Aliens IV: Infestation

Those who are fans of sci-fi will know that when aliens invade earth they multiply in egg-shaped sacs hidden somewhere safe like in an underground cave or cellar. Those sacs may or may not contain a human host on which the developing alien might feed.

The photo above taken recently could be of a terror (the new collective noun for aliens) of extraterrestrials or it could simply be a group of Hemipterans (true bugs) hatching on a Poa sp. seed head. Hemiptera is an order of insects that includes cicadas, leafhoppers and aphids, which are distinguished by common sucking mouthparts. All insects in this order either suck on the sap of plants (below right) or on other insects (below left).

Gumtree Bug instar sucking sap

Hemipterans do not undergo a complete metamorphosis, changing from a caterpillar to an adult, as moths and butterflies do. Instead they are born looking similar to the adult and progress to that state through a series of ‘moultings’. This is known as hemimetabolism or partial metamorphosis.

Pictured (top) is a species of Stink Bug. The newly hatched young (known as instars) look very similar to the adult but lack the wings. There are five stages of ‘moulting’ before the adult emerges. The 1st instars do not move far from the egg shells. Their food source is the bacteria left on the egg shell by the female adult when the eggs were laid. After the first moulting, the young (2nd instar) will wander off to look for food.

Assassin Bug sucking on a beetle

Both the instars and adult stink bugs (more politely known as Shield Bugs) will excrete a foul-smelling liquid when disturbed. This liquid deters predators such as wasps which paralyse the bug and use it as a host for its larvae.

I reckon this has the makings of an Alien movie blockbuster. I just need to work out who plays Ripley.