ABOVE: Hibiscus tiliaceous growing on Kinarut Beach just south of Kota Kinabalu in Sabah. The island in the background is Pulau Dinawan.

Two different species of small shrubby  seashore trees with yellow hibiscus flowers grow  on sandy shores around the coast of Borneo. Thespesia populnea and Hibiscus tiliaceous.

Hibiscus tiliaceous grows on almost every beach whilst Thespesia populnea is relative rare.

Both species produce yellow flowers with a deep crimson center. The yellow petals turn deep pink over 24 hours. These two  very similar species  can be distinguished as follows;

1. Both produce dry capsules  filled with tiny seeds. The capsules of Hibiscus tiliaceous split open (dehisce) when ripe whereas the capsules of Hibiscus tiliaceous  only split slightly.

2. The veins on the underside of the leaf where they join the petiole (leaf stalk)  of Hibiscus tiliaceous  have  very variable ant attracting glands  which are absent in  Thespesia populnea

Hibiscus tiliaceous IMG_0098

Hibiscus tiliaceous IMG_0099.JPG
Note the gland on the midribs as they join the leaf stalk. Small black ants often feed on the exudate of these glands. In return for the exudate the ants protect the leaf from being eaten by moth or butterfly larvae. The presence of glands is a useful distinguishing feature  between Hibiscus tiliaceus and Hibiscus populinea.

Hibiscus tiliaceous  IMG_0092.JPG