
Hornfaced mason bee (Osmia cornifrons) emerging from cocoon. Female. Swarthmore, PA.

Downy yellowjacket (Vespula flavopilosa) on tree trunk. Crum Woods, Swarthmore, PA.

Oak pea gall wasp (Acraspis pezomachoides) on white oak. Hildacy Preserve, Media, PA.

Oak pea gall wasp (Acraspis pezomachoides) on white oak. Hildacy Preserve, Media, PA.

Cross section of larger apple oak gall (Amphibolips quercusinanis). Collected from Quercus bicolor. Swarthmore, PA.

Larger empty oak apple gall wasp (Amphibolips quercusinanis). Crow’s Nest Preserve, Elverson, PA.

Ampulex canaliculata. Ridley Creek State Park, Media, PA.

Ancistrocerus antilope building nest. Swarthmore, PA.

Andricus nigricens gall on underside of swamp white oak (Quercus bicolor) leaves. Crum Woods, Swarthmore, PA.

Andricus quercusflocci gall on upper side of white oak leaf. ID tentative. Approximately 6 mm in diameter. Hildacy Preserve, Media, PA.

Leafy oak gall (Andricus quercusfoliatus) on Quercus gemminata. Highlands Hammock State Park, Sebring, FL.

Leafy oak gall (Andricus quercusfoliatus) on Quercus gemminata. Highlands Hammock State Park, Sebring, FL.

Larva of leafy oak gall (Andricus quercusfoliatus) on Quercus gemminata. Highlands Hammock State Park, Sebring, FL.

Leafy oak gall (Andricus quercusfoliatus) on Quercus gemminata. Highlands Hammock State Park, Sebring, FL.

Wool-bearing gall wasp (Andricus quercuslanigera) on sand live oak. Archbold Research Station, Venus, Florida.

Anomalon sp. Zolfo Springs, FL.

Anomalon sp.. Zolfo Springs, FL.

European wool carder bee (Anthidium manicatum). Mohonk Mountain House, New Paltz, NY.

Exit hole of Aphidius sp. Swarthmore, PA.

Aphidius sp. ID tentative. Swarthmore, PA.

Western honey bee (Apis meliffera) visiting moist soil for water. Swarthmore, PA.

Western honey bee (Apis mellifera) on verbena. Mohonk Mountain House, New Paltz, NY.

Western honey bee (Apis mellifera) foraging on crocus. Swarthmore, PA.

Western honey bee (Apis mellifera) on eucalyptus flower. Griffith Park, Los Angeles, CA.

Western honey bee (Apis mellifera) nectaring on swamp milkweed. Saugerties, NY.

Western honey bee (Apis mellifera) foraging for water. Swarthmore, PA.

Poison-ivy sawfly (Arge humeralis). Hildacy Preserve, Media, PA.

Astata unicolor. Male. Stoneleigh Gardens, Villanova, PA.

Augochlora pura on fabric. Springfield, PA.

Pure green sweat bee (Augochlora pura) in bindweed flower. Swarthmore, PA.

Augochlora pura collecting pollen from corn. Stroud Preserve, Chester County, PA.

Augochlora pura collecting pollen from corn. Stroud Preserve, Chester County, PA.

Pure green sweat bee (Augochlora pura) at a rotting log. Taylor Memorial Arboretum, Wallingford, PA.

Pure green Augochlora (Augochlora pura) on tomatillo flower. Swarthmore, PA.

Pure green Augochlora (Augochlora pura) on white snakeroot. Rose Tree Park, Media, PA.

Augochlora pura collecting pollen from corn. Stroud Preserve, Chester County, PA.

Auplopus mellipes at bee/wasp hotel. Swarthmore, PA.

Two-spotted bumble bee (Bombus bimaculatus) on tree trunk. Swarthmore, PA.

Brown-belted bumble bee (Bombus griseocollis). Myakka River State Park, Florida.

Bumblebee (Bombus sp.) collecting aphid honeydew on a spruce tree. Mohonk Mountain House, New Paltz, NY.

Common eastern bumble bee (Bombus impatiens). Mohonk Mountain House, New Paltz, NY.

Fuzzy-horned bumble bee (Bombus mixtus) on yellow flower. Fairbanks, Alaska.

Cuckoo wasp (Caenochrysis sp.) stalking a Trypoxylon collinum nest. Swarthmore, PA.

