Monday, April 22, 2013

Dainty Flyers and Curious Nomads

The microcosm has seen many changes since my last post with the latest being the arrival, at last, of autumn. It was a long hot summer here which took its toll on all living things. Fortunately, the rain did eventually arrive so the garden needed less attention except for mowing lawn and pulling the many weeds that sprang up after the downpours!

I was fortunate to find some eggs and tiny caterpillars of the Dainty Swallowtail (Papilio anactus) butterfly on my citrus trees. I found some on the lemon, cumquat and on both orange trees but mostly on the healthier navel variety where I found the most. I brought some inside to care for and keep an eye on because despite the fact that they eat the leaves of my citrus, they don't seem to do any long term damage and I prefer them to survive to adult so I can see the beautiful butterflies in my garden.

Dainty Swallowtail egg
Dainty Swallowtail ~ Papilio anactus egg on tip of young leaf with small caterpillar in background.



I have raised these caterpillars before so knew they are very easy to look after, simply providing fresh citrus leaves often and ensuring there are good sturdy stems for them to attach their cremaster and girdle.

Swallowtail caterpillars attach their hind end to the stem with a cremaster which is a support hook or cluster of small hooks at the abdominal end, and then make a girdle of silk around their middle to hang from the stem. After a while they shed their skin for the final time and take the form of a chrysalis.

Inside the chrysalis the caterpillar's body completely reforms itself into that of a butterfly; a most amazing metamorphosis!

Here is a short video I made to demonstrate this wonderful life cycle.

I released five of these into the garden while the weather was still warm and since saw an occasional Dainty gently fluttering around the gardenm feeding on the Buddleia flowers and laying eggs on the citrus trees. However, I still have two pupa which I think will probably remain in their chrysalis until next spring. This is not uncommon in lepidoptera life cycles; they will overwinter at any stage - egg, caterpillar, chrysalis or butterfly/moth. I would think the chrysalis is the ideal stage as it has the most protection inside its casing which you can see is very well camouflaged in citrus tree green! 

Now, to other lepidoptera species in my microcosm; the Saunder's Case moth, a most fascinating species which lives its larval existence inside a casing made of silk and covered with short pieces of stick or leaves. We have had several of these creatures crawling around and feeding in our garden over the last year. I have mainly found them on the strappy plants called Dianella that you can see in the video in my back garden and also on the other strappy plants known as Dietes. However, these caterpillars seem to be able to live on many different host plants and wander around the garden to plants of their choice. 
The Pencil Pines next door also hosted a large number of these caterpillars which a flock of Currawongs found a delectable feed one day much to my amusement as they are stunning birds to watch in their aerial antics! 

Saunder's Case Moth on branch with long leafy
 pieces decorating its case.

Saunder's Case Moths are unusual in that the female never leaves the case even after pupating but mates with a male and lays eggs from within the casing. More information can be found HERE.
Below is a video of one of the casemoth caterpillars I found moving across the lawn. 


Since the insect season is almost at a standstill, future posts may have more about some larger residents of the garden; the local birds, which I have also found very interesting this year and hope to continue to see many different birds in and out of our microcosm.