Our species profile for this issue is the Green Comma. The anglewings, or commas as they are also known, belong to the very large worldwide family Nymphalidae, the Brushfoots. In Washington we have four species of anglewings, all of which are included in the genus Polygonia. Most anglewings have a fairly similar appearance dorsally, bright tawny-orange punctuated with contrasting black spots. Anglewings are fairly large, and have a characteristic white angle-shaped mark near the middle of the ventral hindwing (VHW); this is the mark for which they are named. The pointed ‘elbow’ of this angle mark points down and backward, toward the tip of the abdomen. Anglewings are powerful darting flyers, but when flushed often return again and again to the same area, sometimes even landing on their human disturbers. Males often perch and wait for females, and both sexes draw nourishment from animal droppings, rotting fruit, tree sap or decomposing organic material. Anglewings rarely nectar on flowers.

Adults diapause over the winter and as a result all commas have a very long adult life expectancy. The reported flight period for Polygonia faunus is mid May through  September,  but individuals could also be seen at any time in the winter during any unseasonably warm weather period. An individual butterfly is likely to eclose from its chrysalis in July or August, and will still be flying in June of the following year. The Green Comma is a butterfly of moist wooded areas, and is found throughout the mountainous areas of Washington on both sides of the Cascades. P. faunus is absent only from the far western maritime zone and from the dry parts of the Columbia Basin. The Green Comma is a new world species, ranging from British Columbia south to central California, and east to Montana and New Mexico. It also ranges east across Canada and is found in the northernmost midwest, also in New England and south along the Appalachians as far as northernmost Georgia.

Adults typically eclose from their pupae in late July or August. After feeding for a short time they enter a summer dormancy period, spending much of their time quietly resting in a shady area. As the hot days of summer give way to autumn the Green Comma, together with other species of Polygonia, become very active, seeking nutrition to tide them through the winter. During such times anglewings can be abundant in some areas, such as unpaved roadsides and wet spots in the northern forests. As the days become shorter and colder the adult butterflies find protected areas where they will diapause through the winter.

Green Commas again become active with the earliest sunny days of spring. Mating apparently does not take place until late May or early June, and oviposition occurs throughout June in Washington. The Green Comma uses willows as its larval foodplant, the Sitka Willow, Salix sitchensis, apparently being the overwhelming favorite in this region. Eggs are laid singly on the leaves or catkins of the host plant. Egg stacking, common in other Polygonia, is not often seen in P. faunus. Eggs hatch in 4 to 5 days and the larvae, like most brushfoots, bear flexible branched spines. Green Comma larvae do not build nests and do not leave the host plant, feeding and resting on the under surface of the willow leaf. The larva grows quickly, pupating about 30 days after egg hatch. The brown angular chrysalis is pointed at both ends and constricted in the middle, and hangs from a single attachment (cremaster) at the posterior end. The adult butterfly ecloses about two weeks after pupation.

Most easily identified by the VHW, P. faunus males are colored dark brown to almost black, darker on the proximal half of the wing and with a broad gray band on the outer half.  Fresh males have a diagnostic double row of pea green chevrons in the lighter band. Females, less frequently seen, are almost unicolor on the VHW, gradually varying from chocolate brown at the base to dark hoary gray at the extremity. Other species of anglewings have a VHW coloration of cinnamon brown (Satyr Comma) or streaky gray (Hoary Comma). Only the rare Oreas Comma is easily confused with P. faunus, it having an even darker VHW.

All Photos by Dave Nunnallee

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