There are three species found in eastern Nebraska – Polygonia interrogationis, P. comma and P. progne. They differ from most other butterflies in that they overwinter as adults and often prefer rotting fruit or tree sap over flower nectar. These three species are quite similar in appearance and while there can be several color phases or forms the descriptions below will be adequate to identify them. While myself not having seen any Polygonia yet this year I have heard that all three have already been sighted this year. So a quick note on this group and how to identify them.
The Question Mark (Polygonia interrogationis) is so named for the silver marking on it’s ventral hindwing. This silver mark is curved with a separate spot underneath it thus forming a “question mark” from which it gets its common and species name. It can also be separated from comma and progne by the presence of a black bar on the upper forewing that the other two lack. It is generally larger than the other two but this is not a reliable trait. The Question Mark usually also has a more elongate profile while the other two appear “rounder”. Larvae feed on a wide variety of plants from elm trees to wood nettles.
The Eastern Comma is also named for the silver marking on its ventral hind wing. It lacks the silver dot beneath the silver “comma” marking from which it gets its name. As with the Question Mark, larvae feed on a wide variety of plants. It is sometimes referred to as the Hop Merchant due to its utilization of hops as a larval hostplant.
The silver marking on the Gray Comma (Polygonia progne) is shaped like a kinked straw – straight with a bend in the middle. It gets its name from its more gray shading of the ventral hindwing which is also slightly two toned with the base being darker than the outer portion. It is generally the smallest and rarest of the three, sometimes going unreported for a season or longer. It is also the most selective regarding its larval host plants, laying eggs almost exclusively on Ribes species (gooseberries and currants).
All three of these fly in multiple broods so they might be found at any time. Three times in 30+ years of observations I have hit the trifecta – finding all three species at the same locality on the same day. The first time was at/around Victoria Springs SRA in Custer county on June 30, 1990. The second was somewhere in Webster county on June 17, 2001 when a co-worker took me to his secret deer hunting location to look for Banded Hairstreaks (which we found as well). And then on June 23, 2011 all three were found at Red Fox SWMA in Stanton county.
There are a couple Polygonia species (zephyrus and satyrus) distributed in the western United States that have been found in the panhandle as well. Sightings of these two species are possible (but rare) in the western most counties of the state.