Cuckoo wasp (Caenochrysis sp.) stalking a Trypoxylon collinum nest. Swarthmore, PA.

Heads of Caliroa sp. larvae. Little Crum Creek Park, Swarthmore, PA.

Oak leaf skeletonized by Caliroa sp. Little Crum Creek Park, Swarthmore, PA.

Honeycomb leaf gall wasp (Callirhytis favosa). Little Crum Creek Park, Swarthmore, PA.

Furry oak leaf gall wasp (Callirhytis furva). Jessup, PA.

Southern live oak stem gall wasp (Callirhytis quercusbatatoides). Highlands Hammock State Park. Sebring, FL.

Southern live oak stem gall wasp (Callirhytis quercusbatatoides). Highlands Hammock State Park. Sebring, FL.

Oak wart gall (Callirhytis quercusfutilis). Little Crum Creek Park, Swarthmore, PA.

Oak wart gall (Callirhytis quercusfutilis). Little Crum Creek Park, Swarthmore, PA.

Wooly catkin gall wasp (Callirhytis quercusoperator). Mohonk Mountain House, New Paltz, NY.

Chelonus sp. Zolfo Springs, FL.

Chelostoma philadelphi in flight. Swarthmore, PA.

Chelostoma philadelphi with pollen load. Swarthmore, PA.

Chelostoma philadelphi. Swarthmore, PA.

Chelostoma philadelphi trying to evict a club-horned cuckoo wasp (Sapyga louisi) from nest. Swarthmore, PA.

Chelostoma philadelphi. Swarthmore, PA.

Cucko wasp (Chrysis sp.) at bee/wasp hotel. Swarthmore, PA.

Cucko wasp (Chrysis sp.) at bee/wasp hotel. Swarthmore, PA.

Bristly rose sawfly (Cladius difformis) larva. Swarthmore, PA.

Bristly rose sawfly (Cladius pectinicornis). Swarthmore, PA.

Coelichneumon navus on fungus. Ridley Creek State Park, Media, PA.

Coelichneumon vitalis on forest floor. Mohonk Mountain House, New Paltz, NY.

Unequal cellophane bee (Colletes inaequalis) foraging on eastern redbud.

Unequal cellophane bee (Colletes inaequalis) foraging on eastern redbud.

Rufous-backed cellophane bee (Colletes thoracicus). Swarthmore, PA.

Conura sp. on tomato leaf. Zolfo Springs, FL.

Conura sp. on tomato leaf. Zolfo Springs, FL.

Hornworm parasitoid wasp (Cotesia congregata) on tobacco hornworm (Manduca sexta). Swarthmore, PA.

Cocoons of the white butterfly parasite (Cotesia glomerata). John Heinz National Wildlife Refuge, Philadelphia, PA.

Cryptinae. Guanacaste province, Costa Rica.

Unidentified wasp in Cryptinae. Swarthmore, PA.

Cynipidae (asexual morph). Subapterous. Hildacy Preserve, PA.

Dialictus sp. on tomato flower. Swarthmore, PA.

Dialictus sp. on tomato flower. Swarthmore, PA.

Blackberry root gall wasp (Diastrophus nebulosus). Rushton Woods Preserve. Willistown, PA.

Blackberry knot gall wasp (Diastrophus nebulosus) larva. Rushton Woods Preserve, Willistown, PA.

Blackberry knot gall wasp (Diastrophus nebulosus) larvae. Rushton Woods Preserve, Willistown, PA.

Blackberry root gall wasp (Diastrophus nebulosus). Longwood Gardens, Kennett Square, PA.

Digonogastra sp. Near bee hotel. Swarthmore, PA.

Dipogon sayi with crab spider (possibly Misumessus oblongus). Ridley Creek State Park, Edgmont, PA USA.

Cocoon of the rough oak bullet gall wasp (Disholcaspis quercusmamma). Crum Woods, Swarthmore, PA.

Oak rough bulletgall wasp (Disholcaspis quercusmamma) on swamp oak (Quercus bicolor). Crum Woods, Swarthmore, PA.

Disholcaspis quercusvirens on live oak. Highlands Hammock State Park, Sebring, FL.

Baldfaced hornets (Dolichovespula maculata) imbibing sap from the base of a tree. Rose Tree Park, Media, PA.

Baldfaced hornet (Dolichovespula maculata). Swarthmore, PA.

