Invasive-species-impact
Guides
Adalia
ladybugs, lady beetles, ladybirds
Adalia is a genus of lady beetles (Coccinellidae) containing two species: A. bipunctata (two-spot ladybird) and A. decempunctata (ten-spot ladybird). These beetles are aphid predators found across the Palearctic region. Both species exhibit color pattern polymorphism and possess alkaloid chemical defenses. A. bipunctata is known to harbor multiple male-killing symbionts including Wolbachia, Rickettsia, and Spiroplasma, though symbiont phenotypes vary geographically.
Diceroprocta apache
citrus cicada, Apache cicada
Diceroprocta apache is a cicada species in the family Cicadidae, commonly known as the citrus cicada or Apache cicada. It has a median life cycle of three to four years from egg to adult death. The species is an important component of riparian food webs in desert regions. It serves as a documented host for the Pacific Cicada Killer wasp (Sphecius convallis). Research indicates its population density is negatively affected by invasive saltcedar (Tamarix ramosissima) monocultures and positively associated with native Goodding's willow (Salix gooddingii) canopy cover.
Gammarus fasciatus
Gammarus fasciatus is a freshwater amphipod native to North America. Laboratory studies demonstrate that food type significantly influences growth rates, with algae and animal matter supporting greater growth than detritus-based diets. The species serves as a host for the acephaline gregarine parasite Ganymedes oaklandi. In the Great Lakes region, populations have declined due to competition with the invasive Ponto-Caspian amphipod Echinogammarus ischnus.
Melanoplus islandicus
island short-wing grasshopper, forest locust, island locust
Melanoplus islandicus is a spur-throated grasshopper in the family Acrididae, found in coastal regions of Alaska, Canada, and the Great Lakes area. Populations have declined due to habitat loss and invasive species, prompting conservation concern. The United States Fish and Wildlife Service proposed it for Endangered Species Act listing in 2003, though it remains unlisted.
Nicoletia wheeleri
California mantis, Wheeler's mantis, California mantid
Nicoletia wheeleri is a native praying mantis species of western North America, historically known as Stagmomantis wheeleri or S. californica. It is a medium-sized mantid with variable green to brown coloration. The species has experienced population declines, potentially due to competition with introduced mantis species such as Mantis religiosa and Tenodera sinensis. It is one of five native mantis species recorded in California.
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.
Pieris virginiensis
West Virginia White, Toothwort White
Pieris virginiensis, the West Virginia White, is a small white butterfly endemic to moist deciduous forests of eastern North America. The species is univoltine, with adults active for approximately one month in early spring (April–May). It is threatened by habitat loss, forest fragmentation, and particularly by the invasive plant Alliaria petiolata (garlic mustard), which females mistakenly oviposit on due to chemical similarity with native host plants; larvae cannot survive on this toxic invasive. Population declines of 10–70% have been documented across its range.