Seasonal-polymorphism
Guides
Nathalis iole
dainty sulphur, dwarf yellow
Nathalis iole, commonly known as the dainty sulphur or dwarf yellow, is the smallest North American pierid butterfly. It exhibits remarkable morphological variability, including seasonal wing coloration changes and distinctive structural features that have prompted suggestions it warrants a separate subfamily within Pieridae. The species occupies diverse open habitats, migrates south for winter survival, and has been documented performing elaborate courtship displays including a newly described facultative male display behavior.
Pieris oleracea
Mustard White
Pieris oleracea, the mustard white, is a butterfly in the family Pieridae native to Canada and the northeastern United States. The species exhibits two distinct seasonal forms: spring individuals display prominent green or yellow venation on the hindwing undersides visible even from above, while summer individuals appear nearly all-white with fainter markings. Populations are currently declining due to the invasive spread of garlic mustard (Alliaria petiolata), which is toxic to larvae despite attracting ovipositing females. The species is biovoltine in most of its range, with two broods annually, though southern Ontario populations may produce three to four generations and northern populations sometimes only one.
Piezodorus lituratus
gorse shield bug
Piezodorus lituratus, commonly known as the gorse shield bug, is a shield bug species in the family Pentatomidae. Adults reach 10–13 mm in length and exhibit seasonal color polymorphism: bright green in spring after emergence from hibernation, developing purplish-red markings on the pronotum and corium in late summer, and becoming paler before hibernation. The species is associated with leguminous host plants, particularly broom and dyer's greenweed, and is found across Europe, Africa, Northern Asia, and North America.
Pimplinae
Pimplinae is a worldwide subfamily of parasitoid wasps within Ichneumonidae. Members are primarily parasitoids of Holometabola, especially Lepidoptera pupae, with some species attacking spider egg sacs and adults. The subfamily includes 72 genera organized into four tribes: Delomeristini, Ephialtini, Pimplini, and Theroniini. Species are generally sturdy black wasps with orange markings and possess a diagnostic box-like first tergite with the spiracle positioned anterior to the middle.
Polyphemus pediculus
Polyphemus pediculus is a predatory freshwater cladoceran crustacean in the family Polyphemidae. It is distributed throughout the Northern Hemisphere but exhibits significant genetic structuring, representing at least nine largely allopatric cryptic species rather than a truly cosmopolitan population. The species displays complex reproductive behavior involving both parthenogenetic and gamogenetic (sexual) phases, with pronounced seasonal and daily rhythms in swarming activity.
Thaumatomyia
cereal flies, frit flies
Thaumatomyia is a genus of small flies in the family Chloropidae, commonly known as cereal flies or frit flies. The genus includes species with divergent larval ecologies: some are predatory on root aphids in agricultural soils, while others have been observed feeding on plant exudates. Several species are recognized as important biological control agents of root aphids in sugar beet and cereal crops in Middle Asia.
Winterschmidtiidae
Winterschmidtiidae is a family of over 140 mite species in the order Astigmata, distributed worldwide. The family comprises four subfamilies with distinct ecological specializations: Ensliniellinae associated with Hymenoptera (especially wasps and bees), Winterschmidtiinae with wood-boring beetles, Saproglyphinae with decaying materials and fungi, and Oulenziinae with leaves, vertebrate nests, and stored foods. Many species exhibit complex life cycles synchronized with insect hosts, including phoretic deutonymphs for dispersal and seasonal polymorphisms for environmental resistance.