Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Monday, February 16, 2009

A new Moth for me - Epidesmia tricolor

Two weeks ago, while looking for Orchids in a wet patch of Melaleuca scrub, along a small creek line, I disturbed a moth which was very obvious when it flew. It had a yellow patch on its hind-wings. Unfortunately (for me) those yellow marks were not visible when it folded its wings down into this triangular position. Of course, if the marks were highly visible when settled, it would make the moth highly susceptible to predation. As it is, it still stands out prominently, despite its dark colours.

Here it is on a Sword Grass (Gahnia) leaf.
When it settled, it did so in a familiar triangular shape. But it had prominent white marks across the fore-wings. When you look at the image closely, you can see it has "palps" which protrude noticeably, giving it the appearance of having a long nose. It doesn't really. I was previously advised by Alan from Tasmania, with regard to a similar moth: "What you are seeing as being the antennae are actually porrect labial palpi or in simpler terms, forward pointing sensory organs that are part of the mouth."

Here, the moth is settled on a leaf of Coral Fern (Gleichenia dicarpa).
This moth settled on Sword Grass firstly, and then on some Coral Fern. Both these groups of plants were flanking the dense Melaleuca thicket, surrounded by wet, tall Eucalypt forest.

Fortunately, the marking on this Moth are sufficiently distinctive that I have been able to track it down in the Web resources. Its name is Epidesmia tricolor, within the OENOCHROMINAE, which themselves are within the GEOMETRIDAE family. This moth is reported as being found in the wet sclerophyll forests from south Queensland to Victoria. That fits with my record, from near the Belmore Falls Road.

Click on this image to see the head of this moth in full detail.
Its worth it.

I mentioned that this moth was highly visible, with yellow spots on its wings when it flew. That was the clinching diagnostic point. Here is a link to a specimen which shows what I mean.

I had previously seen another similarly shaped moth, in the same genus. That makes three related species which I have now photographed, but the other two were much plainer in colour. But the palps and the triangular shape of all three moths are consistent.

3 comments:

Duncan said...

Good one Denis, nice to have one in the daylight.

Mosura said...

What a beauty! Never seen one of those.

Denis Wilson said...

Hi Duncan and Mosura (welcome back, by the way).

Duncan made a good point, which had overlooked. The moth was active in the day. A previous Epidesmia I had found was also moving during the day, but in that case it was very dull and wet, so I figured it was confused.
This one was out and about on a clear day.

Mosura, I checked your site first, but could not find any reference to it - now I know why.

Cheers
Denis