Help identify moth.

It's not their fault they don't have feathers! Doesn't make them any less interesting. And just like the birds, it's good to know what species are about locally at any given time.

There's expertise within the club and beyond on most aspects of our local fauna. Let's tap into it.
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sburke
Posts: 158
Joined: Wed Mar 11, 2009 10:30 am
Location: Townsville Region

Help identify moth.

Post by sburke »

On an early morning run last week I found a really large moth (still alive) under a light in the carpark of the St Andrews Hospital. It's wingspan was about 7 inches, it was primarily a light brown colour with a dark eye on the lower part of each wing. It reminded me a little of a hercules Moth but the lower wings didn't extend as far past the end of the abdomen as a Hercules.

As a side issue I dug up a big, black, angry Funnel-web Spider in my garden on the weekend. It was very vicious and active.
Rod Hobson
Posts: 509
Joined: Thu Jan 19, 2006 8:03 am

Post by Rod Hobson »

Dear Steve,

Sounds like one of the gum moths, most probably the Emperor Gum Moth (Opodiphthera eucalypti); a common SEQ species - wingspan of 95-120 mm.

There are two local funnel-webs; both only found in the wetter eastern side of the city. The most common is the Toowoomba Funnel-web (Hadronyche infensa) with the rarer of the two being the Tree Funnel-web (H. formidabilis). Your spider was most probably a female infensa considering the situation in which it was found. Where in Toowoomba was this spider located?

Regards,
Rod Hobson
Last edited by Rod Hobson on Mon Mar 01, 2010 6:19 am, edited 3 times in total.
sburke
Posts: 158
Joined: Wed Mar 11, 2009 10:30 am
Location: Townsville Region

Post by sburke »

Thanks Rod. Yes that definitely was the moth. A male. The "infensa" funnel-web was found at Pioneer St across the road from St Andrews Hospital. Handy if i ever get bitten :)
Rod Hobson
Posts: 509
Joined: Thu Jan 19, 2006 8:03 am

More on Funnel-webs

Post by Rod Hobson »

Steve,

I think that your spider was most probably one of the trapdoors rather than a funnel-web considering the location in which it was found, probably the Toowoomba Brown Trapdoor (Euoplos sp.). Saint Andrew's Hospital is in the drierer western part of Toowoomba and both local species of funnel-web are restricted to the wetter eastern parts of the city and range escarpment. The local funnel-webs are the quite common Toowoomba Funnel-web (Hadronyche infensa), which is more widely distributed than its common name suggests and the less common Tree Funnel-web (Hadronyche formidabilis). Trapdoors are generally common around Toowoomba and are represented locally by several species. The Toowoomba Brown Trapdoor is particulary common on the western side of the city. And not all trapdoors have the conspicuous lid to their burrows that give these spiders their colloquial name (although the Toowoomba Brown Trapdoor does).

Both trapdoors and funnel-webs rear up quite spectacularly when aggravated, a feature that is conspicuous of the primative group of spiders (the Mygalorphae) to which both belong. The fangs in these spiders strike (stab) downwards and this rearing motion is necessary for the spider to deliver its bite. Most other spiders (the moderns, the Araneomorphae) have a pincher-like biting mechanism so they don't need to rear to deliver their bite.

The best way to distinguish a trapdoor from a funnel-web (male and female) is by the relative proportions of their spinnerets - the web-producing organ at the rear of the abdomen. In funnel-webs the terminal segment of the spinneret is longer than wide and vice versa in trapdoors. Females of both types are hard to distinguish but are rarely encountered, as they spend most of the time in their burrows. Males of funnel-webs are highly active especially in the hotter, wetter months and are often encountered. Toowoomba Brown Trapdoor males are particulary active around Toowoomba at present (April) and the species is well known to be an active autumn wanderer. Males of these spiders are not as difficult to tell apart, as are the females. The males in some species of funnel-webs have a tibial spur on the inside of their second pair of legs however this is absent in the Toowoomba Funnel-web and reduced to a knob in the Tree Funnel-web. On male trapdoors this spur is on their first pair of legs and quite conspicuous when they rear. The palps, the male sexual organs, of trapdoors are clubbed at their ends; it looks as if the spider is wearing boxing gloves whereas those of funnel-webs taper towards their extremeties. The palps jut forward just in front of the male's front legs.

So, in conclusion, big glossy and rearing spiders from the drier parts of Toowoomba are most likely trap-doors whilst from the wetter parts they can be either.

Regards,
Rod Hobson
Last edited by Rod Hobson on Sat Jul 04, 2009 11:49 am, edited 7 times in total.
sburke
Posts: 158
Joined: Wed Mar 11, 2009 10:30 am
Location: Townsville Region

Post by sburke »

Thanks Rod. Is the Toowoomba Brown Trapdoor always brown? Because the spider I found (which was located on the southern moister side of the house) was definitely black with white leg joints and I have spoken to my neighbours who have been in their house for over 50 years (before St Andrews was built) and they have said that over the years they have had both trapdoors and funnel-webs in our area. Admittedly numbers have dropped since the all the rocks, trees and scrub was cleared for the hospital. I have compared photo's on the net of the two species and now that I have seen a photo of the Brown Trapdoor I am certain the spider I found was a funnel-web. If I catch another one I will keep it for proper identification.
Rod Hobson
Posts: 509
Joined: Thu Jan 19, 2006 8:03 am

Other possibilities

Post by Rod Hobson »

Steve,

The male of the Brown Trapdoor is very dark and could be construed as being black at a glance. I'm not sure, as to the expertise of your neighbour regarding spiders but I'd take a layman's opinion regarding this matter with a 'grain of salt' unless the spider in question has been identified by a professional arachnologist. Of course it's possible that funnel-webs do exist in the area concerned but have remained unrecorded there. Have you considered other mygales that have a very similar appearance to the funnel-webs such as the False Funnel-webs (Aname spp.), male and female Mouse Spiders Missulena bradleyi, M. dipsaca and the female Mouse Spider M. occatoria? All these are quite black and very similar to funnel-webs. The only way to separate a funnel-web from a trapdoor, or other mygales does depend on an intimate inspection of tibial spurs, palp shape, condition of spinnerets etc., as I detailed in my previous note. Casual observation is not trustworthy. I guess we won't know if funnel-webs are present in the St. Andrew's area or not until we get a specimen. It'd be good if they were, as I'm very fond of these spiders, a passion unshared by 99.9% of the population.

Regards,
Rod Hobson
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