Bald-faced hornet (Dolichovespula maculata). Overwintering queen. Swarthmore, PA.

Baldfaced hornet (Dolichovespula maculata). Swarthmore, PA.

Baldfaced hornet (Dolichovespula maculata). Swarthmore, PA.

Ants (Ectatomma) on leaf. Guanacaste Province, Costa Rica.

Ectemnius sp. on pine tree. Taylor Memorial Arboretum, Wallingford, PA.

Ectemnius sp. on pine tree. Taylor Memorial Arboretum, Wallingford, PA.

Ephialtini. Ridley Creek State Park, Edgemont, PA.

Eremnophila aureonotata. Stroud Preserve, West Chester, PA.

Boll’s potter wasp (Eumenes bollii). Crooked River National Grassland, Madras, OR.

Fraternal potter wasp (Eumenes fraternus) collecing mud for nest. Female. Newfoundland, PA.

Eumenes sp. Myakka River State Park, Florida.

Nests of potter or mason wasp (Eumeninae) on underside of rock. Unionville serpentine barren, Unionville, PA.

Euodynerus sp. larva inside artificial nesting tube. Swarthmore, PA.

Euodynerus megaera at bee/wasp hotel. Swarthmore, PA.

Euodynerus megaera at bee/wasp hotel. Swarthmore, PA.

Euodynerus megaera scraping material off a leaf. Female. Very similar in appearance to Euodynerus schwarzi. Swarthmore, PA.


Euodynerus schwarzi applying mud cap to brood tunnel. Swarthmore, PA.

Euodynerus schwarzi applying mud cap to brood tunnel. Swarthmore, PA.

Euodynerus (Species F). Details at https://cjai.biologicalsurvey.ca/bmc_05/35e_spf.html. Swarthmore, PA.

Chelonus sp. Zolfo Springs, FL.

Ant (Formica sp.) eating a dead shrew. Swarthmore, PA.

Ligated furrow bee (Halictus ligatus). Male. Crooked River National Grassland, Madras, Oregon.

Brown-legged grass-carrying wasp (Isodontia auripes) at bee/wasp hotel. Swarthmore, PA.

Isodontia auripes (brown-legged grass-carrying wasp). Swarthmore, PA.

Hole plug of a grass-carrying wasp (Isodontia sp.) at a mason bee house. Longwood Gardens, Kennett Square, PA.

Sweat bee (Lasioglossum sp.) drinking sweat. Swarthmore, PA.

Sweat bee (Lasioglossum sp.) on yarrow. Tyler Arboretum, Media, PA.

Smaller yellow ant (Lasius claviger) queen on snow. Hildacy Preserve, Media, PA.

Smaller yellow ant (Lasius claviger) on snow. Queen. Hildacy Preserve, Media, PA.

Smaller yellow ant (Lasius claviger) on snow. Queen. Hildacy Preserve, Media, PA.

Lestica sp. excavating a nest in pine tree bark. Taylor Memorial Arboretum, Wallingford, PA.

Leucospis affinis at bee hotel. Swarthmore, PA.

Litomegachile sp. on swamp milkweed. Swarthmore, PA.

Macrophya formosa. Hildacy Preserve, Media, PA.

Sawfly larva (Macrophya sp.) on elderberry. Mohonk Mountain House, New Paltz, NY.

White-footed leafcutter bee (Megachile albitarsis) cutting a leaf. Zolfo Springs, FL.

White-footed leafcutter bee (Megachile albitarsis) with a leaf section. Zolfo Springs, FL.

White-footed leafcutter bee (Megachile albitarsis) cutting a leaf disc out of air potato (Dioscorea bulbifera). Zolfo Springs, FL.

White-footed leafcutter bee (Megachile albitarsis) cutting a leaf. Zolfo Springs, FL.

White-footed leafcutter bee (Megachile albitarsis) resting with cut leaf. Zolfo Springs, FL.

Giant resin bee (Megachile sculpturalis) at bee hotel. Swarthmore, PA.

Giant resin bee (Megachile sculpturalis) at bee hotel. Swarthmore, PA.

Giant resin bee (Megachile sculpturalis) at bee hotel. Swarthmore, PA.

Nest plug of a sculptured resin bee (Megachile sculpturalis). Swarthmore, PA.

Sculptured resin bee (Megachile sculpturalis. Upper Freehold, NJ.

