Lacewings and Ant-lions

Lovely to look at, but vicious to know

Lacewings and Ant-lions are predators, particularly in their larval stage. The better known ant-lion larvae live in dry sandy soils waiting for small invertebrates like ants to come by and fall into a depression and then into their massive grasping jaws. They are thus held whilst the ant-lion pierces their body with a tube, to then suck them dry. The world of insects can be a very grizzly place.

Other lacewing larvae tend to be more free moving, some patrolling the undersides of leaves in search of aphids and scale, whilst others live in rotting wood, disguising themselves with a covering of leaf/wood litter. Yet others live a semi-aquatic life on the edges of streams, feeding on aquatic invertebrates.

Both lacewing and ant-lions have wide Australian distribution, however the former are more common in the wetter eastern States, whilst the later are more common in the drier interior and western regions. As for species numbers, there are a lot of them. To give an idea, in the lacewing Order Neuroptera there are 6 superfamilies that are divided into 14 families, which in turn have a considerable number of genera and vastly more species. So yes, that little old ant-lion you once saw is only one of many species.

The well known ant-lion from the superfamily Myrmeleontoidea and the family Myrmeleontidae come in several guises, but basically they have big jaws and a body with maybe some legs for mobility. Around me is one that lives in the top couple of centimetres of sand, but instead of remaining stationary like most ant-lions, this one swims through the sand leaving snail-like trails.

To swim, it moves backwards through the sand and is propelled by a couple of paddle-like legs, one on each side of the body.

Although no threat to Olympic swimmers, it can disappear very quickly if exposed.

Ant-lion from the Myrmeleontidae family

The adults typically have four lacey wings comprised of interconnecting veins, the arrangement of which are distinctive to various groups and are an important aid to identification. The one below seems to be saying. Look at me! Look at me!

Another method to identify these insects is by their antennae, note with this species how short they are and thickened towards the tip. This places them in the family Myrmeleontidae, the Ant-lion group.

Ant-lion from the Myrmeleontidae family

The adult lacewings with their large eyes, reflect torch light and are therefore very easy to spot at night. So another reason to go spotlighting for invertebrates. You never know what you might find.

With so many Lacewing/Ant-lion species in Australia, I had to include another to illustrate some of the more obvious differences between them. Many will be familiar with the distinctively different green toned lacewings, or the bizarre mantid type with grasping limbs, but have a look at the one below. To an entomologist the differences are crystal-clear, but if you are like me, it takes a little study to see what they are.

Lacewing from the Nymphidae family

Did you spot the differences? For a start the wing reticulation is quite different, but most noticeable are the antennae, these are much longer than the Myrmeleontidae species above, plus they are not thickened at the tips. This places this lacewing into the family Nymphidae. Its larvae is probably one of those non-descript, big jawed insects that wander around on plants looking for small slow moving prey.

Before disturbing dry areas under eves or overhangs, check for inverted cone shaped depressions, as these are the places you will find your ant-lions, which in turn grow into the pretty lacewings. These are good predators by the way, and are helping to keep garden pests under control, so don't forget to leave a little habitat for them.

Icerya purchasi, an Aussie sap-sucker

Icerya purchasi, the Cottony Cushion Scale prefers Acacias (Wattles).

Scale insects belong to the large and varied order Hemiptera, which include the bugs, such as cicadas, leafhoppers, stink/shield bugs, aquatic bugs, lerps, gall insects, scale, aphids and mealybugs. However Icerya purchasi, the Cottony Cushion Scale (also known as the Australian mealybug and Fluted scale) belong to the family Margarodidae that includes the mealybugs. So what is a scale and what is a mealybug?

Well a mealybug is a scale insect as they all secrete a white waxy layer in which to live, except with mealybugs the adults have a powdery looking exterior and hence the term mealybug. Some mealybugs like the Cottony Cushion Scale also have a cottony appearance.

With the Cottony Cushion Scale, Icerya purchasi, the 5-10 mm fluted part at the rear of the insect in not the body, but masses of eggs contained within tubes that have grown from the mealybug's stomach. The actual bug is the smaller oval, colored portion with the legs.

Cottony Cushion Scale, Icerya purchasi

During the early stages the young mealybugs move around seeking out suitable places to feed, ants will often carry them to various locations in order to milk them of a sweet fluid that is excreted from fine waxy tubes at their rear. At this stage they are known as crawlers or nymphs and are tiny, initially being around 0.5 mm. Once in a suitable spot, the nymph will extrude a waxy covering (the scale) and begin to feed on the sap of the host plant, which in Australia is usually an Acacia.

As I do not possess a special macro lens, I photographed this juvenile through a microscope.

