Two new species of phytoseid mites Euseius ( Acari : Phytoseiidae ) from Kerala , India

Two new species of phytoseiid mites, Euseius pariyarensis sp. nov. and E. curcasae sp. nov., collected from the medicinal plants Saraca indica L. and Jatropha curcas L. respectively, are described from the Kerala State of India.  The morphological features of the two species are described with appropriate illustrations.

was published by Moraes et al. (1986), which included about 1,500 species under 79 genera.The first version of an electronic database of Phytoseiidae prepared by Demite et al. (2014) included 2,436 valid species under 91 genera, of which the genus Euseius contains 219 valid species.Gupta & Karmakar (2015) prepared an updated checklist of Indian phytoseiid mites, which included 211 species.The present paper deals with the description of two new species under the genus Euseius, inhabiting the medicinal plants growing in northern Kerala, India.

Methods
The specimens included in the study were collected from mite-infested leaves of two species of medicinal plants namely, Saraca indica L. and Jatropha curcas L. The collected leaves were examined under a stereo zoom microscope (Magnus -MSZ-TR Trinocular Microscope).The mites wandering on the leaf surface were picked up with a camel hair brush and directly mounted on microscopic slides in Hoyer's medium (Haderson 2001).Systematic position of the species was identified following Gupta (2003) and Chant & McMurtry (2007) and by seeking expert opinion.The setal nomenclature followed Rowel et al. (1978) and Chant & Yoshida-Shaul (1989, 1991).All measurements are given in microns.
Chelicera: 24.5μm long, three teeth on fixed digit and none on movable digit.
Spermatheca: With tubular cervix 20μm long and with bifid atrium.
Peritreme: Terminates anteriorly between j 1 and j 3 .Chelicera: Fixed digit 22μm long with two apical teeth and movable digit with no tooth.Macrosetae on leg IV: genu 37μm (34-38 μm), tibia 35μm (36-37 μm), basitarsus 49μm (47-45 μm).Remarks: The specimen studied resembles E. alstoniae described by Gupta (1975) in dorsal chaetotaxy, structure of spermatheca, and length of macrosetae but differs in the following characters: 1. Dorsal shield longer and wider (368μm, 270μm) than that of E. alstoniae (325μm, 204μm).2. Dorsal shield slightly reticulated on lateral margin of the anterior half, whereas it is smooth anteriorly and rugose posteriorly in E. alstoniae.3.In the new species, seta S 2 shorter than Z 1 , while in E. alstoniae, S 2 noticeably longer than Z 1 .4. In the new species, j 1 30μm (29-31 μm) and j 3 13μm (12-14 μm) long, whereas in E. alstoniae, j 1 almost equal (25-28 μm) in length and j 3 double the length than that of the new species (28-34 μm). 5. Seta JV 5 25μm long in the new species, whereas in E. alstoniae, JV 5 is 44μm.6.The number of teeth on the fixed digit of chelicerae is three in the new species, whereas it is two in E. alstoniae.7.In the new species, the shape of the ventrianal shield is pentagonal and measures 124μm long and 65μm wide, whereas in E. alstoniae, lateral margin of ventrianal shield slightly concave and differs in size (90-100 μm long, 70-80 μm wide).8. Peritreme terminates anteriorly between j 1 and j 3 in the new species, whereas in E. alstoniae, it terminates between j 3 and z 2 This new species resembles E. bambusae described by Ghai & Menon (1967) also in the dorsal chaetotaxy but differs in the following characters: 1. Dorsal shield slightly reticulated along the lateral margin in the new species, whereas in E. bambusae, the entire dorsal shield is gently reticulate.2. In the new species, seta JV 5 22μm long, whereas in E. bambusae it is 38μm long.3. Macrosetae on leg IV genu 37μm (35-39 μm), tibia 35μm (33-37 μm), and tarsus 49μm (47-50 μm) long in the new species, whereas in E. bambusae, genu 52-56 μm, tibia 44--45 μm, and basitarsus 68-72 μm long.4. In the new species, peritreme terminates between j 1 and j 3 , whereas in E. bambusae, peritreme terminates anteriorly between j 3 and z 2 .5. Fixed digit of chelicerae with three apical teeth and movable digit with no tooth in the new species, whereas in E. bambusae, 3-4 apical teeth and one tooth on movable digit.Etymology: The nomenclature of this new species is based on one of the host plants, Jatropha curcas L., from which the specimens were collected.