Thursday, April 26, 2012

Magical moths

We had recent visits by some of our rainforests most colourful moths. This is
Hypsidia erythropsalis, and oddly for such a conspicous species it does not have a common name.

While we humans marvel at such spectacular colouration, it is nature's way of saying beware. Some colourful species are distasteful to predators, sometimes even poisonous, while others are merely piggy-backing off the reputation. Whether or not this one can back up its claims I cannot say, but according to David Rentz's observations, this is one species that the birds do leave alone.

A close-up showing the colourful scales and hairs.

Another local brightly coloured moth is the Four o'clock Moth, Dysphania fenestrata. This species is actually diurnal and is often seen late in the day, hence its common name. We have observed the caterpillars feeding on plants around the house recently, and have seen several moths active. 

Four o'clock Moth, Dysphania fenestrata

Four o'clock Moth caterpillar

Monday, April 9, 2012

Hatchling predators

One of the many species we are breeding at the moment are the rainforest mantids, Hierodula majuscula. Females are very large and extremely robust, growing up to around 70mm in body length.

For the size of the mantis, this species actually produces a relatively modestly sized ootheca, but it is very tough and affords the eggs quite a bit of protection from opportunistic scavengers. Despite the hardness, many laid in the wild succumb to tiny parasitic wasps which deposit their own eggs deep inside the mantis ootheca using a hair-like ovipositor.

Most H.majuscula oothecae hatch around 40 days after the female produces them. Our most recent hatching consisted of over 100 tiny mantids. They emerge as vermiform (worm-like) larvae and moult almost immediately into 1st instar nymphs.

The vermiform larvae wriggle out of the ootheca and moult while suspended into the first instar nymph.

Like all mantids they are predatory and have a ravenous appetite. Some of our little hatchlings are now up to their 4th instar within their first month of life, and have made the dietary step up from drosophila fruit flies to small cockroaches.

A 3rd instar nymph posing for the camera

Friday, April 6, 2012


Two of the worlds most feared spiders; a Sydney Funnelweb (Atrax robustus) left, and a Brazilian Wandering Spider (Phoneutria reidyi) right.

Dangerous right? Perhaps. Nobody has died from Sydney Funnelweb bite since 1980, and deaths from Wandering Spiders are quite rare. Then again, think about this. Is a family car dangerous? No one runs screaming from the sight of them, yet in Australia over 1500 people die annually from motor vehicle accidents. Over 30,000 die each year in the US, and over a million people die globally. So where is the real danger? It’s not lurking in the shadows waiting to bite you, it’s sitting in plain sight in the driveway.

Thursday, April 5, 2012

Colourful hunters

This is Thomisus spectabilis, one of our local Crab spiders that has been relatively abundant lately. It is a flower dweller, and a white and yellow colour morph occur in our area.

Crab spiders belong to the family Thomisidae. These spiders are very diverse in appearance ranging from extremely colourful spiders, to drab cryptic species that resemble bark and lichens. They catch their prey by remaining completely still and waiting until prey strays within the reach of their powerful front limbs. Once grabbed, the prey is bitten and becomes immobile very quickly. Thomisids are able to tackle prey many times larger than themselves.

Sunday, April 1, 2012

Huge katydids dangerous around breeding time

We regularly have Palm Katydids Segestidea queenslandica in our garden, but recently their enormous relatives the Giant Palm Katydid Segestja cheqthadai have congregated in the palms around the property.

The huge females are ravenous during the breeding season, and due to this, large palm fronds are regularly falling. To be safe, we are making the kids wear their bike helmets while playing on the lawn.

The adult females usually remain high up in the palms, and only come to the ground to lay their eggs. Their ovipositing will certainly eliminate any need to aerate the lawn this year.

This female came down with the falling frond. Her powerful mandibles had cut through the woody stem with ease.