

[038]  (in the 2nd location) A lot of water lobelia were found uprooted and were floating on the lake. What kinds of animals would do this? Birds?

[058]  (in the 2nd location) Take one plant out of  water and examine it. 

[049]  (in the 2nd location) The leaves are quite thick in texture.

[052] (in the 2nd location) Fibrous roots could also be seen now.

[054]  (in the 2nd location)  2-4 cm, linear and entire leaves.

Note non-flowering plants can be distinguished from other smooth-leaved submerged aquatics (e.g. quillwort) by the compressed leaves, which have 2 hollow tube in section. (vs 4 hollow tube in Isoetes lacustris, quillwort)

[055]  (in the 2nd location) The underside of the leaves. Note where the roots emerged from the plants.

[056]  (in the 2nd location) The bract of the plant.

[088] (in the first location) A long flower stalk emerging from the water.

[064] (in the first location) A flowering plant. Glabrous, erect perennial, can grows to 60 cm.

[203] (in the 3rd location) A whole plant could be seen clearly now as the shore is exposed due to a very dry summer.

[195] Different stages of flower buds. (in the 3rd location)

[076] (in the first location) Flowers 12-20 mm, 3-10 in lax. (3 in the above photo)

[075] (in the first location) Elongated inflorescence, flower nodding.

[073_1] (in the first location) Corolla tube pale lilac 丁香紫色，淡紫色（介於粉紅色和紫色之間）with 5 petal lobes. It could be see that the corolla tube is quite angular near the base from this angle.

[075_1] (in the first location) Side view of the flower.

[067_1] (in the first location)

[076_1] (in the first location) Corolla tube is split almost to the base exposing the stamen and the stigma.

Note the flower is protandrous 雄蕊先熟的, style and stigma are still short and hidden inside the anther tube and could not be seen during the first male stage of the flower. In the above photo, the yellow stigma could be seen, indicating that it is now the second female stage, with style and stigma is now emerging from the anther tube.

[068_1] (in the first location) Br: bracts. Note: there are no bracteoles in this species.

[078_1] (in the first location) A rather frontal view of the flower showing different structures. CoT: corolla tube, CoTS: corolla tube is split almost to the base exposing the stamen, FuA: fused anthers, PeLL: 2 narrow petal lobes in the upper lip, PeLU: 3 larger petal lobes in the lower lip, Sti: stigma.

[052_1] (in the first location) A flower with petals withered, reviewing its inner structure.

AnB: anther beard, FuA: fused anthers, FuF: fused filaments forming an anther tube, staminal tube or a monadelphous tube 單體雄蕊, Hy: hypanthium 被絲托, 花托, 萼筒, Ino: inferior ovary, Sel: sepal lobes, Sti: stigma, Sty: style.

[057_1] (in the first location) Another flower with petals withered, reviewing the anther tube and the central style and stigma. Note it is now clearly see that the stigma (the yellow parts at the far left end of the flower) is bi-lobed.

[056_1] (in the first location) A young fruit.

[106_1] (in the 2nd location) It start turning brown when the fruit ripes.

[021]  (in the first location)It turns brown when the fruit ripes. (in the 2nd location)

Isoetes lacustris

Common name: Quillwort
Scientific name: Isoetes lacustris 
Genus: Isoetes 水韭屬
Family: Isoetaceae 水韭科, quillwort family

Remarks:

Origin: native

Note: Isoetes lacustris, squillwort and Isoetes echinospora, spring quillwort looks very similar in appearance and they could occur in the same lake. They could only be distinguished accurately by microscopic examination of their megaspores. 

Reference: https://bsbi.org/learn/resources/plant-crib/isoetes

The following individuals seems to be the former one but it needs microscopic examination to confirm its identity. 

Date: 13th Aug

[177] A lot of quillworts found in shallow water of a lake. It is said that it is usually present in some quantity, forming a dense turf on deeper lake bottoms. (vs Isoetes echinospora, spring quillwort usually scattered though rarely forming continuous swards)

[174] A submerged evergreen aquatic plant. It is found in acidic, clear-water lakes from marginal shallows to about 5m. (The depth of the lake these plants were found was 3m in average.)

[181] A rosette of smooth, cylindrical, sheathing leaves.

[182] Upright, spreading clusters of more or less straight, rigid leaves emerging from a rooted 'corm'.

[180] Note that a water lobelia, Lobelia dortmanna 水生半邊蓮*  is found left to a quillwort and a comparison could be made between their apperances, especially their leaves. (Note '水生半邊蓮 ' is not an official chinese name for this species, it is only suggested by a Taiwanese website).

[178] Leaves erect, sometimes recurved 反曲的 (i.e. 葉端向外、向下翻卷) (vs leaves initially erect, but soon bending away from the centre of the rosette, often appressed to the substrate (looking starfish-like) in Isoetes echinospora, spring quillwort.) 

[154] A detached plant near the shore of the lake.

[165] More detached plants are found.

[166] Detached leaves are found as well.

[155] Leaves somewhat brittle, remaining stiff when taken out of the water vs flaccid and clinging together when taken out of the water in Isoetes echinospora, spring quillwort.) 

[164] Leaf 10-45 cm long, c. 2.5-12 mm wide, cylindrical to varying degrees. (vs leaf 3-25 cm long, c. 2.5-3 mm wide near the base, with a perceivably slightly flattened adaxial face in Isoetes echinospora, spring quillwort.)

[173] Take a detached plant from the shore to have a closer examination.

[172] The lower part of the leaves are white and a bit transparent (It is white maybe because it died for a while) . It seems there are some transverse septum found along the whole length of the leaves.

[159] Middle part of a leaf, it becomes more greenish.

[154_1] Leaf parallel-sided and tapering only slightly (abruptly tapered) in the last few centimetres towards a rather blunt asymmetrical point (vs tapering almost immediately from the base to a slender, acute apex (tapering gradually to an cute tip) in Isoetes echinospora, spring quillwort.)

[154_2] Tapering abruptly at the leaf apex.

[157] Upright, spreading clusters of more or less straight, rigid leaves emerging from a rooted 'corm'.

[160] Leaf base is spoon-shaped, reviewing its true identity as a quillwort. The photo above also show the fibrous roots.

[158] Another closer examination to show the swollen leaf base.

[162] Need to peel off the outer leaf (sporophyll 孢子葉) to see the sporangium.

[162_1] Photo cropped above to show the ligule (Li), megasporangium (Mm) and megaspores (Me) found at the inner surface of leaf base. 

[162_2] A much more magnified photo to show the megaspores (orange dashed line).

Megaspores 500-570 micrometres diameter, the mature spore wall showing anastomosing 網結的 that resemble brain-coral ridges (x20 lens) (vs megaspores 420-450 micrometres diameter, densely spiny on all faces (x20 lens, only seen when dry and mature, i.e. late summer and autumn) in Isoetes echinospora, spring quillwort.)

[170] Another leaf come from a washed-up specimen.

[170_1] Cropped photo above to show the megasporangium (Mm) and megaspores (Me).