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Thursday 24 May 2012

What 24 Mega Pixels Can Do

On a recent trip up the road to the mixed eucalypt-acacia woodlands I was wandering about at night with my camera and saw a familiar site. A pyralid male was signaling. I am familiar with sound-producing pyralids because of the encounter with Syntonrarcha iriastis Meyrick. This moth has been observed and written about by Gwynne and Edwards (see below) from observations made in Kings Park, Perth.

I have picked up stridulating moths with the mini bat detector on a number of occasions. This time I was far away from my detector but thought the moth must be producing sound, so took a photo and collected the male. It turns out that it is Symmoracma minoralis (Snellen), another pyralid. It also has been extensively studied by Heller and Krahe from observations made in Malaysia. This moth ranges from northern Australia to Sri Lanka.

The purpose of this blog is not to go into detail about the sound production of this moth but to relate how wonderful digital photography can be. Details of sound production and its function in moths can be garnered from the paper above and the one below.

S. minoralis stridulating in the field at night.
 The same photo enlarged showing the genitalia, opened and revealing the stridulatory apparatus.
 The same photo more greatly enlarged showing the genitalia. The ribs are not part of a file-scraper system. According to the hypothesis of Heller and Krahe, the system produces sound as a tymbal through muscular contractions with the white opening acting as a sound chamber. Contractions cause the sound! The other moth, S. iriastis, seems to produce sound in a similar fashion but has very different structures to do it.
 S. minoralis, the moth pinned and with the genitalia retracted. A rather plain moth with a fantastic biology.

The power of mega pixels!

Literature
Gwynne, D. t., Edwards, E. D. 1986. Ultrasound production by genital stridulation in Syntonarcha iriastis Meyrick (Lepidoptera: Pyalidae): Long distance signalling by male moths? Journal of the Linnaean Society, 88: 363-376.

Tuesday 22 May 2012

Bug Blog

A certain professor and a colleague have been calling for "more bugs" on the blog so here goes. Firstly for the non-entomological types, especially the North Americans, all insects are not "bugs" but all bugs are insects.

Simply put, a bug is an insect that has sucking, not chewing, mouthparts and has gradual metamorphosis. When winged, the forewing is divided, half is membranous, the other half is hardened.
They are members of the order Hemiptera (in the olde sense!)

So here goes, tropical bugs.

 Coreidae: Sciophyrella australicus
 Largidae: Physopelta gutta
 Alydidae: Riptortus sp.
 Undetermined bug with newly hatched bug-lings
 Reduviidae: Harptacorinae: Euagorus dorycus  feeding on another bug
 Reduviidae: Pristhesancus plagipennis sharing caterpillar food with ants
 Note the beakwork
 After feeding, the ants continue the mop up.
 Tessaratomidae: Cumare pallida. Tessaratomids are bugs that look after their eggs an young. See the detailed study by Monteith below for details. A very interesting group in Australia.
Tessaratomidae: Lyramorpha parens. We have dealt with this one before. 
 Tessaratomidae: Lyramorpha parens guarding young.
 Probably Pentatomidae: Bromocoris souefi, a nymph but it could be a pentatomid as well.

Reduviidae: Harpactacorinae, undetermined genus, perhaps Helonotus
Pyrrhocoridae: Dindymus sp mating
 Pyrrhocoridae: Dindymus sp. Slight different colour morph.
 >Pentatomidae: nymph on Grass Tree, Xanthorrhoea  at night
 Pentatomidae: Poecilometis eximus mating on Grass Tree


Thanks to Tom Weir and G. Cassis for help with the identifications. Any errors are not theirs.

Literature

Monteith, G. B. 2006. Maternal Care in Australian oncomerine shield bugs (Insecta, Heteroptera, Tessaratomidae). Denisia 19, zugliech Kataloge der OO, Landesmuseen Neue Serie 50: 1135-1152.

Tuesday 15 May 2012

Night Walk On The Mt Lewis Road

It's autumn in the tropics. This means reduced rainfall and slightly cooler temperatures. The thing that impresses me is how quickly the season changes and the effect it has on the biota. It seems like in a matter of a couple of weeks, numbers crash and species disappear from the scene.

A walk on the lowers slopes of Mt Lewis, near Julatten, yielded a few insects, but in general, there was not much about.

 Allacta australiensis Roth: Ectobiidae; Pseudophyllodromiinae. This blattodean is found only on tree trunks. It lives in cracks in the bark during the day and emerges at night. It occurs from Cooktown south to the Babinda region including the Atherton Tableland.
 Beybienkoa fuscofemurifera Roth: Ectobiidae; Blattellinae. This species has a rather restricted known distribution with specimens from the Daintree Region and Mt Lewis.
Anaplecta calosoma Shelford): Ectobiidae; Anaplectinae. This is a small roach, measuring a little over 5 mm in length. Misidentified in the first instance. I'm surprised no one picked up on this!

