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There she is at last

April 3, 2020

Q: What do you call a Feather-horned Beetle without the feathery antennae?

A: Female

It has been a good season for Feather-horned Beetles (Rhipicera sp.). The males (pictured left) with their impressive antennae have been flying for nearly two months (not continuously!) using these antennae to detect females. Last month a blog about these amazing looking creatures finished with the line ‘My challenge this year is to take a picture of the female beetle’ as I had never seen one. The female beetles have more rod-like antennae.

As the mating season draws to a close and the male beetles have all but gone I guess it is now safe for the female beetles to show themselves (pictured right) in public without being harassed because there are a few making an appearance.

Challenge complete.

Two metres up and feedin’ fine

April 1, 2020

Last month a blog featured an insect known as a Blue Ant (Diamma bicolor). It is a species of Flower Wasp so called because like most female flower wasps it is wingless and it is metallic blue in colour i.e. it looks like a blue ant. Flower Wasps are known for their sexual dimorphism. The male is generally much larger than the female. The male is also winged. Adult wasps are nectar feeders. To feed, the female mates with the male wasp who flies off and carries the female into the higher reaches of a plant where it can feed and mate at the same time. In the case of the Blue Ant the female is much larger than the male and the recent blog questioned how the female wasp gets up to the flowers given the male wasp physically is not big enough to fly her to a food source.

During a bird survey of a neighbour’s property I came across a Silver Banksia (Banksia marginata) in bloom. The flowers were swarming with pollinators. Lo and behold frantically dipping into the Banksia flowers with all the other bees, flies and beetles was a female Blue Ant (pictured). Although I did not see how it got there I assume it climbed the tree. The flowers were at least 2 m above the ground.

When last seen the Blue Ant had tangled with a Honey Bee and both had plummeted earthwards. I guess it has to climb back up.

Meet Mama

March 30, 2020

By far one of the most interesting insects in the Australian bush is the psyllid. A psyllid, also known as a Jumping Plant Louse, is a hemipteran, a sap sucking insect. This blog is littered with tales about psyllids but they have been exclusively about the nymphs. It’s time to meet the parents.

Adult psyllids (pictured above left) look like small cicadas and are about 3 mm long. They are winged but are poor fliers relying on the wind to transport them from plant to plant. After mating the female psyllid lays orange to brown coloured eggs on stalks, usually on the underside of leaves (pictured below). Most psyllid species are host specific, feeding on a small number of related plants. Plants such as eucalypts each have their own group of psyllid species. A psyllid may lay up to six generations of eggs in a year depending on the species.

When the eggs hatch the emergent nymphs construct a protective structure made of honeydew and wax under which they live. This structure known as a lerp protects the nymph from predators and dehydration. Pictured left is a Lace lerp  (Cardiaspina sp.) with the psyllid nymph underneath. Lerps can take many forms – conical pyramid, fairy floss, clam shell, etc. depending on the species of psyllid. The lerp in turn is a food source for birds such as pardalotes and bell miners and is an indigenous source of sugar. The nymph progresses through five stages before emerging as an adult.

The nymph feeding causes local discoloration of the leaf where the sap has been sucked (pictured right). Though not fatal to the leaf or the plant an explosion in a psyllid population can cause widespread ‘browning’ of trees and stunting of growth. In natural environments psyllid populations are kept in control by predators and the availability of food.

Nice parents, destructive kids.

Magnificent moth

March 26, 2020

While checking for deer damage to our revegetation plantings, we came across this large and strikingly patterned moth clinging to a tree guard. Our moth guru Peter Marriott, author/joint author of the wonderful series of books Moths of Victoria, kindly identified it as a female Magnificent Ghost Moth, Abantiades magnificus.

The Ghost Moth family, Hepialidae, includes some of the largest moths in Victoria, with females of one genus reaching up to 25 cm wingspan – the moth pictured at left would be about 16 cm across and the male a bit smaller at about 12 cm. The Ghost Moths are also known as Swift Moths or Rain Moths, as they often emerge from their pupal stage in the ground after rain. The larvae are commonly called Bardi grubs.
 
