Friday 21 May 2010

The Nameless

This was a nice surprise last night - the first Noctuid I have seen in almost a month. A sort of Clint Eastwood among the Pinions, seen here enjoying a drink from a damp salmonberry leaf after its temporary confinement while I attempted to name it. Like our Lithophane species it flies late in the year, hibernates, and flies again in spring. (Of 65 species in this Holarctic genus half a dozen are found in the UK and 44 in North America according to Powell and Opler).

Lithophane innominata - The Nameless Pinion - 19/5/2010 Lake Forest Park, attracted to houselights


Two other moths came and must also be nameless for now. One is another Hydriomena sp. (or possibly the same as below). The smaller (it has a wingspan of about 20mm), plainer species shown here has, I think, visited at least 3 times before this month. Frustratingly, I do not know what it is. Possibly a species of Venusia...

Thursday 20 May 2010

Sagebrush Steppe - brown wave among clouds of blues

We ventured east of the Cascade mountains again on Sunday to Umtanum Creek, Kittitas county. This area is technically rain shadow desert environment and now is a good time to visit - before it gets too hot and the vegetation is not yet parched. It was still pretty hot on Sunday. Photographed hundreds of plants, many in flower, saw my first Western Bluebird. Many rattlesnakes. Just the one moth.


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Sagebrush steppe or desert habitat in the valley of the Umtanum Creek, west of Yakima Canyon. Prairie Lupins and Balsamroot (the yellow flower) are in bloom.

The Umtanum Creek (left) is mosaiked with sagebrush steppe & rocky grassland around the lower talus slopes of the valley, woody riparian scrub and groves of aspen and cottonwood trees on its floor.
In spite of the abundance of unseen before wildlife was pleased to find a moth on this trip. Clouds of blues (I think these are mostly Boisduval's Blue Plebejus icarioides) were congregating around the creek (rushing, presumably from high altitude snow-melt) and sipping moisture from the small patches of damp silt at its margins (left, the photo also shows some rather bedraggled Equisetum arvense but Equisetum laevigatum was also present - this is the smooth stalked scouring rush - which seems a somewhat oxymoronic name). The mesic zone in this landscape is very narrow and walking along the creek feels like visiting a ribbon oasis in a wilderness of dry basalt rock and sagebrush. We also saw a number of Checkerspots and a yellowish bird-size butterfly which I couldn't get close enough to photograph or identify. The small moth, which was also sipping water from the silt, is the Dark-ribboned Wave (Leptostales rubromarginaria) - the only western member of a Geometrid genus - endemic to the new world - of about 55 species.

Wednesday 12 May 2010

More spring Geometrids

Triphosa haesitata - Tissue Moth - 8/5/2010 Lake Forest Park

Hydriomena sp. - 8/5/2010 Lake Forest Park

Xanthorhoe defensaria - 11/5/2010 Lake Forest Park

Still little moth activity over the last few days. The odd spring flying geometrid settles by the outside lights, and not every night. Still, they are not all easy to identify... The top one is a Tissue Moth, which is a congener of the British 'Tissue' (Triphosa dubitata). It is a very handsome insect not really done justice by this photo. They fly in summer, overwinter as adults and fly again in spring. I recorded this species here on 21st August when last in the States. Like dubitata, the larvae feed on Rhamnaceae.
 
Next is a species of Highflyer (Hydriomena) but I have not been able to determine species. Possibly H. irata but there are 56 North American species plus an estimated 10 undescribed in the West (as opposed to 3 in the U.K.) There are a few photographs online of specimens with almost identical markings but the captions all refer to Hydriomena sp. Pictures of named species in the books and websites I see look different.
 
Third is Xanthorhoe defensaria. Probably. Xanthorhoe is another fairly speciose genus with many similar species.

Friday 7 May 2010

Still cold... dusting of moss green scales on mottled grey carpet

Cladara sp. - Lake Forest Park 7/5/2010

Yesterday and today the sun has broken through the cloud, quite warm in the afternoons and a few more butterflies about. Still very cold at night, but this morning, one 'new' species to admire by the outside lights. I believe it is Cladara limitaria - the Mottled Gray Carpet but it may be another of the three species in this American genus.

Wednesday 5 May 2010

And one of last year's Boarmiinids...

Brown-lined Looper - Neoalcis californiaria (Geometridae) - Lake Forest Park 31/8/2009, attracted to outside lights.

