Gregarious
Guides
Pteromalus cassotis
Pteromalus cassotis is a gregarious parasitoid wasp in the family Pteromalidae that specializes in attacking monarch butterfly chrysalides. A single female may lay numerous eggs in one host, with documented emergences of up to 425 adult wasps from a single chrysalis. The species exhibits extreme female-biased sex ratios, averaging 90% female offspring.
Pteromalus puparum
white butterfly pupal parasitoid wasp
Pteromalus puparum is a gregarious endoparasitoid wasp that attacks the pupal stage of butterflies, particularly pierids and papilionids. It is widely distributed and has been extensively studied for biological control of agricultural pests, notably Pieris rapae, the small white cabbage butterfly. The species exhibits sophisticated host manipulation through venom injection during oviposition, which suppresses host immunity and regulates development. It is a model organism for studying parasitoid venom biochemistry, reproductive strategies, and innate immunity.
Pyrrhocoris apterus
firebug, European firebug
Pyrrhocoris apterus, commonly known as the firebug or European firebug, is a striking true bug recognized by its vivid red and black coloration. Native to the Palaearctic region, it has expanded its range to North America, Central America, India, and Australia. The species exhibits pronounced gregarious behavior, with larvae and adults frequently forming aggregations of tens to hundreds of individuals. It is primarily seed-feeding, specializing on lime tree and mallow seeds. A notable feature is its non-functional wing polymorphism: populations contain rare long-winged (macropterous) individuals alongside the typical short-winged (brachypterous) form, though the species is effectively flightless.
Quesada gigas
Giant cicada, chichara grande, coyoyo, coyuyo, coffee cicada
Quesada gigas is a large cicada species native to North, Central, and South America, with the widest geographic range of any cicada in the Western Hemisphere. It is a significant agricultural pest, particularly of coffee (Coffea) in Brazil and paricá (Schizolobium parahyba var. amazonicum) in the Amazon region, where nymphal feeding on roots can cause substantial yield losses or tree mortality. The species exhibits low selectivity in oviposition site choice, with females documented laying eggs in dry branches of non-host plants such as Conyza spp. weeds, which cannot support complete nymphal development due to their annual life cycle.
Romalea microptera
Eastern Lubber Grasshopper, Lubber Grasshopper
Romalea microptera is a large, flightless grasshopper native to the southeastern United States, reaching up to 3.5 inches in length. Its aposematic coloration—yellow with black markings in eastern populations, black with red or yellow markings in western populations—serves as a warning to predators. Despite its formidable defensive arsenal including spines, body armor, chemical secretions, and threat displays, it is harmless to humans and rarely causes significant agricultural damage.
Scaphinotus ventricosus
potbellied snail-eating beetle, pot-bellied snail-eating beetle
Scaphinotus ventricosus is a species of ground beetle in the family Carabidae, commonly known as the potbellied snail-eating beetle. It is native to western North America, with documented occurrence in California and Oregon. Adults are distinctive among ground beetles for their brachypterous (short-winged) condition, which renders them flightless. The species exhibits gregarious and nocturnal behavior. It inhabits deciduous forests and poison-oak thickets, where it presumably feeds on snails as suggested by its common name and the feeding habits of related species in the genus.
Tachinaephagus
A genus of gregarious larval–pupal parasitoids in the family Encyrtidae. Species in this genus, particularly T. zealandicus, are known to attack synanthropic Diptera including muscoid flies and calliphorid carrion flies. They have been studied for biological control applications and forensic entomology due to their predictable development on decomposing remains.
Tachinaephagus zealandicus
Tachinaephagus zealandicus is a gregarious larval-pupal endoparasitoid wasp in the family Encyrtidae. It parasitizes larvae of synanthropic Diptera, particularly muscoid flies including Musca domestica and various Calliphoridae species associated with decomposing carrion. The species has been studied extensively for its potential in forensic entomology and biological control. Under laboratory conditions at 25°C, its life cycle completes in 23–27 days, with single hosts producing 3–18 adult parasitoids.
Xanthochilus saturnius
Mediterranean seed bug
Xanthochilus saturnius, commonly known as the Mediterranean seed bug, is a small true bug in the family Rhyparochromidae. It measures 6–8 mm and displays distinctive black-on-tan coloration. The species is native to southern Europe and the Mediterranean region, with established populations in North America. It feeds primarily on seeds of Lamiaceae and Scrophulariaceae plants.
Zadiprion rohweri
Pinyon Pine Sawfly
Zadiprion rohweri, commonly known as the Pinyon Pine Sawfly, is a species of conifer-feeding sawfly in the family Diprionidae. It is associated with pinyon pine (Pinus edulis and related species) in the southwestern United States and Mexico. The species was described by Middleton in 1931 and is one of several Zadiprion species specialized on pine hosts. Sawflies in this genus are known for gregarious larval feeding that can cause noticeable defoliation.