The Magnificent Ghost Moth pictured at right shows the male above and the female below. These images were reproduced with permission from Moths of Victoria (Part 6 Ghost Moth – Hepialidae and Allies) by Axel Kallies with Peter Marriott and Marilyn Hewish, published by the Entomological Society of Victoria 2015.

This was apparently the first sighting of this species in our area and the distribution map has now been altered slightly to include Strath Creek.

Sleek snake

March 23, 2020


 
The sleek snake pictured here was sunning itself beside our chimney the other day. It’s an Eastern Brown Snake, Pseudonaja textilis, but from the photo you could perhaps be excused, from a quick glance, for thinking it was another snake occurring naturally in Victoria: the White-lipped Snake, Drysdalia coronoides. That is until you knew the length of the snake, which was at least 1.5 metres, about 3 times the maximum length of the White-lipped.

And while you might tread rather casually around a White-lipped Snake which, although venomous, is not considered dangerous, you certainly would be a lot more circumspect around this Eastern Brown, which is not only dangerously venomous but lightning fast and quick to retaliate when provoked.

The lesson being, don’t provoke any snakes – just appreciate their sleek beauty from a safe distance (and be thankful for a camera’s zoom lens)!

Friendly falcon

March 18, 2020

We have been enjoying watching our resident Brown Falcon, Falco berigora, hunting at the back of our property where it remains quite unperturbed even under close observation.

The Brown Falcon is not a typical falcon in its methods of flying and feeding. Its flight is rather slow and heavy and it is often seen perched in the open on a fence post or dead tree branch. It is capable of hovering, somewhat clumsily, but its most common hunting method is to scan the ground from its perch and glide down quietly onto its prey, which it grabs in its talons. We have also watched one running and hopping around comically on the ground, chasing grasshoppers. Unlike some other falcons, it is less likely to pursue birds in the air, although it is certainly capable of it.

One of the most common and widespread of Australia’s raptors, the Brown Falcon is not always immediately identifiable due to its highly variable plumage, from a uniform dusky dark brown through mostly rufous, to brown above with whitish underparts, like the one pictured. The consistent giveaway for identifying this species is the facial markings, with a dark “tear drop” stripe below its eye and another dark patch on its pale cheek. It also helps to know that this is one of the noisiest raptors, with a characteristic cackling call in flight.
 

 
 
 
Not only is our falcon entertaining and quite tame, it is also performing a service by keeping some pests in check, hopefully including the occasional small rabbit!

Palp facts

March 16, 2020

Male Redback Spider

Spiders are remarkable creatures particularly the way they reproduce. In male spiders there is no internal connection between where the sperm is produced and the organ which delivers it to the female, the palp. Palps are two hairy appendages (they look like small legs) that protrude from the front of the spider. Among other things the palp acts as a siphon to collect the sperm from the male abdomen (or from a silk sac into which the sperm is deposited), and as a device to deposit that sperm into one or both female spermathecae (sperm storage containers), where the sperm can remain viable for up to two years.

I was reminded of this when I got a call last week from Michelle at Yea High School wanting to know whether I wanted to come over and photograph some Redback Spiders (Latrodectus hasseltii) outside a science block window. The sperm transferring process sounds pretty straight forward until you look at the size discrepancy between male and female redbacks (see photo below). The standard image of a black spider with a red hourglass marking is that of the female spider. Male redbacks (pictured above left) look entirely different and are way smaller.

Male (left), hidden female’s legs (top centre), egg sac (top right)


Male wrapping up prey

The redback spider provides one of the few examples in nature where the male actively participates in sexual cannibalism by offering himself to be eaten during mating. It is thought that this prolongs the mating process therefore increasing the quantity of sperm transferred. It is also thought to increase the chance of its sperm being used for reproduction (and not another male’s) by decreasing the probability that the female will mate again (no sex on a full stomach!) thereby ensuring its genetic line.

It sounds incredible but it’s not palp fiction.

It is busy in ant world

March 12, 2020
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I am not a rock roller. When looking for invertebrates in the landscape I am reluctant to turn over logs or rocks to find things to photograph. Even if I gently put the rock back where I found it I feel that I am destroying something’s home, let alone the fact that the revealed critters could be squashed. I was therefore a little distressed when moving a load of bricks to find  I had disturbed an ant colony, even more so when it was the ‘nursery’.

