Throybes confusion

Chris J. Durden drdn at
Wed May 2 11:14:34 EDT 2001

Good work Ron!
    And then there is *Thorybes albofasciatus* in Texas, Arizona and 
Mexico, that is usually misidentified as *T. pylades*. Then there are the 
genitalic forms of  *Erynnis horatius* and of *Copaeodes minima*. So many 
tails - so little time.
    The best time to look at the genitalic characters is during spreading. 
The apparatus may be extruded using needlenose forceps, and snipped, 
leaving an abdomen that is still on the specimen (available for later DNA 
sampling) and not very much truncated. Put the genitalic apparatus in warm, 
strong detergent water to flush the fats without depigmenting or weakening 
the hair pencils or scale brushes (or in females, removing the sphragis in 
those species that have them). The apparatus may be examined, drawn, 
photographed or videod in alcohol at this point. It is then dried on a 
blotter and placed in a gelatin capsule that is pinned under the specimen 
for future reference. This avoids the possibility of loss of separately 
stored slides which always seems to happen to key specimens.
...................Chris Durden

At 02:17 AM 5/2/2001 -0400, you wrote:
>My first encounters with Thorybes confusis (Confused) and bathyllus
>(Southern) was in 1968 while living in Pensacola, Fla. By the time I moved
>to Charleston in 1970 I was confused by the facies of numerous specimens I
>had encountered in FL and SC. So I decided to take a more scientific look
>at these two. The genitalia of these two are large and easily dissected and
>very different.
>By examining the genitalia of various samples I found that the spring brood
>of bathyllus looks identical to, or often darker than, the summer brood of
>confusis. I also found that true spring confusis are almost unspotted on
>the dorsal wings of males and lightly marked in females. In both species
>their respective spring broods are much less spotted than their respective
>summer broods. Since then I have examined probably 3 to 4 hundred specimens
>in institutional and private collections. Invariably the spring brood of
>bathyllus is misidentified as confusis in these collections. I have also
>seen many summer confusis misidentified as bathyllus. The same holds true
>for sight records.
>This lack of accurate identification is equal with collectors and watchers
>because both have based their determinations on the figures in the
>literature, which are often inaccurate, incomplete, or only of the summber
>broods. Virtually all skipper experts agree with Allen in the Butterflies
>of West Virginia that many specimens can only be told apart by dissection.
>(His determinations are correct - except I think his ventral confusis is a
>female by the shape of its HW.)
>So do some specimens have to be killed and dissected to know for sure which
>taxon they are? Not after you read this post. Here is how to tell them
>The summer brood of Southern Cloudys (bathyllus) are very boldly marked.
>The hindwings have a distinct almost white margin, and the four tiny
>hyaline spots at the apex of the forewing are ALWAYS in a straight line and
>look almost like one triangular spot - the small picture at the right in
>the Audubon Guide
>The summer brood of Confused Cloudys (confusis) have dark or only slightly
>lighter HW margins, their FW spots are not as pronounced but are usually
>very evident, the line of tiny spots at the apex ALWAYS has the last spot
>strongly disjunct toward the apex. - Yes, that would make the big
>"bathyllus" in the Audubon Guide actually a summer confusis female! (The
>Eastern specimen above it is also a likely misidentification. I have spring
>bathyllus females which look just like that.)
>The spring brood of bathyllus looks like that of summer confusis ( or even
>less spotted), the only sure way to tell them 99% is the shape of the line
>of spots at the apex which are ALWAYS in a straight line.
>The spring brood of confusis is as described above. The only 99% positive
>sight character is the alignment of those apical spots which ALWAYS have
>the last one (into the wing) clearly offset toward  the outside (margin) of
>the wing.
>Anyone who argues with this is wrong. I dissected a lot of specimens 20
>years ago and the only 99% correlation between the genitalia and the
>markings in all broods for both species was the alignment of the apical
>line of spots. Don't let the field guides or your eyes fool you. A lot of
>very experienced people have mistaken (and are mistaking) lightly marked
>spring Southerns (bathyllus) for Confused (confusis) and more heavily
>marked summer Confused (confusis) for Southerns (bathyllus).
>Should I address juvenalis and horatius next? There are some surprises here
>too if you check the genitalia.
>Good IDing


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