2018 October 8

   Thanksgiving Day is perhaps a good day for me to give thanks to all the many contributors to this site, to the experts who helped so willingly with the identifications, and to whomever or whatever you believe in that gave us all these wonderful invertebrate creatures to marvel at.

   The butterfly season is probably now really over (but keep your eyes open – you never know), but there are still lots of invertebrates around, and this site will remain open for contributions.

   Libby Avis spotted a geometrid caterpillar on Pearly Everlasting on Mount Arrowsmith on October 6.   It matches the colour of the flowers perfectly.  It is almost certainly a pug (Eupithecia sp.), but I don’t think we can go beyond that.  

Eupithecia sp. (Lep.: Geometridae)  Libby Avis

   Jeremy Tatum writes:  This American Tissue Moth was at my Saanich apartment this morning:

American Tissue Moth Triphosa haesitata (Lep.: Geometridae)  Jeremy Tatum

   Rosemary Jorna writes:  This beetle was on the trail  near Camp Thunderbird  on October 6.  Thanks to Scott Gilmore for identifying it as Scaphinotus angusticollis.

Scaphinotus angusticollis (Col.: Carabidae)  Rosemary Jorna

         Jeremy Tatum writes:  In the May 28 evening Invert Alert, we posted pictures of a snakefly photographed by Andrew Simon on Galiano Island.  We had to struggle with the identification of an insect from this not-very-familiar Order.  Now we are grateful to Chris Ratzlaff of the Spencer Entomology Museum, who has identified it as Agulla assimilis.  We have added this label to the May 28 evening entry, together with some remarks by Dr Ratzlaff.

2018 October 7

   Jeremy Tatum writes:   Yesterday I saw my first Banded Woolly Bear (caterpillar of the Isabella Tiger Moth) of the season at McIntyre reservoir.   There should be lots of them in the next couple of weeks.  Panama Flats is a good spot for them.  Photograph, someone?

   This moth was on my bedroom carpet this morning.  It was in good health, and it flew strongly out of the window after posing for its portrait.

Tetracis jubararia (Lep.: Geometridae)   Jeremy Tatum

   Now, three dragonflies – thanks to Rob Cannings for the identifications. 

   This Common Whitetail (not particularly common!) was photographed by Jody Wells in North Saanich on October 8.

Male Common Whitetail Plathemis lydia  (Odo.: Libellulidae)   Jody Wells

             Next is a Saffron-winged Meadowhawk photographed by Rosemay Jorna at Glintz Lake on October 6

Male Saffron-winged Meadowhawk  Sympetrum costiferum (Odo.: Libellulidae)

  Rosemary Jorna

   The meadowhawks can be tricky, and Rob suggests leaving the next one, photographed by Jody at Rocky Point on October 4,  as Sympetrum sp.

Meadowhawk  Sympetrum sp. (Odo.: Libellulidae)  Jody Wells

   The October Butterfly Walk didn’t take place today.  Jeremy Tatum writes that although he said he’d be on Mount Tolmie rain or shine, it was roaring with pain at 1:00 pm, so he stayed indoors with a good book.  Apologies to anyone who turned up and found no one there!

2018 October 6

   Jeremy Tatum writes:   I saw about four Cabbage Whites over or near the cabbage fields at Island View Road today.

   Here is a picture of a moth that arose from a caterpillar found on Gumweed during the VNHS Butterfly Walk on September 2.   I released it today near to where the caterpillar was found at Island View Beach.  See Val’s photograph of the caterpillar on the September 2 evening posting.

Heliothis phloxiphaga Lep.: Noctuidae)  Jeremy Tatum

2018 October 5

   The Monthly Butterfly Walk is scheduled for Sunday, October  7.   The weather forecast is not great. However, being optimists, we have not cancelled the walk and Jeremy Tatum will be at the Mount Tolmie summit at 1 p.m., rain or shine.  You never know, the sun may shine long enough for a butterfly or two to appear.  If there is steady rain, however, we are unlikely to find anything.  Although  butterflies have been scarce in September, there have been some spectacular rarities, such as Monarch, American Lady, Mourning Cloak and California Tortoiseshell.  And an Orange Sulphur is not unknown at this time of year.

2018 October 4

   Jeremy Tatum writes:  Now that this site is not quite as busy as it was in mid-summer, here’s a leisurely opportunity to think about tiger swallowtail identification.  It should be easy:  The background colour of the Western Tiger Swallowtail is yellow.  That of the Pale Tiger Swallowtail is white.   Right?   My problem is that sometimes I can’t be sure whether the colour I’m seeing in yellow or white.  Perhaps the yellow of a Western has become faded with time, or something like that.

  Here, then, are two additional clues:

Western Tiger Swallowtail

Western Tiger Swallowtail

1.   The yellow and black tiger stripes at the leading edge of the forewing are approximately equal in width.
2.   The crescent-shaped spot at the base of the long hindwing tail is yellow.

Pale Tiger Swallowtail

Pale Tiger Swallowtail

   1.  The black tiger stripes at the leading edge of the forewing are broader than the white stripes.

   2.  The crescent-shaped spot at the base of the long hindwing tail is mostly orange (with maybe a little white at its tip).  (Thanks to Mike Yip, who drew my attention to this feature.

   What brought this up is that I was recently perusing some past Invert Alerts, when I came across the following picture by Kirsten Mills, May 27, which I had identified and labelled as a Western Tiger Swallowtail.

Kirsten’s photograph

   Well, maybe the background colour looks slightly yellowish, but from the above criteria you can see clearly that I had misidentified it (apologies to Kirsten!), and  it is in fact a Pale Tiger Swallowtail.  I have now relabelled it as such.

   I do not know of any feature by which I can distinguish between the caterpillars of the two species, other than foodplant, which is usually willow for the Western and alder for the Pale.

  Do they ever hybridize?  Are there some individuals that we cannot identify confidently, even if we try to use the above two features?   Let’s keep a look-out next summer.

   Of course there are other species of tiger swallowtail, such as Canadian and Eastern Tiger Swallowtails, and at the moment I don’t know how to identify them reliably.  Presumably they don’t occur on Vancouver Island – but who knows?  Let’s keep our eyes open!

  Another complication:  As with most other organisms, there have been name changes over the years.  I am not sure why some recent authors have chosen to omit the word “Tiger” from Pale Tiger Swallowtail, and call it just the Pale Swallowtail.  Maybe because real tigers aren’t white?   But the Pale one is obviously one of the tiger swallowtail group (subgenus Pterourus); the omission of “Tiger” somehow suggests that it should be set apart and doesn’t belong to this group.  That is why I usually prefer to retain the “Tiger”.