Amblyseius meghalayensis, 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 : 309-311

Amblyseius meghalayensis sp. nov.

( Figs 6–10 ; 63–65)

Following the classification of Chant & McMurtry (2004) the new species Amblyseius meghalayensis sp. nov. belongs to the obtusus species group with the ventrianal shield pentagonal, seta z4 shorter and J2 present; and subgroup obtusus , having calyx of spermatheca with annulated stalk, flaring distally.

Female (n=4). Diagnosis. The new species Amblyseius meghalayensis is distinguished by having dorsum smooth with six pairs of pores, posterior margin of the sternal shield concave, fixed digit of chelicerae with eight teeth, and movable digit with five teeth, leg IV with three pointed macrosetae.

Dorsum ( Fig. 6 ). Dorsal shield 330 (328–332) long and 202 (200–203) wide, smooth, with sigillum mostly on prodorsal area, prodorsum wide, with six pairs of pores (gd2, gd4, gd5, gd6, gd8 and gd9); 17 pairs of setae on dorsal shield and two pair of setae on unsclerotised cuticle: j1 29 (28–30), j3 42 (41–44), j4 5 (4–6), j5 5 (4–6), j6 5 (4–6), J2 5 (4–6), J5 5 (4–6), z2 5 (4–6), z4 5 (4–6), z5 5 (4–6), Z1 8 (7–9), Z4 106 (105–108), Z5 182 (182–184), s4 84 (83–85), S2 8 (8–10), S4 8 (8–10), S5 8 (8–10), r3 14 (13–15), R1 13 (12–14). All setae smooth, setae j1, j3, s4, and Z4 long while seta Z5 longest, and all other setae medium to minute.

Peritreme ( Fig. 6 ). Extending beyond the bases of j1.

Venter ( Figs 7 ; 63–65). Sternal shield nearly square, posterior margin of sternal shield concave, lateral margins of both sides are indented inwardly with a distinct groove at the middle of anterior margin. Sternal shield 66 (65–67) long, and 69 (67–70) wide at the 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 2 5 (25–27) long. Distances between st2 - st2 and st5-st5 62 (61–64) and 69 (68–71) respectively. Genital shield smooth, broad at the base and narrow at genital opening with irregular circular flap that reaches posterior margin of sternal shield. Ventrianal shield smooth, pentagonal 110 (108–111) long, 85 (84–86) wide at level of ZV2 and 56 (54–57) wide at anus level with three pairs of pre-anal setae, JV1 15 (15–18), JV2 15 (15–18), ZV2 15 (15–18) and one pair of pre-anal pores gv3 29 (28–32) apart at the level of JV2. Membrane surrounding ventrianal shield with four pairs of setae ZV1 15 (15–18), ZV3 10 (9–11), JV4 8 (8–10) and JV5 72 (71–74); JV5 long and smooth. Two pairs of metapodal shields present; Primary inguinal sigilla 16 (15–18) long, 5 (4–6) wide, and secondary ones 10 (9–11).

Chelicera ( Fig. 8 ). Fixed digit 39 (38–40) long with eight teeth and movable digit 35 (33–37) long with five teeth.

Spermatheca ( Figs 9 ; 65). Calyx elongated, 15 (14–16) long; annulated distally and broad near atrium, atrium covers almost the width of calyx or incorporated in the basis of calyx, major duct flattened, clearly visible while minor indistinct.

Legs ( Fig. 10 ). The genu, tibia and tarsus of leg IV with pointed macrosetae of following lengths: genu 88 (88–90), tibia 68 (67–70) and tarsus 85 (84–87). Chaetotactic formula of genu II 0 2/2, 1/1 1 and genu III 0 2/1, 1/1 1. Length of leg I 395 (393–398), leg II 315 (314–319), leg III 306 (304–308) and leg IV 355 (352–356). Leg II and III with macrosetae SgeII 50 (48–51), SgeIII 47 (46–50), StiIII 43 (43–45) long.

Type specimens. Holotype: female (Acarol.lab/ BCKV/8374 /20) collected from Cogon grass ( Imperata cylindrica ), at Jaintia Hills: 25°20'31"N, 91°53'19"E, 1496m AMSL, West Jaintia Hills , Meghalaya on 5 th May , 2019 and deposited in the NZC, Zoological Survey of India, Kolkata. Three paratype females (Acarol.lab/ BCKV/8374- 8375 /2019) with same collection data as holotype and deposited in the Acarological laboratory, Department of Entomology , BCKV, Mohanpur, Nadia, West Bengal, India.

Etymology. The specific name meghalayensis refers to the type locality Meghalaya of the new species.

Remarks. Amblyseius meghalayensis is distinguished from all other species of the obtusus sub-group by its unique tubular spermatheca which is annulated distally towards vesicle. However, this new species is close to A. abbasovae Wainstein & Beglyarov, 1971 ; A. isuki Chant & Hansell, 1971 ; A. guntheri McMurtry & Schicha, 1987 ; by having annulated calyx of spermatheca, dorsum smooth, seta Z4 and Z5 very long, leg IV with three setaceous macrosetae. The new species differs from these close species by the setal length, ventrianal shield, number of teeth in fixed and movable digit of chelicerae, annulation pattern of spermatheca, length of leg macrosetae etc. All the differences between the new species and its close species are presented in Table 3 .

Figures

FIGURES 6–10. Amblyseius meghalayensis (female). 6. Dorsal view of idiosoma; 7. Ventral view of idiosoma; 8. Chelicera; 9. Spermatheca; 10. Genu, tibia and basitarsusof leg IV.