The much smaller male mealybugs are rare as the female does not need them in order to produce fertile eggs, as she is a hermaphrodite, meaning that he/she/it is both male and female. The males when produced are unlike the females and develop wings in order to find the ladies, but when they emerge from a their small waxy shell they have no mouth parts and exist only to mate. Naturally their adult life span is short, but presumably a happy time.

The adult females after several moults produce their egg-sacs, usually depositing the eggs on the undersides of leaves or along small stems. As each female can produce up to a thousand eggs, this can take quite some time and they are never in a hurry.

These two ladies look like they are making good time, but you could return a day or two later and see little or no movement of either. However they can get a move on when they want to.

The photo below is not a Cushion Scale, but a more conventional scale that is mobile in its waxy (scale) covering. It was most indignant when I plucked its leaf and seemed to be saying. Oi, what do you think you're doing?

The Cottony Cushion Scale, Icerya purchasi was the subject of the first successful biological control using an introduced predator. This scale is native to Australia, but has spread to many parts of the globe where it has become a serious pest to many orchard and ornamental plants. In 1868 (after an accidental introduction) it was discovered in California, where it soon infested their citrus trees. It proved to be not only difficult to control but also very expensive and time consuming.

As there were no natural predators of the Cottony Cushion Scale in the USA, the search began in Australia where it was not a serious pest and it was discovered that the Australian Ladybird Rodolia (Novius) cardinalis fed on them. The ladybird was soon introduced to America, Europe and North Africa where the Cushion Scale was proving to be so destructive and the infestations were reduced to manageable proportions.

Helea and a Sympetes species from the SE of WA

Pie-dish Beetles are not only very unusual, but can be steaming hot too!

The genera Helea, Pterohelaeus and Sympetes (commonly known as Pie-dish Beetles), are endemic to Australia (Sympetes only in WA) and belong to the family Tenebrionidae. There are over 50 species and although widespread, they tend to favour the drier regions. The Helea species are distinguished from Pterohelaeus and Sympetes by having a wider flange with the top section meeting or overlapping above the head.

A very hairy backed Helea perforata from the Esperance region of WA.

All Helea and some Pterohelaeus and Sympetes beetles are wingless and their elytra (hardened forewings that form the back of the beetle) are fused together. As their breathing system is below the elytra, a micro environment is created to retain moisture and enable easier breathing, both an advantage in a dry climate. Anyway, they are nocturnal and ground dwelling, but by day usually rest under leaf-litter, rocks, logs or loose bark. They will often return to the same resting-place each day.

The hardened elytra and flange provide protection from predators, as they can resist penetration from spider fangs or scorpion stingers. They can also use the flange to flatten themselves on the ground to avoid being turned over or attacked from below.

A mating hairy-backed couple not bothered by extended flanges. Note how the flanges overlap above the head.

 

Pie-dish Beetles, Helea perforata

Most of the Esperance pie-dish beetles are between 1.5 - 2 cm in length and are not hairy; in fact some are quite smooth and shiny like Sympetes testudineus, although the one photographed below could be the same as the mealy species further down, but older with the flour-like substance eroded away.

 

The Sympetes pie-dish beetle below is having a nibble on a rolled oat, it has a covering of fine flour-like grains on the elytra, but take note of the missing flange section above the head, this is the most obvious distinguishing feature between it and the Helea pie-dish beetles.

The single raised portion along the back, is common to these beetles (all genera), being the fused portion of the elytra, however others can have additional ribs on either side.

 

Pie-dish Beetle, Sympetes species

The oat munching Sympetes Pie-dish Beetle in profile. Note there is very little for any predator to grasp. However all adult pie-dish beetles are very inoffensive, being vegetarian and normally only feeding on dead and decaying plant material.

Note with this mating pair of Helea consularis (flange meeting above the head) the additional ribs and their pronounced raised flange. These flanges are not raised to enable mating but are a feature of this species.

I stopped filming after this shot as I was beginning to suspect that I was becoming involved in a hot pie-dish porno movie.

So next time you spot a pie-dish beetle wondering around at night, check out its features to see how many types you have. You might be surprised!

Updated March 2013. 

The Crane Fly from the subfamily Tipulinae

Crane Flies are flies, not big mosquitoes or daddy-long-leg spiders

They belong to the family Tipulidae, which interestingly has more species than any other fly family in Australia. This family belongs to the suborder Nematocera, which does include Mosquitoes, Midges and Sand Flies. However the Crane Fly is quite harmless, it neither bites, stings or sucks blood, in fact many do not eat at all, being only able to drink, consequently they are very short lived and mainly exist to establish the next generation.

With legs like these, they can't even run fast, particularly when some are easily mislaid.

