Thursday, January 17, 2013

Wait! There's more!!

The silly season kept me busy with other things but I still kept a watchful eye on my Mantid Microcosm and have been taking photos too...of course! So now I think it is time to update you on what is going on in the world of mantids, spiders, plant hoppers and ladybeetles. But wait...there's more! The Cumquat tree seems to be attracting all kinds of mini-beasts or invertebrates or bugs; doesn't matter what you call them as long as you know what I mean!

Things had been  going along as normal with the two mantids on the Hydrangea bushes, one, or maybe two, actually when I went out at night to look I found seven!...on the Cumquat tree and still the one on the Hydrangea behind the two main ones. Then recently I found a new threat to my fruit on the tree; a Spined Citrus Bug - Biprorulus bibax. These suck the juice from the rind of the citrus and cause damage such as browning and eventually fruit drop. So, although these are very interesting looking bugs, I was not thrilled to find them on my Cumquat tree!

Now I think the mystery of the eggs can be solved at last! I looked up my little book on citrus pests and found a photo of the eggs of this bug and guess what? Yes, the same as our mystery eggs! It lists their major natural enemies as small parasitic wasps called Trissolcus oenone, which paristise the eggs and a predatory assassin bug, Pristhesancus plagipennis.  I thought some of the mystery eggs had been parasitised and I think that may be correct. There are very many little flying wasps around the garden and I wouldn't doubt some of them came out of those eggs! Nature has a way of working things out sometimes.


Spined Citrus bug - Biprorulus bibax, sub-adult (not yet spined)
on Cumquat Image: © Kim Sinclair


















As you can see from the later photo, I found the bug, actually two of them, again but now they are adults and have their nasty looking spines. They would blend in well on my Lisbon Lemon tree since it sports very nasty spines that I often prick myself with when pruning, but I haven't seen any on there as yet. 
I decided to capture them to prevent their spread from occurring to the lemon and also to protect my two orange trees which are developing fruit. Now that the bugs have wings, yes there are wings under there now, it is tricky to take photos since occasionally they just take off but not very far thankfully! 


Adult spined citrus bug


Damaged cumquat fruit. 
As well as the Spined Citrus bugs attacking the fruit, there are quite a few Katydids of various stages on the tree too. They eat the leaves and flowers and also bite pieces out of young fruit, causing a large chalky-white scar and fruit drop. So, another assault on the poor Cumquat tree! My book only lists a tachnid fly  and wasp parasites as their natural enemy but despite their camouflage, I am hoping that birds, spiders or my mantids might decide to have one for a meal! All of these predators have very sharp eyes so let us hope they help keep the population down somewhat.


Katydid nymph - early instar.

Pre-adult Katydid-Caedicia simplex nymph

See how the Katydids change their appearance as they grow. However, they still have those very long antennae even when their body is very small. And look at those big rear legs suited for jumping from leaf to leaf for food or to escape a predator. This small one is on the Hydrangea leaf but later I found them on the Cumquat tree. The adult can fly so can move from plant to plant quite easily.

Adult Katydid - Caedicia simplex blending in very well with the foliage.

The last thing I want to share with you about the Microcosm this post is the disappearance of the many Salticidae spiders. I know I mentioned this before but have only seen one saltie in that area in recent weeks although there are some other small spiders who spin small webs to catch their prey. I didn't think much of this fact until I saw a post on Facebook recently by Minibeast Wildlife of the jumping spiders they found in a Mud Dauber wasp's nest they accidentally smashed. It seems the spiders are paralysed by the wasps then placed in the nest for the developing wasp larvae. I happen to have a small mud dauber wasp nest right near the Microcosm that I had not yet mentioned since I was hoping to get a photo of the builder first. I actually saw the wasp leaving the nest recently but it is rarely around. Hopefully I will be able to tell you more about this in the future.

I regret that technical and family circumstances prevented me from posting earlier so I feel I could write much more but think this is enough for now and, all going well, I will post again much sooner next time! See you then! 

Reference:
Citrus Pests - A Field Guide. (A Companion to Citrus Pests and their natural enemies: Integrated Pest Management in Australia) Smith, D., Broadley, R., Feutrill, C., Beattie, A., and Freebairn, C. (Eds). 1997.  Department of Primary Industries, Brisbane and Horticultural Research and Development Corporation, Sydney. 

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