Phytoseiidae (Acari: Mesostigmata) from the Atlantic Forest in Rio de Janeiro, Brazil, with complementary description of Amblyseius impeltatus Denmark & Muma

Phytoseiid mites (Acari: Phytoseiidae) have been largely used for the biological control of arthropod pests. However, information on the phytoseiid fauna associated with plants of the Rio de Janeiro State, Brazil is still scanty. Surveys were carried out in two areas of Atlantic Forest in Rio de Janeiro State – Jaguanum island and Paraty. We report 11 species of seven genera from all three subfamilies. A complementary re-description is provided for Amblyseius impeltatus Denmark & Muma, 1973 and measurements are provided for ten other species.


INTRODUCTION
The Atlantic Forest occupies mainly the East coast of Brazil, but also parts of Argentina and Paraguay. In Brazil, it covers more than 1 million km² (MMA, 2015). Due to the high degree of endemism and the exceptional loss of original habitat, the Atlantic Forest is considered a hotspot and a world priority conservation area (Myers et al., 2000;Rezende et al., 2018). About 900 mite (Acari) species have been registered in this biome, belonging to 124 families of both Acariformes and Parasitiformes (Giupponi et al., 2017).
The aim of this study was to survey the phytoseiid fauna associated with some native and cultivated plants from Rio de Janeiro state.

MATERIAL AND METHODS
This study was conducted in two areas of the Atlantic Forest in the state of Rio de Janeiro, Brazil: Jaguanum Island (22°59′28″S, 43°55′25″W) and Paraty (23°13′30″S, 44°46′35″W). In each area, native and cultivated plants were sampled, in April ISSN On-Line: 1807-0205 ISSN Printed: 0031-1049 ISNI: 0000-0004-0384-1825 of 2007 (Jaguanum Island) and July of 2008 (Paraty). Specimens were mounted in Hoyer's medium; under "Material examined", we list the locality, specimens collected, host plant and collection date. The illustrations were accomplished using a drawing tube attached to an optic microscope equipped with phase contrast (Leica DM 2500). All measurements are given in micrometres (μm); each measurement corresponds to the mean for the stated number of individuals, followed by the respective range (min-max) in parentheses. The setal nomenclature adopted were those of Lindquist & Evans (1965) and Lindquist (1994), as adapted for Phytoseiidae by Rowell et al. (1978) for the dorsum; and by Chant & Yoshida-Shaul (1991) for the venter. Numbers of teeth on the fixed and movable cheliceral digits do not include the respective apical teeth.

RESULTS AND DISCUSSION
Eleven phytoseiid species belonging to seven genera from three subfamilies were found. A complementary redescription for Amblyseius impeltatus Denmark & Muma, 1973 is provided. Morphological information for the other species is given in Table 1.

Peritreme:
Extending forward to level of j1.
Peritreme: Extending forward to the level of j1.
not showing a distinct atrium and both major and minor ducts (Denmark & Muma, 1973, fig. 15). Subsequently, in a revision of genus Amblyseius, the spermatheca was modified to a stockier shape, with both ducts represented, but with a distinct nodular atrium (Denmark & Muma, 1989, fig. 477). In our specimens, however, the spermatheca had a bell-shaped calyx and an indistinct atrium, indistinguishable from the major duct (Figs. 4, 8).
Micrograph examination of the holotype species (Fig. 8) has revealed the shape of spermatheca matches with the structure described above in our specimens, and do not correspond the previous two illustrations. In addition, all setae on leg IV are herein illustrated on genu (7), tibia (6) and basitarsus (4), while some of the ventral setae were not represented in those previous works.

Amblyseius operculatus
Two species found in this study, T. cananeiensis and P. marumbus, have been found only in the Atlantic Forest so far, suggesting they might be endemic to this biome. Others, like Amblyseius largoensis, Euseius alatus, Iphiseiodes zuluagai, and Proprioseiopsis dominigos, all reported herein, are also frequently registered in several agricultural crops in other localities and biomes in Brazil, indicating phytoseiids from the Atlantic Forest may also migrate to nearby crops and act as natural enemies of pest mites. This reinforces the idea of the native vegetation working as reservoirs of phytoseiids as suggested by previous authors (Tixier et al., 2000;Demite & Feres, 2005, 2008Lofego & Moraes, 2006;Castro & Moraes, 2007Demite et al., 2013;Rezende et al., 2014). Phytoseiids have a major role in ecosystems, regulating phytophagous mite populations in natural environments and agroecosystems (Demite et al., 2013;Lofego & Moraes, 2006). Surveying natural vegetation areas provides a clearer picture of the real diversity of these organisms, also contributing to understand the structure of mite communities and the species turnover between natural vegetation and adjacent crops.  Cavalcante, A.C.C. et al.: Phytoseiidae from Atlantic Forest, Rio de Janeiro Pap. Avulsos Zool., 2021;v.61: e20216198 5/7