CONTENTS
Flora index
Fauna index
guide to the mangroves of singapore
Insects
Peter K L Ng and N Sivasothi (editors)
  Ants
Family Formicidae


Many ants are common in mangroves, but not all are obligates and are found inland as well, like Oecophylla smaragdina, the Kerengga and, which is also common in back mangroves. Crematogaster sp. and Dolichoderus sp. are foliage-dwelling pastoralists, i.e., they are found on vegetation and are symbiotic with another insect which they farm like cattle. They provide protection to scale insects (or lac scales) which secrete a sweet substance that the ants consume. These sort of ants are likely to be attracted to certain plants in mangroves which secrete sweet substances, e.g., Hibiscus tiliaceus and Sonneratia alba, and by their presence, help protect it against herbivores.

Crematogaster sp.
Size:
3 mm

Members of this species-rich genus nest in cavities. This ant has a small sting and exudes a repellent.

It is common on the underside of leaves of the Sea Hibiscus (Hibiscus tiliaceus), feeding on the slot-like nectaries of the thick veins at the base of the leaves.


  close up of ants and jumping plant lice larvae
Crematogaster feeding on the slot-like nectaries of Hibiscus.

The white insects are larvae of a Jumping plant lice (Mesohomotoma hibisci, Order Hemiptera Family Psyllidae), common on the Sea Hibiscus. They later undergo metamorphosis to become winged adults.

close-up of ants
Odontomachus malignus
Odontomachus malignus
Size:
6 mm

This is a well-known intertidal ant, which is a ground rather than foliage dweller, nesting underground in mud lobster mounds. This ant gets its name from its very nasty sting!

close-up of adult Tetraponera sp.
Size:
5 mm
A distinctive long bodied ant, it lives in hollow twigs and predates on small invertebrates.
close-up of dissected twig
Sectioned twig to reveal
larvae and adults
It protects itself with a powerful sting, but it is not as bad as Odontomachus!


Webbed-leaf nest
Polyrachis bicolor
Size:
7 mm
The most common ant on mangrove foliage, which it webs to form nests.
Eggs and adult ants
It defends itself by biting and spraying acid. These ants produce sound, as does Dolichoderus.


Ants attending to
their 'herd' of lac-scales
Dolichoderus sp.
Size:
4 mm
Has a distinctive smelling repellent, and is a pastoralist of lac scales, Tachardina aurantiaca.
Male and female lac scales
The reddish-yellow scales are wingless females; the smaller red ones will emerge as flying males. Shellac is a resinous substance made by roasting twigs with the insects and shaken onto metal plates. Used as a varnish, in paints, inks, sealants and on old phonographic records.

<<Back to insects
What is mangrove?
Introduction

The Ecosystem

Abiotic
Biotic

Value
Intro
Products
Indirect uses
Potential uses

About Mangroves
in Singapore

History
Mangroves to visit
Conservation
 
From "A Guide to Mangroves of Singapore", Peter K. L. Ng and N. Sivasothi (editors)
Volume 1: The Ecosystem and Plant Diversity and Volume 2: Animal Diversity
Authors: Kelvin K. P. Lim, Dennis H. Murphy, T. Morgany, N. Sivasothi, Peter K. L. Ng,
B. C. Soong, Hugh T. W. Tan, K. S. Tan & T. K. Tan
BP Guide to Nature Series published by the Singapore Science Centre, sponsored by British Petroleum
2001 Raffles Museum of Biodiversity Research, The National University of Singapore & The Singapore Science Centre