 Amusurgus minmirri Otte and Alexander: Gryllidae: Trigonidiinae; Trigonidiini. Two members of the same genus found on weedy vegetation on the road after dark. Normally they spend the day in leaf litter.
 Amusurgus tinka Otte and Alexander: Gryllidae; Trigonidiinae; Trigonidiini.
 Trigonidium sp. Gryllidae; Trigonidiinae; Trigonidiini.  This may represent a new species
 Mjobergella sp. Gryllidae; Landrevinae; Landrevini. Lives on the forest floor.

Genus? Gryllacrididae. Note the checkered patach at the base of the fore wings.
The Raspberry Sawfly, Philomastix macleaii, on its host. For more on Sawflies, have a look.

 The business end of a Click Beetle, Elateridae
 A Rove Beete, Actinus macleayi, Staphylinidae; Staphylininae
 Head shot
 A Darkling Beetle, Tenebrionidae, probably Promethisis sp.
An anthelid moth before it's a moth!

Wednesday 9 May 2012

It Must Be Snake Season

We have seen more snakes in the past few weeks than at anytime during the summer. It is a rather warm autumn but this seems unusual to me.

The Green Tree Snake, Dendrolaphis punctulata, can reach 2m in length. This fellow was less than that, about 80cm in length; It is a diurnal snake and feeds on frogs, small reptiles and some mice. It's an egg layer and is harmless, though a bit feisty when annoyed. It is one of the few members of the Colubridae that we have. Most of the baddies are in the Elapidae.

Even during the day you must be careful where you place your hands!





Now That's a Snake

There are some hazards in being a student. This snake was found on the Smithfield Campus of James Cook University. It is an Amethystine Python, a male, and makes the one observed at my place (seen below) a Vinegar Eel by  comparison.
 Gary Wilson photo
Gary Wilson Photo

Saturday 5 May 2012

Fellow Traveller

The Asian House Gecko, Hemidactylus frenatus, is a common commensal with those of us living in the tropics. It has a much more extensive range than the tropics. It has been recorded from every Australian state and is widespread in the tropical world, being moved around by commerce. The first known occurrence of this lizard in Australia was in 1845. This gecko lives insides homes and is often tolerated because it feeds on unwanted insects and spiders and is a bit of a curiosity. They produce a characteristic call that is audible from several metres. It is not the only gecko that produces sound, however. Many geckos are vocal.

This Asian House Gecko is carrying a number of parasitic mites. These are probably Red Gecko Mites, Geckobia bataviensis, a species that lives on the toes of geckos and that can transmit disease.
Asian House Geckos live inside and outside the house but don't seem to venture very far into nature. Predators probably take their toll. Many people see them like this clinging to a window awaiting insects attracted to to the lights from within. (Sorry about the photos, folks. It's hard to get close to these guys)
But how do geckos cling to ceiling, walls, glass etc? Aristotle was taken with the mechanism but he did not discover the real mechanism. In fact, it was only relatively recently that the true explanation has come to the fore. Geckos have millions of fibres on the pads of their feet.  Each has a minute suction cup at the tip. In combination they have the power to hold the lizard to its substrate. But then how do they detach themselves? Apparently it's as simple as simultaneously changing the angle of the suction cup and the pads detach. Commerce has produced a new adhesive utilising the technique of millions of fibres that can attach to any substrate, smooth or rough.

This is a very young Asian House Gecko. Females lay eggs in drawers, between cushions in sofas or in any number of concealed spots. Two eggs are laid in each clutch. If successful, the Asian House Gecko can live for about five years. But in the house they face a multitude of problems including lack of food and water, desiccation, cats and the most efficient predator of all-- the vacuum cleaner!

Thursday 3 May 2012

Rat Patrol

Well it's that time of year again when things cool down a bit and the rats become active. So do the pythons.
We heard a commotion the other morning just on dawn and observed this big, thick  Amethystine Python making a beeline for someplace in particular. He had a cadre of birds and a Brush Turkey in tow but got to a tree and gingerly crawled up at a pretty good rate for such a big snake (more than 3m in our estimation) It chose a flimsy branch and stretched out and crawled on our roof. After that our vision was obscured--probably fortunately! He probably was heading for his favourite winter spot in the roof or was able to smell "rats". In any case, he(or she) just seemed to disappear-all in the space of about 5 minutes.

 Heading to our house


 A rather well fed individual
The iridescence gives the Amethystine is name