12 January 2009

More mangrove stories at Semakau

Dr Jean Yong is a treasure of marvellous mangrove information which he freely shares. We very gratefully tried to absorb and learn as much as we could.
Walking the mangroves with him is such a learning experience as all the strange plants become friends we know by name.

This pretty plant with long stems and sprinkled with white flowers is often seen draped on all kinds of coastal plants, giving the area a bridal feel. This is Cassytha filiformis which is a parasite that has no leaves. Host plants includes a wide variety of plants but they seem to particularly like Bruguiera gymnorrhiza. The young parasite produces a fine twining stem which snakes along until it finds a host. It then pierces the host with modified roots and lives off the fluids of the host. Ouch.This is Flagellaria indica, a pretty climbing vine found along the shores. It appears to have many traditional medicinal uses in our region.This is Dischidia sp. also known as the Ant House Plant. This odd plant is often seen perched on mangrove and coastal trees. It has special modified leaves that inflate into hollow oval-shaped chambers. Ants soon take up residence inside these chambers. While the ants get a ready-made home, the plant gets access to scarce minerals from the ants' wastes and left overs that build up inside the modified leaf! Wow!

Dr Jean Yong also patiently points out some distinguishing features of the confusingly similar Rhizophora species.He illustrates with examples how, compared to the other parts of the brown 'fruit' (e.g., the stalk and the little pointy things at the top of the 'fruit'), Rhizophora stylosa has a smaller 'fruit' (left in the photo), while Rhizophora mucronata has a larger 'fruit' (right in the photo). Shufen (who is holding the two examples) shares that the brown thing is called a 'fruit' before the propagule (seedling thingie) grows out, and is called the 'calyx' after that. Sigh. Botanical terms can be challenging.

Dr Jean Yong also shared a marvellous way of telling apart Rhizophora apiculata from Rhizophora stylosa from a long distance away. Rhizophora stylosa (left tree in the photo) tends to have looping stilt roots without many aerial roots coming down from the branches, while Rhizophora apiculata (middle tree in the photo) has more aerial roots growing down from the branches.
Api api (Rhizophora mucronata)
The overall effect is that Rhizophora apiculata looks like a more daring girl who lifts up her skirts to show her ankles (many ankles at that!). While Rhizophora stylosa is more demure and her skirt covers her ankles. Who can forget the difference after that analogy!