Uncovering an ant nursery creates a flurry of activity. Ant eggs, larvae and pupae required specific temperature and humidity conditions to develop properly. If those conditions are compromised i.e. someone moving the bricks, the young are quickly moved to an area with the correct conditions.

Eggs, larvae and pupae

The pictures reveal a whole community at work. Female (wingless) worker ants (black) are assisted by unmated (winged) queens and drones to move the young from one area to another. The photo above shows a nursery of ant pupae. Unlike butterfly pupae, ant pupae develop with the appendages (antennae, legs) free. The eyes are also evident. As the pupae near ‘hatching’ they turn from white to pale grey. Newly hatched ergates (young, female worker ants) are light grey in colour (see photo).

The initial role of a worker ant is to look after the young by providing food or transport. As workers mature the tasks change to more energetic jobs like digging and clearing the nest. In the ‘twilight’ of their lives worker ants are given the more hazardous jobs like defending the colony or foraging for food. If they get killed – well, they were old anyway!

I’m glad our local IGA is a safe place to shop.

 

The lost and lonely

March 8, 2020

Twitchers (fanatical birdwatchers) lead a life of quiet desperation, always on the look-out for a ‘lifer’ – a bird species they have never seen before. This explains the phenomenon late last year when hundreds of bird-watchers flocked (pardon the pun) to the Werribee Treatment Plant after the reported sighting of a single Paradise Duck (a species rarely if ever seen in Australia) bobbing among the thousands of birds down there. Sometimes however that special bird comes to you.

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Susan who lives just west of Yea last week reported a Magpie Goose (Anseranas semipalmata) on her property and wanted to know if it was unusual in this area. This bird is neither a magpie nor a goose. The binomial name is derived from the Latin anser meaning goose, anas meaning duck, semi meaning half and palmatus meaning webbed – a half-webbed goose-duck, half-webbed referring to its feet.

Today Magpie Geese inhabit wetlands of northern Australia and southern New Guinea where they feed on water-based and land-based plant matter. Their range once extended this far south but due to systematic destruction of wetland habitas for agricultural purposes the bird has long disappeared from this landscape. Attempts have been made to re-introduce populations of Magpie Geese in the south – at Bool Lagoon near Narracorte, S.A. and in the Serendip Wetlands near Lara. The sighted bird could be a member of one of those populations, though still far from home.

So to answer the question, these days the appearance of a Magpie Goose around here is highly unusual. As Geoff our local bird guru said ‘it looks lost and lonely’. It was only around for a day. On the bright side, it may have been scoping out new territory for its mates – Yea Wetlands maybe?

C’arn the blues

March 4, 2020
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A ‘blue’ on Purple Loosestrife

A  recent blog described the Hesperiidae family of small butterflies, commonly known as Skippers. They are a relatively unknown group of small, generally orange/brown butterflies. Another relatively unknown family of butterflies is Lycaenidae, the Blues and Coppers, also called the Gossamer-Winged Butterflies. They are the second largest group of butterflies comprising about 30% of known butterfly species. The majority of Lycaenids in Australia exist in tropical areas. There are less than a dozen species in Tasmania. Most commonly around here this family is represented by small blue/grey butterflies which are frequenting flowers at the moment (pictured left).

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Common Grass-blues (Zizina labradus) mating

Ants tending an Imperial Hairstreak caterpillar


The distributions of species are highly localised reflecting the spread of particular plants that the larvae feed on and the relationship many species have with specific ants. Many butterflies of the Lycaenidae family have a beneficial relationship with ants (click HERE to read the previous blog about the Imperial Hairstreak). The caterpillars and pupae have a gland which releases honeydew, a sugar-rich substance secreted by a number of insects including hemipterans such as psyllids and gumtree hoppers. The ants harvest this honeydew and in return offer the caterpillars protection from predators and parasites. In some species the caterpillars enter the ants nest to pupate and the emerging adult has to find its way to the surface.

Even though larger butterflies are more easily seen, a careful look at your flowering plants at the moment will give you ‘the blues’, in a nice way.