Phytoseiulus persimilis Athias-Henriot, 1957

Kreiter, Serge, Fontaine, Olivier & Payet, Rose-My, 2018, New records of Phytoseiidae (Acari: Mesostigmata) from Mauritius, Acarologia 58 (4), pp. 773-785 : 776

Phytoseiulus persimilis Athias-Henriot

Phytoseiulus persimilis Athias-Henriot, 1957: 347 ; Moraes et al., 1986: 109; Moraes et al.,

2004: 169; Chant & McMurtry, 2006: 20; 2007: 55. Phytoseiulus riegeli Dosse, 1958: 48 (synonymy according to Chant, 1959: 109).

Typhlodromus persimilis, Hirschmann, 1962: 75 .

Phytoseiulus (Phytoseiulus) persimilis, Wainstein, 1962: 17 .

Phytoseiulus tardi ( Lombardini, 1959) : 166 (synonymy according to Kennett & Caltagirone, 1968: 571).

Specimens examined — Cascavelle (20°17’12.98”S, 57°24’25.99”E, alt. 135 m), 14 ?? +

4 ?? + 5 immatures on Solanum lycopersicum L., 28-IX-2017.

Previous Records — Widely distributed in Africa, Australia, Europe, especially Mediterranean countries, South America, and Asia, probably after largely distributed commercial uses in the world, dispersion in the environment in at least some locations and establishment of this species.

Remarks — (tables 2 & 3) — Measurements of the 14 adult females collected in this work ( Table 2 ) agree very well with measurements of the literature, especially with those of Ueckermann et al. (2007) obtained with a great number of specimens (29) from various African countries.

Macrosetae on basitarsus of leg IV are not serrated but macrosetae of genu and tibia are serrated and there is no pre-anal macrosetae on the ventrianal shield. These are key characters of P. persimilis in comparison to the closely related species Phytoseiulus macropilis (Banks) ( Okassa et al. 2010) .

Only few measurements of adult males are available in the literature and consequently measurements of the four males found in Mauritius are of great interest.

Four males and 14 females in a collected population with a sex ratio of nearly 4 females to one male is not exceptional for that species ( Laing 1968).

Phytoseiulus persimilis is a Mediterranean / subtropical predatory mite that is a type

I species, i.e. a specialist predator of the urticae species group of the genus Tetranychus ( McMurtry and Croft 1997; McMurtry et al. 2013). Considerable research has been conducted on this predator–prey interaction (see review by Kostiainen and Hoy 1996), and numerous biological control programs have used P. persimilis against T. urticae on a wide range of ornamental and vegetable crops. Phytoseiulus persimilis was the first greenhouse biological control agents available commercially and it is one of the most successful biological control agents. It can also be used in temperate climates on open-field crops such as strawberries. Optimum conditions are 20-27 °C and relative humidity of 60-90 %. Cooler or warmer temperatures may have a negative effect on reproduction, development and efficiency of this predatory mite. This species is present in Mauritius probably because of its commercial introduction and uses in vegetable and ornamental greenhouses, dispersion of some specimens released and establishment in the environment. This species is actually reared and sold in La Réunion and commercialised in Mascareignes since a long time (Quilici, personal communication).