Are you certain enough of this for me to move it to a guide?

I always measure Tibicen when I can. Most of my other shots of this genus have legths given in the caption--I don't include the ruler for aesthetic reasons.

Patrick Coin
Durham, North Carolina

I wouldn't give an Id unless I was certain. Based on the level of information to hand (which is better than most) this key's out to be T. davisi and falls well within the parameters of what is known to be in North Carolina. In fact because it is in North Carolina, that is the reason I say this is davisi rather than canicularis because the two are so similar.

OK, the reason I was confused was because this specimen, seen precisely two years earlier at almost the same location (my neighborhood, moribund on the road) was the same size, body length 24 mm, head to wingtips 36 mm, and the pattern and pruinosity looks identical:



Andy Hamilton identified that indvidual as T pruinosa. I guess there is some disagreement between you. I know he has stated he is not as familiar with the southern species.

I guess I'll move them both to T. davisi. Gosh, this has to be the trickiest genus of really large insects around.

Patrick Coin
Durham, North Carolina

Yes you are correct on both accounts. More than one species of cicada can inhabit a geographical area. All Tibicens have some level of pruinosity especialy in the ventral area and each have different degrees of pruinosity given its age. The pruinosity has a tendancy to develop slowly over time and gets more and more prominent.

With regards to this specimen I still wouldn't call this one T. davisi because I do see diffences between these two. For example the shing black stripe down the middle of the abdomen. In davisi and canicularis, it's not as shiny and thick as this one. Also in the dorsal view, the abdomen is way too shiny.

And still, I wouldn't call it pruinosa either for the simple fact that it is too small given your measurements. There are other species of Cicadas which have recently been documented and are believed to be sub-species of pruinosa and other Cicadas. Examples that come to mind are T. winnemanna and T. robinsonianna among others. But these are too new even for me to make a positive ID.

T. pruinosa's wing length is usually over 38 mm from wing hinge to wing tip. I have noticed this specimen in the guide before but was reluctant to comment on it because of all its peculiarities. I think it would be safest to move this to Tibicen.