Unidentified Megachilini on milkweed. Saugerties, NY.

Unidentified Megachilini on milkweed. Saugerties, NY.

Green’s giant ichneumonid wasp (Megarhyssa
macrurus) ovipositing into a rotting branch of red maple. Ridley Creek State Park, Media, PA.

Long-tailed giant ichneumon wasp (Megarhyssa macrurus) ovipositing into red maple. Ridley Creek State Park, Media, PA.

Two-spotted long-horned bee (Melissodes bimaculatus) clamped to leaf. Swarthmore, PA.

Long-horned bee (Melissodes sp.) on sunflower. Swarthmore, PA.

Melissodes trinodis on sunflower. Female. Swarthmore, PA.

Monodontomerus sp. at bee and wasp house. Swarthmore, PA.

Monodontomerus sp. at bee and wasp house. Swarthmore, PA.

Monodontomerus sp. at bee and wasp house. Swarthmore, PA.

Monodontomerus sp. at bee and wasp house. Swarthmore, PA.

Yellow ants (Monomorium floricola) on cow skull. Also know as the bicolored trailing ant. Zolfo Springs, FL.

New World banded Thynnid wasp (Myzinum sp.). Pioneer Park, Zolfo Springs, FL.

Nealiollus sp. ovipositing into a Berkeley’s polypore. Stoneleigh Gardens, Villanova, PA.

Nealiollus sp. ovipositing into a Berkeley’s polypore. Stoneleigh Gardens, Villanova, PA.

Oak potato gall (Neuroterus quercusbatatus). Little Crum Creek Park, Swarthmore, PA.

Neurotoma edwardi. Stroud Preserve, West Chester, PA.

Nomad bee (Nomada, luteola species group). Female. Swarthmore, PA.

Nomad bee (Nomada sp.). Crow’s Nest Preserve, Elverson, PA.

Trap-jaw ant (Odontomachus ruginodis) in antlion trap. Highlands Hammock State Park, Sebring, FL.

Female braconid in the genus Opius. Emerged from a dodder gall weevil (Smicronyx sculpticollis) growing on Cuscuta. Saugerties, NY.

Horn-faced mason bee (Osmia cornifrons) at mason bee house. Swarthmore, PA.

Horn-faced mason bee (Osmia cornifrons) capping nesting hole with mud. Swarthmore, PA.

Horn-faced bee (Osmia cornifrons) on window. Swarthmore, PA.

Georgia mason bee inside an observation tunnel at insect hotel. Female. Mites on thorax are kleptoparasitic Chaetodactulus. Swarthmore, PA.

Taurus bee (Osmia taurus) in nesting hole. Swarthmore, PA.

Taurus mason bee (Osmia taurus) at bee hotel. Male. Swarthmore, PA.

Male taurus mason bees (Osmia taurus) at bee hotel. Swarthmore, PA.

Taurus mason bee (Osmia taurus) finishing a mud cap on a nest. Swarthmore, PA.

Parancistrocerus histrio. Swarthmore, PA.

Golden paper wasp (Polistes auriferResearch Grade) on surface of water. Kalaoa, HI.

Polistes bellicosus at nest. Zolfo Springs, FL.

Polistes dorsalis ssp. dorsalis eating honeydew on citrus leaf. Zolfo Springs, FL.

Polistes dorsalis ssp. dorsalis eating honeydew on citrus leaf. Zolfo Springs, FL.

Polistes dorsalis ssp. dorsalis eating honeydew on citrus leaf. Zolfo Springs, FL.

Polistes dorsalis ssp. dorsalis eating honeydew on citrus leaf. Zolfo Springs, FL.

Nest of of Polistes dorsalis dorsalis. Myakka River State Park, Sarasota, FL.

Dark paper wasp (Polistes fuscatus) ripped in half by a Chinese mantis (Tenodera sinensis). Cheslen Preserve, Chester County, PA.

Variegated paper wasp (Polistes versicolor) nest. Urbina Bay, Isla Isabela, Galápagos.

Polistes bellicosus. Zolfo Springs, FL.

Oak leak gall midge (Polystepha pilulae). Crum Woods, Swarthmore, PA.

Oak leak gall midge (Polystepha pilulae). Crum Woods, Swarthmore, PA.

Oak leak gall midge (Polystepha pilulae). Crum Woods, Swarthmore, PA.

