A new species of predatory mite (Acari: Phytoseiidae) from Kerala, India

: Mites belonging to the family Phytoseiidae are renowned biocontrol agents of the plant feeding mites and other phytophagous insects. A survey conducted in different districts of North Kerala revealed a new species of predatory mite under the family Phytoseiidae from Thrissur district. The new species viz., Amblyseius perseani sp. nov. is described with appropriate illustrations.


INTRODUCTION
Phytoseiid mites (Acari: Mesostigmata) constitute a large family of predatory mites.They are fast movers that have extensively exploited the foliage of higher plants (Chant and McMurty, 2007).They are seen mostly feeding on spider mites but can also survive on small insects, nematodes, fungi, honeydew and pollen (McMurty and Croft, 1997;Van Rijin et al., 2002;Nomikou et al., 2003).The importance of the mite family Phytoseiidae in biological and integrated control of injurious plant mite has stimulated taxonomic and ecological work on the group and has led to the discoverey and descriptions of more than 2280 species from the world (Chant and McMurty, 2007;Tixier et al., 2012).
Genus Amblyseius was erected by Berlese in 1914 andZercon obtuses Koch (1839) was designated as its type species.The status of subgenus to genus Amblyseius was given by Chant (1959).Pritchard and Baker (1962) also recognized it as a genus.They divided it into groups and described 20 species in it.Denmark and Muma (1989) revised the genus and described 136 species.
Based on several different characters, genus Amblyseius consists of five different groups and they are the americanus, largoensis, obtusus, pusillus and sundi .The americanus group with z4 longer; the largoensis group with the female ventrianal shield vase shaped or divided into separate ventral and anal shield; the obstusus group with setae z4 shorter ;the pusillus group with seta J2 absent ; and the sundi group with setae Z1 absent (Chant and Mc Murty, 2004).
The genus Amblyseius is further diagnosed in having a lightly sclerotized dorsal shield, female ventrianal shield with variety of shapes, chelicerae with many teeth, leg I, II, III with macrosetae, spermatheca highly variable in form, seta s4, Z4 and Z5 usually greatly elongated with a few exceptions and caudoventral seta ZV3 unstable and absent on a number of species (Chant and McMurty, 2007).
Amblyseius is the largest group of species in the subfamily Amblyseiinae with 367 nominal species and out of them 25 are known from India (Chant and McMurty, 2007).The research work of Chant and Baker (1965), Chant and Hansell (1971), De Leon (1966), Ehara (1959Ehara ( ,1966)), Khan et al., (2000), Muma and Denmark (1970), Schuster and Pritchard (1963), Tuovinen (1993), Wainstein and Arutunjan (1970), on the genus Amblyseius is worth mentioning.Despite of this, there is only a meagre contribution to the acarine fauna from the region of Kerala and the new species described here is a result of the rapid surveys taken to explore the diversity of predatory mites from various districts of Kerala.
The specimens under study were collected from infested parts of economically important plants by beating or shaking methods.Specimens were cleared in lactic acid and permanent slides were prepared using Hoyer Cs medium (Walter and Krantz, 2009).Detailed structural studies and illustrations were made using Wild Leitz GMBH microscope.All measurements are given in microns.The classification system used is that of Chant and McMurty (2007).The setal nomenclature is of Rowell et al. (1978).
All the type specimens are kept in the Department of Zoology, Malabar Christian College but eventually will be transferred to the National Zoological Collection of the Zoological Survey of India, Calicut, Kerala.2. Setae Z5 smaller in this new species as compared to that in phillipsi.

Amblyseius perseani
3. Macrosetae on leg IV being smaller in this new species as it is longer in the case of phillipsi.