The Azure complex in indeed just that, Complex!. No longer is it just “Spring” or “Summer” Azure. The different species have distinct and overlapping flight periods. It is this distinctive flight time that can assist you in a “What am I looking at?” best option depending on: 1) Where you are, 2) Time of year, 3) Habitat / Host plant proximity. If you’re NOT netting and studying the forewing scale patterns of azures in you can still “drill down” to a most likely and in some cases very, very probable species. Harry Pavulaan and David Wright have done extensive research over the last 25-30 years with the Azure complex and have described two new species within the last 15 years; Celastrina idella (Holly Azure – 1999) and Celastrina serotina (Cherry Gall Azure – 2005). Based on my limited experience in our local area and reading through their papers on the new species I’ve put together a summary of the typical yearly time frames of emergence. Harry Pavulaan has been very patient with this novice and agreed with the time tables I present here.
As a refresher: C. lucia is Northern Azure, C. neglecta is Summer Azure, C. ladon is Spring Azure, C. neglectamajor is Appalachian Azure, C. idella is Holly Azure, and C. serotina is Cherry Gall Azure. C. niger, Dusky Azure, is distinctive enough to be identified with a decent look at the dorsal side (BTW, if you find one please let me know(:>)
The below mentioned time frames can and will vary based on seasonal weather influences (e.g. the late season this year) but the emergence patterns will be relative regardless.
1. Earliest azure emergence begins in early April with the “spring” brood of C. neglecta
2. Within one or two weeks C. ladon begins and will continue into mid-May so there will be overlap with “spring” C. neglecta
3. C. Lucia follows in mid to late April (early May in area #2 on the map) and is restricted to the higher elevation counties OR the higher ridges in the eastern portion of the map (e.g. C. lucia on North mtn just west of Winchester, VA, etc). It completes in early May in the eastern portion of the region and lingers up until the end of May in western MD and WV (areas marked #2 on the map).
4. Around mid-May C. neglectamajor starts its flight and ends later in June.
5. Around mid-May C. serotina begins its flight in the western portion of the area. It has only been found in the western sections and will occupy the same areas as C. lucia (a week or two later). C. lucia by this time will begin to show signs of wear. This flight lasts until mid-late June.
6. The “summer” flight of C. neglecta can be expected starting around May 20th (give or take) in the eastern portion of the region and the bulk of the western flight occuring in late June in the mountains. There are uncommon exceptions of high elevation colonies emerging in mid-late May so “don’t be fooled” as Harry Pavalaan would say.
What does having this timetable do for me? Well, it helps me remember; 1)What the possibilities are now and 2) Can help me help drill down to an expected species based on the before mentioned criteria of location, time-of-year, habitat / proximity to host plants. April into early May will be toughest with most of the Azures being “spring/summer” unless netted and examined or seen ovipositing on a host. However, later in the season like now there are small windows when the most likely candidates can be better judged. A good example of this was recently (within the last couple of weeks) C. lucia was on the wing in the western county mountains. But now that we’re into June the first couple of weeks I would expect the C. lucia flight to be done, C. neglecta to begin ramping up, and the other in-flight Azures to be ether C. serotina or C. neglectamajor. At that point other criteria like proximity to host plant can be used to help drill down further.
I know you can’t put a label on them all or perhaps most until later in the season especially when not netting but at least you can get to a “best option”.