This is in Dennis Paulson’s Costa Rican Field Guide [2021] as Lestes tikalus which is a “junior synonym”.
There is a second pruinose spreadwing in Costa Rica, L. sigma (Chalky Spreadwing). To distinguish the two, Dennis’s book states that L. scalaris:
has faint metallic median and humeral stripes lacking pruinosity
However, my specimen appears to have pruinosity on the whole of the thorax.
A second distinguishing feature is that L. sigma has S2 half pruinose whereas that of L. scalaris is clear.
Despite these slightly mixed signals, this was confirmed on iNaturalist as L. scalaris.
| male | ||
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