Crane Fly from the family Tipulidae

Most Crane Flies have an aquatic larval stage and generally prefer moist shady environments, so they are far more common in the near east coastal areas from Tasmania to north Queensland. However we do have over thirty WA species from several genera, whereas in the east they have many times that number. Besides those that prefer aquatic environment, there are also some that breed in moist soils, compost and rotting vegetation. These larvae of these will feed on the decomposing vegetation and/or small invertebrates.

With such long legs, some positions are out of the question.

Unless you look closely, you would think that this fly has a large head and a long proboscis, but on closer inspection it is the thorax that is large and the proboscis looking part, the real head. Examination of the antennae, this species has unbranched tips, which taxonomically places it in the subfamily Tipulinae. Unfortunately I cannot id it to genus let alone species level, as these details are only published in specialist journals that I do not have access.

Some flies do have nasty irritating habits and spread disease, but Crane Flies are one of the good guys.

Australian Cockroaches can be strikingly colourful and highly sociable

Several southern WA Cockroach species, from the families Blattidae and Blaberidae

Australian indigenous cockroaches seldom enter houses, this is unlike the introduced varieties that fly/crawl into your home to become irritating and persistent pests. So now please consider our native species, because they can be very beautiful and highly social animals, mainly living on leaf detritus, rotting wood, flowers and nectar. Many do not have wings, so seldom move far from their preferred habitat and usually live under leaf litter, in burrows, in/under rotting logs and under the bark of trees. Most are nocturnal, but some can be found during the day on various vegetation types.

Have a look at this one; it would have to be amongst the most colourful of any insect. Its name is Polyzosteria mitchelli, but is generally known (along with many other species) as a Bush Cockroach from the family Blattidae. It grows to around 5 cm in length.

Bush Cockroach, Polyzosteria mitchelli

It came.

It saw.

Then left (don't you just love those blue socks).

This one is carrying a hard egg case, called an ootheca, which can contain between 12 to 40 eggs (depending on species). The ootheca is slowly extruded by the female and eggs neatly placed within, it will eventually be deposited in a safe place for the young to develop (which with most cockroaches) will be left to fend for themselves.

Not all species of the Blattidae family are highly colored; one common Platyzosteria species is totally black. This one is also carrying an ootheca.

This Platyzosteria species is seldom more than 3 cm in length and can be found at night, quite high in trees where it seeks out flowers on which it feeds. It is also found on the ground and probably is a common prey species for mammals, frogs, reptiles, arachnids and night birds. In defence, many species including this one, will raise up their rear and release a foul smelling concoction to deter any predator with a sensitive nose.

Being completely black, it can play the part of Darth Vader very convincingly.

A Cockroaches life however is not all fun and games, as they have parasites that can be fatal, one of these is the Gordian worm belonging to phylum, Nematomorpha. The adult worms intend leaving their host near water so they can breed and provide habitat for their aquatic young. However, as can be seen with this one, the host is not always cooperative and the worm also dies. (My thanks to the Australian Museum for this information)

This next species (also from the family Blattidae) can easily be confused with the black variety above (similar looking cockroach species can only be distinguished by their genitalia). However, this species was reasonable distinctive, being a dark bronze in colour, slightly smaller, with shorter leg spines and a pale horseshoe shaped area along the upper shield edge.

This pair are intent on making a large ootheca full of viable eggs. Note the small one (probably the male) compared to the much larger female. Dimorphism and other differences are not unusual with cockroaches and some males and females have in the past been described as different species.

This lady having made her ootheca, is looking for a good spot to place it. Note how fat these animals are, quite unlike the introduced cockroaches, which tend to be flat with both sexes winged.

Yet another cockroach from the Blattidae (this family by the way, is the largest of the five Australian cockroach families, having as many species as the other four families put together). This one is a Drymaplaneta species, or a Bark Cockroach and has a prominent creamy/white horseshoe marking on the shield.

Although having no wings, it is a very good climber (here on glass).

This is a juvenile Blattodea species typically feeding from a Banksia speciosa flower.

Now for a different family! It includes the largest (to 7 cm) and most bulky cockroach in the world and lives here in north Queensland, it is a member of the Blaberidae family. However, this Esperance WA species is much smaller, being less than half that size, but it has the characteristic broad, bulky shape and short legs. These are social animals and raise their young in underground chambers, or under leaf litter, in rotten logs, or dead Grasstrees (Xanthorrhoea sp.) and because of their shape, are commonly known as Trilobite Roaches. The males of these Calolampra species are usually winged, yet they all live together in communities with the females and the young, apparently communicating with each other by scent.

This group with the large, more heavily armoured outer shield, which combined with shorter legs (ideal for digging) are a much slower moving cockroach than most people are familiar with. They probably move around less too, so are not commonly seen unless you happen to be near their nest.

And who could resist this shy modest Trilobite Roach?

So remember, all roaches, ain't just roaches, particularly when they're native roaches.