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Genus Nylanderia - Crazy Ants

Nylanderia sp? - Nylanderia terricola - female Tiny red ants at nectaries - Nylanderia flavipes Unknown ant - Nylanderia faisonensis - female Formicidae - Nylanderia vividula Chalcidae?  - Nylanderia Unknown ant - Nylanderia terricola Ant in Anaheim California - Nylanderia Small
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
Superfamily Formicoidea (Ants)
Family Formicidae (Ants)
Subfamily Formicinae
Tribe Lasiini
Genus Nylanderia (Crazy Ants)
Anglicized -- nye-lan-DEER-ia
Latin -- nee-lan-DEHR-ia
Synonyms and other taxonomic changes
Formerly a subgenus of Paratrechina.
Explanation of Names
Nylanderia Emery, 1906 (as subgenus of Prenolepis)
patronym for the Finnish entomologist Nylander, who collected the type series (of the American species N. vividula!) in a greenhouse in Helsinki.
workers and males 2-2.6 mm
queens 2.75-4.5 mm
Small formicine ants, mandibles with five teeth, all species have nearly symmetrical (paired), stout, microsopically barbulate setae on the pro- and mesonotum and along the midline of the head.
most are associated with eastern deciduous forest, but a few occur in central grasslands and southwest desert riparian areas; Worldwide.
Nest in leaf litter, hollow nuts, rotting wood, soil or sand. Forage on the ground and on low vegetation.
Active throughout the growing season, these typically mass near the surface under bark or stones in spring, then retreat deeper as the weather warms. Mating flights of the majority of species occur late April-May, but a few, apparently including the parasites mentioned below, fly early summer. Alates of early-flying species are reared in late summer, then overwinter in the nest.
Generalist foragers, scavenge honeydew from leaf surfaces and detritus. Have been encountered with small litter arthropods in their mandibles, including fungus gnats! Attracted to both protein and sweet baits.
Life Cycle
Colony founding is independent in most species. Mature colonies are often somewhat diffuse in forest litter, especially in warm weather, with groups of workers and brood occupying suitable incubation spaces in the upper leaf litter or under bark, and queens, small larvae and other workers remaining deeper.
There are at least three, undescribed, microgynous species that are workerless parasites in the nests of other, abundant species.

This group contains some notable non-native species.
- N. flavipes is invasive in wooded areas of northeastern USA.
- N. bourbonica is abundant in human habitats in the Gulf Coast region.
- N. vividula probably originated in Mexico, but is now common in disturbed habitats across the southern US, including irrigated lands in the Southwest, and is also found outdoors in irrigated portions of Mediterranean southern Europe, the Middle East and North Africa, and occasionally in greenhouses to the north.