Spider wasp (Pompilidae) with spider. Possibly Phanagenia bombycina or Auplopus carbonarius. Taylor Memorial Arboretum, Wallingford, PA.

Small honey ant (Prenolepis imparis) with aphids. Hildacy Preserve, Media, PA.

Small honey ant (Prenolepis imparis) with aphids. Syrphid fly larva is also present. Hildacy Preserve, Media, PA.

Small honey ants (Prenolepis imparis). Queen and two males. Swarthmore, PA.

Small honey ants (Prenolepis imparis) feeding on tree sap. Smedley Park, Springfield, PA.

Small honey ants (Prenoleis imparis) drinking tree sap in winter. John Heinz National Wildlife Refuge, Philadelphia, PA.

Sapyga louisi near nest of Chelostoma philadelphi. Swarthmore, Pennsylvania.

Sapyga louisi in nesting hole. Swarthmore, PA.

Sphecius speciosus (eastern cicada killer). Male, guarding territory. Swarthmore, PA.

Eastern cicada killer (Sphecius speciosus) on coneflower. Swarthmore, PA.

Eastern cicada killer (Sphecius speciosus) dragging a paralyzed cicada to burrow. Swarthmore, PA.

Canadian potter wasp (Symmorphus canadensis) collecting mud for nest. Taylor Memorial Arboretum, Wallingford, PA.

Tufted potter wasp (Symmorphus cristatus) drinking water at a bird bath. Swarthmore, PA.

Unidentified sawfly larva (Tenthredinoidea). Mohonk Mountain House, New Paltz, NY.

Narrow stingless bees (Tetragonisca angustula). La Selva, Costa Rica.

Immigrant pavement ant (Tetramorium immigrans) on a Pepperidge Farm Goldfish. Swarthmore, PA.

Tetrastichinae on cypress gall. Zolfo Springs, FL.

Thrinax dubitata. ID tenative. One of two sawflies that eats sensitive fern (Onoclea sensibilis). The other, Thrinax albidopicta, is not found in Pennsylvania.Taylor Memorial Arboretum. Wallingford, PA.

Thrinax dubitata gall on sensitive fern (Onoclea sensibilis). ID based on adults on same plant. Crow’s Nest Preserve, Elverson, PA.

Thrinax dubitata larva on sensitive fern (Onoclea sensibilis). Formerly Hemitaxonus dubitatus. Taylor Memorial Arboretum, Wallingford, PA.

Galápagos carpenter bee (Xylocopa darwini) on goat’s head (Tribulus terrestris). Newly introduced to Genovesa Island. Galápagos Islands, Ecuador.

Triepeolus sp. attached to Iris leaf. Swarthmore, PA.

Sintgless bees (Trigona sp.) collecting honeydew from Mexican treehopper nymphs. Playa del Carmen, Mexico.

Trypoxylon sp. near bamboo sections. Tyler Arboretum, Media, PA.

Trypoxylon sp. female. Tyler Arboretum, Media, PA.

Male Trypoxylon sp. guarding nest. Tyler Arboretum, Media, PA.

Trypoxylon collinum near nesting hole. Swarthmore, PA.

Male Trypoxylon collinum in hole. Swarthmore, PA.

Trypoxylon collinum guarding nest. Swarthmore, PA.

Pair of Trypoxylon collinum at nest. Provisioning nest with paralyzed spiders. Swarthmore, PA.

Trypoxylon-collinum fighting off a cuckoo wasp (Caenochrysis sp.). Swarthmore, PA.

Trypoxylon drinking water. Crooked River National Grassland, Madras, Oregon.

Trypoxylon drinking water. Crooked River National Grassland, Madras, Oregon.

German yellowjacket (Vespula maculifrons) eating a cricket. Worker. ChesLen Preserve, Coatsville, PA.

Galápagos carpenter bee (Xylocopa darwini) on goat’s head (Tribulus terrestris). Newly introduced to Genovesa Island. Galápagos Islands, Ecuador.

Eastern carpenter bee (Xylocopa virginica). Male. Swarthmore, PA.

Zapatella quercusphellos on bear oak (Quercus ilicifolia). Formerly named Callirhytis quercussimilis, among many others. Mohonk Mountain House, New Paltz, NY.

Zapatella quercusphellos on bear oak (Quercus ilicifolia). Formerly named Callirhytis quercussimilis, among many others. Mohonk Mountain House, New Paltz, NY.