File talk:Kamelhalsfliege Phaeostigma major.jpg
Howdy / To who it may concern:
Yesterday I requested a rename on this file (per this edit) as imho the ID is incorrect. Today I see that the rename request is rolled back with a question to explain.
So: I can see where the original ID "came from" as the pterostigma seems to have only one cross vein. This is a "textbook" character for R. ophiopsis, so anyone looking at the "quick and dirty" way to ID this animal would go something like: "Germany (limiting the selection of available species); Black ptero with one cross vein => must be R. ophiopsis". In fact, I've seen this image many times before and maybe didn't take time to look closer, or just quickly glanced at the ptero too, or whatever, but anyway - no alarm bells went off.
On closer inspection however there is no way that this is ophiopsis. Wing veination in Snakeflies is quite variable and prone to aberrations, but will generally stick to "patterns at large". One typical aberration is in the cross veins of the pterostigma. Species that are documented as "having 1 cross vein" often have two and the Phaeostigmas with two cross veins sometimes have one, or more often (as in this particular case!!) one cross vein that forks inside the ptero. So the configuration of the ptero is not a 100% reliable character. Even so, this expression (one forked cross vein in ptero) is quite common on Phaeostigma, especially on major. More importantly however, one should look at the big picture of the total wing veination. The most striking feature here is that the 1st discoidal cel (the cel directly under the pterostigma (or in this case, as the wings are folded over the body, directly "above" the pterostigma) is located centrally above the ptero on Raphidia and usually shorter and "higher" than here, whereas on the German Phaeostigmas it is stongly shifted basally and much wider and lower. Exactly as seen here. Other than that on both Phaeostigma the wing veination is much "richer" than on Raphidia. This is most notable in the wing tip and on the hind edge of the wing (top edge in image). Here almost all veins that lead to the edge will be forked on Phaeostigma and unforked on Raphidia. This is even more notable on Phaeostigma notata (very "crowded" wing veination), but the difference between R.ophiopsis and this here P.major is clear and evident still. As another quick & dirty indicator one may count the cross veins in the costal area: Roughly under 10 for R.ophiopsis, about 10-12 for major, 12+ for notata (not bullet proof, but very indicative). That's all I have time for now. Gotto run. Pudding4brains (talk) 12:14, 12 September 2014 (UTC)