Another very chilly night and no moths except a Sabulodes aegrotata which we found the night before last and has been resting on the window frame since. Catching up with photographs taken in the summer, this is of the same Boarmiini tribe as the two below. Like Melanolophia the larvae feed on Douglas Fir and various other conifers. On that topic, the Douglas Fir branch I had been keeping in the garden with Silver-Spotted Tiger larvae feeding on it has today disappeared - no doubt 'tidied away' by someone.

Tuesday 4 May 2010

Disentangling spring Geometrids

Small Engrailed - Ectropis crepuscularia (Geometridae), Lake Forest Park 28/4/2010
Western Carpet or Green-striped Forest Looper - Melanolophia imitata (Geometridae), Lake Forest Park 1/5/2010
 
After initial perplexity have separated and tentatively named these two similar moths (both attracted to outside house lights) as above with the help of some good internet resources. The distinguishing features are that the Wester Carpet has a small blackish discal spot on the forewing, a more prominently scalloped post-median line - especially at the trailing edge and a sub-terminal line consisting of black spots (in Ectropis the ST line is better likened to a row of tooth marks). Both species are rather variable but the darkest wing marking on Ectropis crepuscularia is said to be the blackish area along the post-median line near the centre of the forewing. May yet revise this identification if I get to see more individuals.

Thanks to these websites for an excellent set of photographs for comparison and useful notes on identifying marks:
Moth Photographers Group (particularly John Davis's Moths of the Pacific Northwest which is proving indispensable)

Saturday 1 May 2010

Identifying North American moths - there are rather a lot

Have managed to borrow a moth book - the moth book in fact, for the western states of the USA - and will be using it to help name and inform my moth observations from this and previous visits to the U.S.A.

Moths of Western North America by Jerry A. Powell and Paul A. Opler, University of California Press, 2009

It is a very fine and serious hardback book, large format with 370 pages of text and 64 colour photographic plates showing traditionally spread specimens. There are about 2500 species illustrated and described. Prior to the arrival of this work last year the published information available on Western North American moths was either obscure and scattered or else superficial.

However, the diversity of the region's lepidoptera is so great - this work is not a compendium of the fauna or a guide to it but a detailed overview representing about 25% of the species in each of the native families (all of which are treated). It comes as a bit of a shock for someone from a small 'biologically depauperate' European island to think that this hefty and definitive looking book therefore will not cover, say, 75% of the Noctuid species flying around out there (in fact it is likely to describe most of what a casual observer will encounter because the species were selected based on being widespread, well known, more easily identifiable or of some other notable interest). The authors estimate that there are about 8000 named species of moth in the western states and provinces and at least another 3000 species for which specimens have been collected but not yet described. Worldwide there are 160,000 - 180,000 named species in the Lepidoptera and the real total could easily be more than double this.

Makes a dilettante moth-er think, but since arriving here the nights have mostly been chilly and there appear to be very few moths flying yet.

Behrensia conchiformis (Noctuidae) - Lake Forest Park 25/4/2010 found by outside light. Its local foodplant is likely to be Snowberry (Symphoricarpos albus) which I have now seen for the first time as part of a natural plant community. I wonder what, if any, insects feed on the extensive gamebird cover and garden populations of this plant back home.























Larva of Silver-Spotted Tiger Moth - Lophocampa argentata (Arctiidae) - Lake Forest Park 25/4/2010 found on fallen Douglas Fir (the foodplant) branch. Other individuals also seen on wall, apparently attracted to light, and Vine Maple (Acer circinatum) foliage, presumably dropped from fir canopy above.


This is Xanthorhoe labradorensis (Geometridae) - which I suppose would be the 'Labrador Carpet', Lake Forest Park - attracted to outside light 26/4/2010. I must say, it looks a lot like a European Flame Carpet to me, and apparently some authorities have indeed classed it as a subsp. of X. designata.


Sabulodes aegrotata (Geometridae) - Omnivorous Looper, Lake Forest Park, 24/4/2010, perched on outside wall by light for at least 3 days but has now gone.

Wallace Falls State Park, Snohomish County

Wind, rain, low temperatures and no moths at the house again, last night, but the book has pinned down this photograph taken earlier in the week.

It is one of three described species of the genus Enchoria (Geometridae) which is endemic to the Pacific Coast. A day flying species from March to May - we saw it circling a sunlit gap in the Western Hemlock-Douglas Fir canopy, by Wallace River, and followed it to rest on a salmonberry leaf.

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Enchoria lacteata - Wallace Falls State Park 25/4/2010