Amblyseiulella tibouchina, Molla & Karmakar, 2021

Molla, Md. Iftiar Hossain & Karmakar, Krishna, 2021, Description of five new species of Amblyseiinae (Acari: Phytoseiidae) associated with medicinal plants from the Northern Himalayan Zone of West Bengal, India, Zootaxa 5057 (3), pp. 364-384 : 365-368

Amblyseiulella tibouchina sp. nov.

( Figs 2–6 ; 34–37 )

Diagnosis. Dorsal shield smooth, with marks of densely distributed sigilla on the podosoma and sparsely on opisthosomal area, and with seven pairs of solenostomes; both setae r3 and R1 off shield, with setae J2, S4, and S5 absent. Setae j4, j5, z5, Z1 and j6 small and smooth while setae j1, z2, z4 and R1 relatively long and j3, s4, S2, Z4, Z5 and r3 longer and serrated. Seta J5 minute and serrated. Peritreme extending up to the bases of setae j1. Lateral margin strongly incised at level of setae s4, and with a conspicuous large pore (gd5) associated with setae z5. Calyx of spermatheca bowl-shaped. Sternal shield with three pairs of setae, posterior margin of sternal shield wavy and slightly concave. Fixed digit of chelicera with six teeth and movable digit with two teeth. Ventrianal shield pentagonal, indented laterally with a pair of small circular lyrifissures (gv3) slightly inner side of JV2. Genu, tibia and basitarsus of leg IV each with one smooth and distally knobbed macrosetae, genu II with seven seta.

Female (n = 8). Dorsum ( Fig. 2 ). Idiosomal setal pattern 10A:6D/ JV -3: ZV

Dorsal shield 352 (347–358) long and 193 (188–196) wide, smooth, with an incision at the level of s4 and with marks of sigilla mostly on prodorsum and sparely on opisthosoma, seven pairs of solenostomes (gd1, gd2, gd4, gd5, gd6, gd8 and gd9); 14 pairs of setae on dorsal shield and two pairs of setae on unsclerotised cuticle: j1 35 (33–38), j3 72 (68–75), j4 7 (7–8), j5 8 (8–9), j6 8 (8–9), J5 6 (6–7), z2 21 (19–23), z4 36 (35–38), z5 8 (7–8), Z 1 12 (11–13), Z4 69 (67–71), Z5 86 (84–88), s4 87 (85–89), S2 49 (47–52), r3 56 (54–58), R1 30 (29–32). All setae serrated except j4, j5, z5, Z1 and j6 which short and smooth. Seta J5 minute and serrated. Setae j3, s4, S2, Z4, Z5 and r3 long while setae j1, z2, z4 and R1 medium in length.

Peritreme ( Fig. 2 ). Extending up to the bases of setae j1.

Venter ( Fig. 3 ). All shields smooth. Posterior margin of sternal shield wavy and slightly concave in nature and clearly visible, 69 (66–71) long and 80 (78–82) wide at level of setae ST1–ST3 and ST3–ST3 respectively, with three pairs of setae and two pairs of lyrifissures; one pair of setae ST4 38 (36–39) on metasternal plate with conspicuous lyrifissures. Distances between ST1–ST1 59 (57–62), ST2–ST2 65 (63–68), ST5–ST5 75 (72–77). The genital shield smooth, broad at the base with one pair of setae ST5 31 (29–32) long and narrower towards genital opening, genital flap distinct. Ventrianal shield smooth, pentagonal and vase-shaped, indented lateral margin, 120 (117–123) long, 66 (63–68) wide at level of ZV2 setae and 68 (66–70) at anus level with three pairs of pre-anal setae JV1 21 (20–23), JV2 21 (19–22), ZV2 23 (21–24) and with one pair of relatively small, circular pre-anal pores (gv3) situated sub medially parallel to the setal base of JV2. Distance between pre-anal pores 34 (33–36) and each 3 (2–3) apart from setae JV2. Membrane surrounding ventrianal shield with four pairs of setae ZV1 30 (28–31), ZV3 16 (15–18), JV4 23 (21–24) and JV5 62 (60–64); seta JV5 long and serrated. One pair of metapodal shields 25 (23–26) long.

Chelicera ( Fig. 4 ). Fixed digit 28 (27–30) long, with six teeth and a distinct pilus dentilis, movable digit 31 (29–32) long with two teeth.

Spermatheca ( Fig. 5 ). Calyx of spermatheca bowl-shaped, 4 (3–4) long, 6 (5–6) wide, atrium nodular with minor and major duct distinctly visible.

Legs ( Fig.6 ). Leg IV with three smooth macrosetae with knobbed tips on genu, tibia and basitarsus. Macrosetae of following lengths: Sge IV 36 (34–38), Sti IV 40 (38–43) and St IV 71 (68–74). Chaetotactic formula of genu II 1 2/0 2/1 1 and genu III 2 2/1 2/0 0. Length of leg I 320 (316–327), leg II 300 (296–309), leg III 280 (276–288), and leg IV 390 (382–395).

Type-specimens. Holotype: female (Acarol.lab/ BCKV/8511 /2021) deposited in the NZC, collected from Princess flower (Tibouchina urvilleana Cogn.: Melastomataceae ), at Rishyap: 27 o 10'2"N, 88 o 39'29"E, 2097 m a.s.l., Kalimpong , West Bengal on 16 Nov 2020; seven paratype females (Acarol.lab/ BCKV/8512–8518 /2021) deposited in the BCKV with same collection data as holotype.

Etymology. The specific name tibouchina refers to the type host plant, Tibouchina urvilleana from where the new species were collected.

Remarks. The species Amblyseiulella tibouchina belongs to the heveae species group for the absence of setae S5 and presence of deep incision at lateral margin at the level of s4 ( Chant & McMurtry, 2003). The new species differs widely from the close species A. gapudi Corpuz-Raros, 1995 ; A. yaeyamana Ehara & Amano, 2002 ; A. heveae ( Oudemans, 1930) ; A. paraheveae ( Wu & Ou, 2002) and A. omei ( Wu & Li, 1984) of this group by variation in length of dorsal shield; shape of spermatheca and length of calyx; variation of denticles in fixed and movable digits; shape of ventrianal shield and pattern of posterior margin of sternal shield. All the differences between the new species and the close species are given in Table 1 .

Figures

FIGURES 2–6. Amblyseiulella tibouchina (female). 2. Dorsal view of idiosoma; 3. Ventral view of idiosoma; 4. Chelicera; 5. Spermatheca; 6. Genu, tibia and basitarsus of leg IV.

FIGURES 29–41. 29–33. Amblyseius rishyapensis (female). 29. Dorsal view; 30. Ventrianal shield; 31. Spermatheca; 32. Chelicera; 33. Genu, tibia and basitarsus of leg IV; 34–37. Amblyseiulella tibouchina (female). 34. Dorsal shield; 35. Genu, tibia and basitarsus of leg IV; 36. Chelicera; 37. Spermatheca; 38–41. Okiseius roseus (female). 38. Dorsal view of idiosoma; 39. Spermatheca; 40. Genu, tibia and basitarsus of leg IV; 41. Chelicera.