Common flowerbug
Adult of Anthocoris nemorum
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hemiptera
Suborder:	Heteroptera
Family:	Anthocoridae
Genus:	Anthocoris
Species:	A. nemorum
Binomial name
Anthocoris nemorum (Linnaeus, 1761)

The common flowerbug (Anthocoris nemorum) is a common minute pirate or flower bug.^[1] A. nemorum was first described by Carl Linnaeus in 1761 in his Systema Naturae. A. nemorum is widely distributed across Europe and parts of Asia, extending into temperate regions of North America. Adults measure 3-4 mm and are recognized for their elongated bodies and reflective forewings. The species is valued in agriculture as a natural enemy of Aphid, Psyllid, Thrips, mites, and small caterpillars, making it an important component of Integrated pest management (IPM) programs. A. nemorum thrives in diverse habitats, including hedgerows, forests, orchards, and vegetable crops, and its ability to overwinter in bark and leaf litter ensures persistence across seasons. By reducing reliance on chemical pesticides, this generalist predator contributes to sustainable crop protection and ecological balance. It is considered beneficial in agriculture due to its role in controlling aphid populations^[2]. It has been used as a biological pest control since 1992, primarily to control Cacopsylla pyri.^[3] Adults can be found all year.^[4] A. nemorum lays its eggs inside plant leaves^[5] often in groups of 2-8. Larvae hatch light reddish-brown and develop into adults over several weeks. Adults overwinter beneath bark or leaf litter, which allows populations to persist across seasons ^[6]. It is capable of biting humans.^[7]

The common flowerbug is found across Europe and the Palearctic to China.^[8][9] It is common in Great Britain and Ireland.^[1] In the Alps it is found to about 2000 meters above sea level.^{[citation needed]}

It more commonly inhabits lower moist, shaded vegetation than trees,^[10] and especially nettles in the later half of the growing season.^[11] The species thrives in diverse habitats, ranging from hedgerows and deciduous forests to agricultural landscapes. In orchards, A. nemorum is frequently observed on apple and pear trees, where its ovipositor preferences align with high prey availability ^[12]. In cabbage fields, it contributes to pest suppression by preying on cabbage aphids and diamondback moth larvae, demonstrating its adaptability to vegetable crops ^[13]. The species has also been documented in strawberry crops, where generalist predators such as A. nemorum contribute to the control of Spider mite (Tetranychus urticae)^[14] . Prefers lower moist vegetation, especially nettles later in the growing season.^{[citation needed]}

A. nemorum is typically 3–4 mm in length. These bugs have soft elongated flat bodies, with reflective forewings and black pronotum. The legs are mostly orange-brown, with small dark patches close to the tips of the femora. The antennae are mainly orange, with dark tips. In particular, antennal segments I and IV are usually dark, while II and III are pale with dark apices. The front wing is shiny transparent with a distinctive black dot in the center. The membrane shows an hourglass-shaped characteristic black spot at the wing tip. Nymphs of A. nemorum are dark brown or reddish brown.^[10][11]

Anthocoris nemorum is an efficient predator of small arthropods, particularly aphids and Thrips, which makes it an important contributor to pest suppression in agricultural systems . Laboratory and field studies have demonstrated that predation rates vary with temperature, with higher activity observed under warmer conditions^[13]. This species also exhibits adaptive responses to pathogens. For example, individuals can detect and avoid surfaces contaminated with the entomopathogenic fungus Beauveria bassiana, thereby reducing mortality risk ^[15]. Although primarily beneficial, A. nemorum occasionally interacts with humans. Adults may bite when handled, producing a painful but harmless reaction.^{[citation needed]}

Females have a specialized that allows eggs to be laid inside plant tissues which protect them from desiccation and predation.Oviposition behaviour is closely tied to host plants. Females show preferences for laying eggs on apple and pear trees, which aligns with their role in orchard pest management (Ovipositor) ^[12]. Habitat and prey preferences vary among related species, but A. nemorum is consistently associated with environments rich in aphid populations^[6]. The species also exhibits behavioural physiology such as prey switching, which ensures feeding efficiency when preferred prey are scarce.^{[citation needed]}

A. nemorum is widely recognized as a beneficial predator in agricultural systems, where it contributes to the suppression of pest populations such as aphids, psyllid, thrips, mites, and small caterpillars. Its generalist feeding habits allow it to adapt to different prey depending on availability, making it a reliable component of Integrated pest management (IPM) programs ^[2].

In an orchard systems, A. nemorum has been shown to reduce populations of pear psylla (Cacopsylla pyri), a major pest of pear trees, highlighting its role in fruit production^[12]. In cabbage crops, it preys on cabbage aphids (Brevicoryne brassicae) and Diamondback moth larvae (Plutella xylostella), demonstrating its effectiveness in suppressing multiple pest species ^[13]

Environmental factors such as temperature strongly influence predation rates, with warmer conditions increasing feeding efficiency ^[13]. Additionally, A. nemorum can detect and avoid fungal pathogens such as Beauveria bassiana, which enhances its survival and long-term effectiveness as a biological control agent ^[15] .

Habitat and prey preferences vary among Anthocoris species, but A. nemorum is consistently associated with environments rich in aphid populations, reinforcing its value in crop protection^[6] . By reducing reliance on chemical pesticides, the use of A. nemorum in IPM supports sustainable agriculture and minimizes environmental impact. Its ability to overwinter in bark and leaf litter ensures persistence across seasons, providing long-term pest control in managed ecosystems.^{[citation needed]}

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