Okiseius jainticus, Kar & Karmakar, 2021

Kar, Anamika & Karmakar, Krishna, 2021, Description of eleven new species of phytoseiid mites (Acari: Mesostigmata) from Meghalaya state, north eastern India, Zootaxa 5068 (3), pp. 301-354 : 320-322

Okiseius jainticus sp. nov.

( Figs 21–25 ; 75–78 )

Female (n=7). Diagnosis. The species Okiseius jainticus sp. nov. belongs to the subgroup maritimus , by having R1 off the dorsal shield. This new species is distiguished from all the six species under this subgroup ( Chant & McMurtry, 2003) by having all setae serrated except j4, j5, j6, J5, and z5 which are smooth and all the setae arise from distinct tubercles, seta S5 serrated, both the setae r3 and R1 are off the dorsal shield and each with a distinct depression at the lateral margin of dorsal shield, one pair of long narrow metapodal shields, fixed digit of chelicerae with six teeth, movable digit with three teeth, leg IV with three distinct macrosetae with bulbous tips. In addition, the genu of leg IV having all setae rod-like except macroseseta which has bulbous tip, tibia and basitarsus of leg IV having rod-like setae but ventral setae are pointed.

Dorsum ( Figs 21 ; 75 ). Dorsal shield 333 (332–335) long and 193 (192–195) wide, strongly reticulated, prodorsum wide, smooth lateral margin with seven pairs of pores (gd1, gd2, gd4, gd5, gd6, gd8 and gd9); 15 pairs of setae on dorsal shield and two pairs of setae on unsclerotised cuticle: j1 26 (25–28), j3 38 (38–40), j4 9 (8–10), j5 9 (8–10), j6 25 (24–25), J5 5 (4–5), z2 34 (33–35), z4 43 (42–45), z5 13 (13–15), Z1 38 (38–41), Z4 50 (49–53), Z5 70 (69–72), s4 48 (46–49), S2 49 (48–50), S5 15 (14–17), r3 41 (39–42), R1 28 (26–29). All setae serrated, except j4, j5, j6, J5 and z5 which are smooth.

Peritreme ( Fig. 21 ). Extending beyond the bases of j1.

Venter ( Figs 22 ; 78 ). All shields smooth. Sternal shield longer than width, posterior margin of sternal shield wavy. Sternal shield 66 (63–67) long and 76 (74–77) wide at level of setae st1 - st3 and st3-st3 respectively, with three pairs of setae and two pairs of poroids; one pair of setae (st4) on unsclerotised membrane 17 (15–18) long and conspicuous poroids on distinct metasternal plate. Distances between st2-st2 59 (58–60), st5-st5 65 (64–68). Genital shield smooth, broad at base and narrow at genital opening with irregular circular flap and almost straight posteriorly. Secondary ones fused anteried form a single pair 42 (40–44) long. Ventrianal shield smooth, pentagonal 105 (103–105) long, 56 (54–57) wide at level of ZV2 and 60 (59–62) wide at anus level with three pairs of pre-anal setae, JV1 14 (13–15), JV2 14 (13–15), ZV2 13 (12–14) and one pair of pre-anal pores gv3 26 (24–27) apart at the level JV2. Membrane surrounding ventrianal shield with four pairs of setae ZV1 18 19 (18–20), ZV3 10 (9–10), JV4 15 (13–15) and JV5 49 (48–50); seta JV5 long and serrated.

Chelicera ( Fig. 23 ). Fixed digit 25 (24–25) long with six teeth and a distinct pilus dentilis, movable digit 25 (24–25) long with three teeth.

Spermatheca ( Figs 24 ; 77 ). Calyx short 10 (7–11) long, arms diverging distally, atrium nodular, minor duct and major duct distinctly visible.

Legs ( Figs 25 ; 76 ). The genu, tibia and tarsus of leg IV with bulbous macrosetae of following lengths: genu 29 (28–30), tibia 24 (23–25) and tarsus 51 (50–53). Chaetotactic formula of genu II 1 2/1. 1/1 1 and genu III 1 1/1. 2/1 1. Length of leg I 282 (280–284), leg II 250 (246–250), leg III 236 (235–238) and leg IV 342 (341–345).

Type specimens. Holotype: female (Acarol.lab/ BCKV/8384 /20) collected from Golden Himalayan raspberry ( Rubus elypticus ), at West Jaintia Hills , Meghalaya 25°21'44"N, 91°52' 40"E, 1933 m AMSL on 1 st May, 2019; and deposited in the NZC, Zoological Survey of India, Kolkata. Six paratype females (Acarol.lab/ BCKV/8385- 8387 /2019) collected from undetermined climber at Mawkdok : 25°24'30"N, 91°46'44"E, 1806 m AMSL, East Khasi Hills , with same data as holotype and deposited in the Acarological Laboratory of BCKV, Mohanpur, Nadia, West Bengal, India.

Etymology. The specific name jainticus refers to the Jaintia Hills, the habitat of the new species.

Remarks. Okiseius jainticus is close to O. maritimus ( Ehara, 1967a) ; O. alniseius Wainstein & Beglyarov, 1972 ; O. juglandis Wang & Xu, 1985 ; O. tibetagramins Wu, 1987 ; O. tribulation Walter, 1999 and Okiseius wongi Denmark & Kolodochka, 1996, by the similar type of dorsal and ventral pattern, presence of depression at level r3, R1 and S5. The new species differs from all these close species by the length of dorsal setae, serration of dorsal setae, number of metapodal shields, denticles on fixed and movable digit of chelicerae, number of rod-like setae on leg IV etc. All the differences between the new species and its close species are presented in Table 6 .

Figures

FIGURES 21–25. Okiseius jaintiacus (female). 21. Dorsal view of idiosoma; 22. Ventral view of idiosoma; 23. Chelicera; 24. Spermatheca; 25. Genu, tibia and basitarsus of leg IV.

FIGURES 75–78. Okiseius jaintiacus (female). 75. Dorsal view of idiosoma; 76. Genu, tibia and basitarsus of leg IV; 77. Spermatheca; 78. Sternal shield; 79–84. Okiseius unisetatus (female). 79. Dorsal anterior view of idiosoma; 80. Dorsal posterior view of idiosoma; 81. Ventrianal shield; 82. Genu, tibia and basitarsus of leg IV; 83. Chelicera; 84. Spermatheca.