Pearl Crescents

Here are a couple Pearl Crescents, fairly small and common butterflies here in New Jersey.

At least they're supposed to be Pearl Crescents. There theoretically could be Northern Crescents around here too, though that species is generally considered to be only in northern NJ. The Northern Crescent wasn't even considered to be a species until the 1980s [1]; before that they were just considered to be Pearl Crescents. When research showed that the butterflies we now consider to be Northern Crescents could hybridize with Pearl Crescents but their offspring had lower survivability they were spun off into a separate species. This is another example of where the line between species is subtle, and even debatable.

Or it could also be a Tawny Crescent. Tawny Crescents are also considered to be a very similar and more northern species, considered extirpated in NJ, so theoretically I can discount them entirely when doing identifications. I'm not certain they can hybridize with the other 2, though if they do I suspect that offspring survivability is lower than for non-hybrids.

These butterflies are considered to have differences, though there are also color/pattern variations within the species. I wouldn't be surprised if there are cases where even experts could disagree on which species they're looking at.

August 5, 2021 at Duke Farms
Photo 148951846, (c) jpviolette, some rights reserved (CC BY-NC)

The second individual is a bit more tattered.

August 5, 2021 at Duke Farms
Photo 148952783, (c) jpviolette, some rights reserved (CC BY-NC)


[1] They were documented back in 1837. I'm not sure if they were considered a subspecies of Pearl Crescent, or if they were initially considered a species then later considered a subspecies and has now gone back to being a separate species.

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