Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Photo#710682
Samea ecclesialis - Samea castellalis

Samea ecclesialis - Samea castellalis
Henderson, Chester County, Tennessee, USA
September 3, 2012
Thanks to JD Roberts for providing the following information to help separate Samea ecclesialis and Samea multiplicalis.

"The simplest way to distinguish these two species is the forewing fringe and the pale spot in the FW median area near the inner margin.

1. Samea ecclesialis always has a dark "spike" in the FW fringe that creates a darkened arrow-like shape at the FW tornus.

2. This is topped by a pale section of fringe (going toward the apex)...

3. ...followed by a conspicuous darkened area of the fringe midway along the margin.

4. Now the pale spot in the median area can be a little more difficult, but generally in ecclesialis, the pale spot is evenly divided by the vertical black line, whereas in multiplicalis, the black line is more to the distal side, dividing the pale median spot unevenly with the large portion basally, and the smaller portion distally.

...the fringe pattern and pale median spot are the only two characteristics that have thus far been 100% supported by DNA identified specimens"

now Samea castellalis
Samea castellalis Guenée, 1854 includes as a synonym [5150] Samea ecclesialis of authors not Guenée, 1854 in Landry (2016). True ecclesialis is not found north of Mexico. I've confirmed this with James Hayden. I see that all the specimens of Samea ecclesialis at BOLD are misidentified.

Robert reports back
that based upon his understanding of the species, all of the images we posted in the previous comment are multiplicalis. “Notice that the pale panel in the median area, on all the specimens is trapezoidal, not squarish like S. ecclesialis. After seeing both nearly year-around, ID becomes largely gestalt. For one thing, S. multiplicalis is noticeably smaller, at least on my sheet.”

We think we see the distinctions
you are making when we look at

but are not sure we can see them here

Do we have them mixed in together??

 
The first 3 all look correct.
The first 3 all look correct. The first 2 in the second row appear to be Samea ecclesialis. The third one probably is Samea ecclesialis but it's hard to be 100% sure without seeing a larger version of the photo. When you're dealing with lightly marked or worn individuals, a positive ID can be tricky.

 
Correct
Ken, I agree with your assessment here. Without even viewing the full size images, the first three stand out as multiplicalis, while the lower three appear to be ecclesialis. And upon review of the full size images, I have no reservation about that conclusion.

Regarding the discussion here:
Using the pale median area (particularly shape) alone as a diagnostic characteristic is too tricky, and not reliable enough in my opinion (the shape difference does not bear out in DNA sampled specimens) - no offense to Robert. There's honestly enough variation from lighter marked to darker marked specimens of either species to avoid relying on that characteristic for primary diagnostic criteria.

When I look at these photos, this is how I arrive at my ID conclusion.

1st) the marginal fringe of the FW from tornus to apex.
2nd) the pale median area of the FW - size and how it's divided

Those are the primary characteristics. Then for "supporting evidence" I look at the following (sometimes slightly more difficult to ascertain) characteristics.

3rd) the shape of the HW - angular verses more rounded
4th) the presence of conspicuous dark fringe on the HW apex (indicative of ecclesialis)

Often the FW marginal fringe alone is enough for a pretty solid ID in fresher specimens, but taking the sum total of these four characteristics, I find separating the two species not that difficult. And so far, DNA sampled specimens bear out these characteristics rather well.

P.S. - Ken, the only difference I'd make to your photo is to enlarge the circle for point #1. The dark fringe actually starts just slightly further back at the inner margin and terminates at the tornus (giving that "arrow-like" shape). Other than that, looks good.

 
Sent an email to Robert Lord
with our suggestions for moving possibly misplaced images. Happy to send it to anyone else who is willing to take on this genus.