BunyipCo: April 2018

Monday, 30 April 2018

Nice Cricket, Awful Name

Pseudotrigonidium australis (Chopard), adult male in typical pose

This little cricket was described by Lucien Chopard, a legendary French entomologist in 1955 as Tremellia australis. Fair enough. The name is simple and easy to remember. But in 1999 a Russian entomologist taxonomically massaged the tribe resulting in a lot of splitting. Tremellia was redefined and T. australis did not fit the new concept of Tremellia. So it was transferred to the larger genus Pseudotrigonidium. Further he established subgenera within Pseudotrigonidium, but apparently left the sole Australian example, T. australis, and a couple of other species from Borneo, in neither of the two allotted subgenera. So it becomes Pseudotrigonidium australis (Chopard)- the Kuranda Tree Runner.

In dealing with this taxon for the Guide to Australian Crickets to be published by CSIRO, we had to try and discover what the species really looked like. The type was an old specimen, tattered and discoloured and without precise locality date. Otte and Alexander in their monograph collected some specimens from near Kuranda.

As luck would have it, the species was discovered literally in my own backyard. The living crickets look nothing like the type nor the preserved specimen collected by Otte and Alexander in 1960.

When viewed closely, the crickets are very colourful with brown and yellow markings seemingly aiding in camouflage.

Even the head is distinctive with stripes and light-coloured patches. In life the eyes have a greenish tinge.

Pseudotrigonidium australis (Chopard), adult male in typical pose

The crickets have a very distinctive posture. They always are directed downwards, legs askew.They have extremely long antennae and excellent eyesight. The antennae are in constant motion. When disturbed they dart downwards but in a spiral fashion to attempt to confuse the predator. Since they cannot fly, the utilise both their colour pattern as the first line of defence followed by their extremely fast movements.

Males sing from tree trunks after dark. This continues through most of the night into the pre-dawn hours if the weather is warm and not too wet. Adults and nymphs can be found on the same tree trunk. It is interesting that not all trees are inhabited by the crickets. If there is a pattern, the desired trees have furrowed bark and have some growth of lichens. Also the diameter of the tree does not fit a pattern. Trees of 8-9 cm can have crickets as well as those 10 times that diameter. Females supposedly lay their eggs in the cracks in the bark. These crickets occur from the Daintree south to the Kuranda Ranges. We have not found them in the Atherton Tablelands.

Sunday, 22 April 2018

End of the Line

It's that time of year when some of the big Golden Orb Weavers are in their last days. They neglect their webs and do not eat very much. Males are not found and females descend to the ground to lay their eggs. In addition, Black Butcherbirds seek them out and pull them from their webs. During previous weeks, the spiders seem to avoid being picked off by the birds. Perhaps, the untidy webs are a giveaway for the spiders late in the lives of the orb weavers.

They are beautiful spiders when you see them up close. And they can see you. They are quick to dart to the we's edge when you approach.

Friday, 13 April 2018

Cassowary Update

The three youngsters are still growing and they still continue their characteristic peeping. This becomes more enthusiastic when the food source is is to their liking.

But the end is neigh. The chicks are just about the right size for their lives to make the next change. That occurs when Pops decides enough is enough and he drives them away. This seems sad because the chicks do not seem to understand what is going on with their father. He was protective and attendant yesterday but today he is antagonistic. Actually this behaviour may be initiated by the female when she comes into season.

Nice garden bird, eh?

Some colours beginning to appear and the wattles are developing

Wednesday, 4 April 2018

New Book

A new book has appeared on the scene and most people reading this post would probably not be aware of it because it is published privately.

Lynette Esnor has produced a very handsome volume, number 3 in her series. This one features birds of Northwest Queensland. The other volumes include #1 The Wet Tropics, Queensland, #2 The Gulf of Carpentaria, Queensland. Another volume is in the offing and the topic will be the brids of the Cape York Peninsula, Queensland.

The book is comprehensive in the sense that it, and the other volumes contain an introductory section featuring the History of Bird Evolution, Anatomy and Physiology, Adaptations (in considerable detail)Torpor, Feeding Habits, Preening, Feather and Plumage, Senses, Seasons, Mating and Nesting, Family Life, Migration and Distribution. Most of these topics are generally not covered in other volumes and they are of interest to the casual birder. A glossary and comprehensive index are also included.

The volume is attractively presented and features Lyn's photos in the 205 pages. Detailed notes accompany each species.

My Bird Obsession is published privately and can be ordered from Lyn at her email address: Lynette Ensor