Neoseiulus californicus (McGregor)

Typhlodromus californicus McGregor 1954: 89.

Amblyseius californicus, Schuster & Pritchard 1963: 271.

Cydnodromus californicus, Athias-Henriot 1977: 64.

Amblyseius (Amblyseius) californicus, Ueckermann & Loots 1988: 150; Ehara et al. 1994: 126.

Neoseiulus californicus, Moraes et al. 1986: 73; Chant & McMurtry 2003a: 21; Moraes et al. 2004a: 109; Chant & McMurtry 2007: 25; Guanilo et al. 2008a: 27, 2008b: 19; sensu Athias-Henriot 1977, Beaulieu & Beard, 2018: 469.

Amblyseius (Neoseiulus) californicus, Ehara & Amano 1998: 33.

Typhlodromus chilenensis Dosse 1958: 55 (synonymy according to Athias-Henriot 1977).

Typhlodromus mungeri McGregor 1954: 92 (synonymy according to Athias-Henriot 1959).

Amblyseius wearnei Schicha 1987: 103 (synonymy according to Tixier et al. 2014).

Neoseiulus californicus belongs to the cucumeris species group of Neoseiulus as the dorsocentral setae are not short relatively to dorsolateral setae. It belongs to the cucumeris species subgroup as spermatheca does not have a stalk between calyx and atrium, the atrium being undifferentiated or nodular and joined directly to calyx (Chant and McMurtry 2003a).

This species is distributed worldwide (see below and Moraes et al. 2004; Demite et al. 2020) and has been introduced in several countries for biological control issues. It is commercialised and released in various crops to control mite pests, especially T. urticae and P. ulmi. It is also naturally found on uncultivated plants or crops such as apple. Many studies deal with its biology. It is a specialized predator, Type 2. Nevertheless, it has characteristics of both specialist and generalist predatory mites (Castagnoli and Simoni 2003). It prefers to feed on spider mites (Gomez-Moya et al. 2009), but can also consume other mite species like tarsonemid mites [Phytonemus pallidus (Banks)] (Easterbrook et al. 2001), small insects such as thrips (Rodriguez-Reina et al. 1992) and even pollen when prey is unavailable (Rhodes and Liburd 2006). It can migrate from grasses to fruit trees or grapevines and vice versa (Auger et al. 1999). It is a specialist predator of T. urticae on annual plants and woody species, and of P. ulmi and various Tetranychus spp. (and perhaps eriophyid mites) on trees and less frequently on grapevines (Auger et al. 1999). N. californicus is well known as a BCA sold in many countries around the world for the management of spider mites in greenhouses but also in outdoor crops such as fruit crops in Europe.

This species was already recorded and mentioned in a Slovenian papers, like Bohinc and Trdan (2015) and Bohinc et al. (2018) but it is the first mention of that species in an international paper for Slovenia.

World distribution: Algeria, Argentina, Australia, Azores, Brazil, Canada, Canary Islands, Chile, Colombia, Cuba, Cyprus, France, Greece, Guadeloupe Island, Guatemala, Italy, Japan, La Réunion Island, Mexico, Morocco, Peru, Portugal, Senegal, Serbia, South Africa, South Korea, Spain, Syria, Taiwan, Tunisia, Turkey, Uruguay, USA, Venezuela.

Specimens examined: 27 ♀♀, 8 ♂♂ and 7 immatures in total. Bukovica (aasl 49 m, lat. 45°54’06”N, long. 13°39’30”E), 22 ♀♀, 7 ♂♂ and 7 immatures on Cucumis sativus L. (Cucurbitaceae), 20/VI/2018; Izola-Pivol (aasl 30 m, lat. 45°32’27”N, long. 13°40’51”E), 1 ♀ on Pyrus communis L. (Rosaceae), 21/VI/2018; Sečovlje (aasl 2 m, lat. 45°28’33”N, long. 13°37’06”E), 2 ♀♀ on C. sativus, 20/VI/2018; Spodnje Škofije-Purissima (aasl 50 m, lat. 45°34’21”N, long. 13°46’31”E), 2 ♀♀ and 1 ♂ on Capsicum annuum L. (Solanaceae), 11/VII/2019.

Remarks: The description and measurements of the adult females collected agree with those provided by Tixier et al. (2008) for specimens of the world, by Ferragut et al. (2010) for specimens from Spain and by Kreiter et al. (2020) for specimens from La Réunion and various regions in the world.