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The abundance and diversity of phytoseiid mites in the vegetal ground cover of a citrus orchard were surveyed by monthly samplings from October 2008 to July 2009. Six different vegetal cover management methods were studied: herbicide application without mowing (Gly), mowing without herbicide application (PV), mowing with herbicide application (AV), late mowing without herbicide application (LMV), cover crop (Neonotonia wightii, Fabaceae) without herbicide application (PNeo) and cover crop with herbicide application (ANeo). Eleven species were present in the ground cover, with Phytoseius rex and Proprioseiopsis mexicanus as major species. Species richness and densities (1.5 ± 4.5) in the Gly treatment were very low, except for one sample 4 months after herbicide treatment. The AV and PV treatments showed poor diversity and very low mite densities (1.2 ± 2.6 and 1.4 ± 1.5, respectively). The LMV treatment showed the highest diversity and high density of phytoseiid mites (6.9 ± 8.8). The ANeo and PNeo treatments also showed generally high diversity, but with variations in time and exhibited the highest density of phytoseiid mites (13.5 ± 12.7 and 13.4 ± 9.1, respectively). Neonotonia wightii as the cover crop seems to act as a reservoir of phytoseiid mites, sustaining abundant and diverse populations all year round. Some naturally occurring plant species such as Achyranthes aspera, Amaranthus dubius and Eleutheranthera ruderalis could also constitute favourable host plants for Phytoseiidae. Results are discussed in relation to the potential of collected phytoseiid species as candidates for biological control of phytophagous mites on Guadeloupean citrus orchards.

The identity of specimens belonging to the genus Euseius Wainstein, 1962 found on several trees in France is investigated. These specimens are morphologically close to Euseius stipulatus (Athias-Henriot, 1960) except for the shape of the spermatheca and the dorsal shield reticulation. The aim of the present study was to determine if these specimens belong to this latter species and if the shape of the spermatheca could be considered a reliable diagnostic character. Thirty-four characters, including idiosomal seta lengths, were measured and molecular tests (12S rDNA, COI mtDNA) were carried out. Although small, significant differences between populations of Euseius sp. were observed. The morphometric differences between E. stipulatus and Euseius sp. were very small except for the seta z2 and for the length of the ventrianal shield, as well as the length and form of the spermatheca. Molecular analyses support that Euseius sp. and E. stipulatus are two different species. Euseius sp. has been described as a new species to science in another publication under the name Euseius gallicus . Reliability of some morphological characters for species diagnosis is discussed.

Kampimodromus hmiminai McMurtry and Bounfour, 1989 and Kampimodromus adrianae Ferragut and Peña-Estévez, 2003 are two morphogically close species belonging to the family Phytoseiidae. They are the only two species within the genus Kampimodromus Nesbitt, 1951 that bear six solenostomes and a reduced ventrianal shield. Only some characters, such as the idiosomal seta lengths, idiosomal dorsal ornamentation, and setae ornamentation, distinguish them. Kampimodromus hmiminai has being reported from France and Morocco and K. adrianae from the Canary Islands. Our study tests the hypothesis of synonymy between these two species, using morphological measurements and molecular typing (mtDNA, cytochrome C oxidase I (COI)). The differences in idiosomal setae lengths between K. adrianae and K. hmiminai seem to be large enough to support their species status. However, genetic distances between these two species correspond to an intraspecific range of variation. According to the present data, K. adrianae and K. hmiminai could be considered synonyms, with morphologic differentiation as a result of geographic isolation. This result indicates that comparative setal length, seta serration, and dorsal shield ornementation should be used with caution for species differentiation within the genus Kampimodromus .