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A situation has arisen recently that is worthy of note here.
A large stick insect, the Giant Spiny Stick insect, Eurycantha calcarata Lucas, has been found for sale in Melbourne & Sydney pet stores. This impressive species is related to the famous Lord Howe Stick Insect, Dryococelus australis (Montrouzier). The similarity of the two is quite obvious. You can check the two in Brock and Hasenpusch’s book listed below.
An adult make of the Giant Spiny Stick Insect.
An Adult female of the Giant Spiny Stick Insect.
This species, like offerings in many pet shops, does not make a good pet. When disturbed, males raise the hind legs and emit a powerful smelly secretion from the tip of the abdomen. This problem is that fingers get caught between the hind tibia and femur; the hooks on the latter can penetrate the skin to the bone. So this is not a good pet, and especially not suitable for small children. In New Guinea local people are known to use the hind legs of a related species with bigger spines as fish hooks. So these spines are formidable defence weapons for this stick.
Hind leg of an adult male. Note the robust recurved spine.
The problem with this stick insect in Australia is that it is not really certain that this insect actually occurs in Australia. The original species description was said to include specimens from Cape York, but to date no "reliable" specimens have been found naturally in Australia. There could have been an error in labelling all those years ago and the specimens included in the original description may not have actually come from Australia. Dozens of expeditions to Cape York by all sorts of biologists have occurred over the years but no one has ever collected one of these giants.
Nymphs (subadults) of the Giant Spiny Stick Insect.
When questioned, the collector of the specimens found in Melbourne pet shops claims he found them in the Hopevale area. (Hopevale is not far from Cooktown, Qld.) This is a popular collecting locality for entomologists. No other Giant Spiny Stick Insects have turned up in any collections form there.
The most likely scenario is that eggs of this species were smuggled into Australia from Papua New Guinea where the species is not uncommon. But because the original description states that some specimens were from Cape York, it is not illegal to possess them or sell them in pet shops in Australia because they may actually come from Cape York if the collector is telling the truth.
An important issue looms. This species is primarily a ground-dwelling stick. However, a potential economic problem may develop because the Giant Spiny Stick Insect feeds on palms and is a pest of Coconuts and Oil Palms in PNG. Australia has several hundred native palm species and a large number of introduced palms grown in parks and gardens etc. If this insect is alien to Australia, it could end up adapting to tropical Australia and become a pest.
Geneticists are attempting to use DNA sequencing to determine if the Australian specimens actually came from New Guinea populations. If so, there is a good case to prevent further sale of the species and destroy the known living cultures in this country.
This is an important case for several reasons. I guess it is possible for a few small eggs to get by the X-ray machines in airports. If so, some tightening up is necessary because of potential “agricultural sabotage” by unscrupulous individuals. Also it shows how easily something of potential economic concern can slip through the system. With the relatively recent introduction of Fire Ants and the Electric Ants to Australia, and the potential damage they can cause, there is a good case for strengthening the surveillance of goods coming into this country. With the huge numbers of containers entering the country from many ports, complete surveillance may never be possible. However, I suspect thorough checking has a relatively low priority with governments these days. Agricultural concerns seem to be of minor consideration.
Literature.
Brock, P. D., Hasenpusch, J., 2009. The Complete Guide to Stick and Leaf Insects of Australaiia. CSIRO Publications, Collingwood, Vic. 204 pp.
Garden Miscellany
A number of “creatures of interest" have appeared in the past few days and here they are!
The flowering of one of our Amorphophallus plants (see Aroids) has attracted some interested observers. This Rove beetle, is active by day and its slow swooping flights can be frequently seen, especially if a Cane Toad, for example, has been killed in the driveway or run over by the mower. It is more colourful than most Rove beetles. It is said to be a predator and so would be looking for prey at a source that would attract them, like a stinky Amorphophallus flower.
The Rove Beetle, Actinus macleayi, family Staphylinidae.
St Andrew’s Cross Spider, Argiope keyserlingi is a widespread spider and everyone who is observant in the garden has seen it. The X is called a “stabilimentum” and apparently has a number of functions. It is thought to attract insects. It’s silk is different from the rest of the web and reflects UV light that may attract pollinating insects using UV to find flowers. It is also hypothesized that it helps the spider to camouflage itself and additionally warns birds that there is a web there. When annoyed, the spider shakes the web vigorously and the startle effect of the “X” may help in convince the attacker that it should move on.
St Andrew's Cross Spider, Argiope keyserlingi in its web.
A case of mistaken identity
I was surprised when this creature appeared at the light. At first I thought it was an odd Milionia queenslandica Jordan and Rothchild. A closer look revealed it was a butterfly. The Purple Dusk-flat, Chaetocneme porphyropsis (Meyrick & Lower) is a skipper butterfly with a very restricted geographic distribution. It is known from from Cape Tribulation to the Paluma Range near Townsville. The caterpillars feed on several rainforest trees and at least one introduce tree, Cinnamomum camphora. See Braby (2000: 68).
The Purple Dusk-flat, Chaetocneme porphyropis, family Hesperiidae; Pyrginae
Milionia queenslandica Jordan and Rothchild, family Geometridae, Ennominae.
Similarities don’t end there.
This little moth, Synechodes coniophora, is active during the day flying like the wind and alights only for a fraction of a second. It also flies at night since the moth is found occasionally at the lights. The caterpillars bore into the stems of palm flowers and fruits, especially Lawyer palms, Calamus spp. I find them buzzing around the giant Oil Palm we have in our driveway.
Synechodes coniophora Turner; family Brachodidae.
Love Bugs, flies of the family Bibionidae, Plecia ornaticornis ( see Love Bugs)are commonly seen on flowers during the day and around lights at night. They seem to be shunned by vertebrate and invertebrate predators alike. Ants avoid them. Birds leave them on the light sheet and my friend the Boyd’s Forest Dragon doesn’t touch them. Their similarity to the Synechodes moth is striking but the resemblances don’t end there. The cantharid beetle fits these criteria too. They are probably part of a Mullerian Mimicry Complex. See Mullerian Mimicry).
Plecia ornaticornis; family Bibionidae
Elegance in moths!
Barnatola panarista (Turner) has been seen on this site before but it is a beaut little moth. Nothing is known of its biology.
Barantola panarista (Turner); family Depressariidae.
Luxuriating Turkeys
These turkeys are taking advantage of the warm spring weather to do a bit of “anting”. They lay down in the sun and expose their feathers and look very silly. The warmth of the sun kills lice (Mallophaga) that live on the feather shafts. These parasitic insects are very sensitive to temperature. They die if it varies only a degree or two. That’s why bird lice don’t survive for long on humans. We are just too cold for them.
All but unconscious in the sun!
References
Braby, M. 2000. Butterflies of Australia: Their Identification, Biology and Distribution. Volume one. CSIRO Publications, Collingwood, Vic. 457 pp.
Nature observations in a Rainforest in Kuranda, Queensland, Australia, Subscribe to this blog: bunyipco-subscribe@yahoogroups.com