I took my family on a nature walk last weekend in the Scotia Barrens. Usually we go to watch dragonflies skim Ten Acre Pond, but it’s way too early in the season for that. This time we were scouting for cynipid galls on scrub oak (Quercus ilicifolia). They weren’t hard to find, and I counted at least four or five different kinds. I found this one especially interesting:
Here it is closer up. It’s about 5 cm (2 in.) long, from base to tip:
I determined that it was induced by Amphibolips quercusilicifoliae (Bassett, 1864), a gall wasp about which very little is known. The species was originally described by Homer Bassett, a librarian from Connecticut, as Cynips quercus ilicifoliae, and was known back then to occur in Pennsylvania and Connecticut. The phenotype of these galls seems quite similar to other species of Amphibolips, like A. acuminata. There’s probably a cool project here. Maybe when it warms up we’ll head to the barrens for some fresh galls.