Okiseius ramdhuracus, 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 : 371-374

Okiseius ramdhuracus sp. nov.

( Figs 12–16 ; 42–46 )

Diagnosis. Dorsal shield highly sclerotised, sculptured on the podosomal area with seven pairs of solenostomes; both setae r3 and R1 off shield, without a lateral incision in the margin of the dorsal shield posterior to seta R1, with setae J2 and S4 absent. Setae j4, j5, j6, z5 and S5 which small, smooth and with pointed tip while all other setae serrated. Peritreme extending beyond to the base of j1. Calyx of spermatheca short pocular shaped. Sternal shield with three pairs of setae and posterior margin of sternal shield concave. Fixed digit of chelicera with five teeth and movable digit with two backwardly-directed teeth. Ventrianal shield vase-shaped, with one pair of small, circular pre-anal pores (gv3) situated medially equidistant from setae JV2 and PA. Tarsus of leg IV with one rod like macrosetae, genu II with seven setae.

Female (n = 4). Dorsum ( Fig. 12 ). Idiosomal setal pattern 10A: 7E/ JV -3: ZV.

Dorsal shield 341 (339–345) long and 190 (188–193) wide, reticulated, with seven pairs of solenostomes (gd1, gd2, gd4, gd5, gd6, gd8 and gd9); 15 pairs of setae on dorsal shield and two pairs of setae on unsclerotised cuticle: j1 22 (21–24), j3 40 (38–42), j4 14 (13–15), j5 16 (15–17), j6 24 (23–26), J5 5 (5–6), z2 39 (38–41), z4 38 (36–40), z5 20 (19–23), Z1 32 (31–34), Z4 39 (38–41), Z5 58 (56–60), s4 40 (39–42), S2 39 (38–41), S5 17 (16–19), r3 42 (41–44), R1 29 (27–30). All setae serrated except j4, j5, j6, z5 and S5 which smooth and with pointed tip. Setae j3, z2, z4, s4, Z4, S2, r3 long while setae Z5 is the longest and all other setae medium to short in length. Setae J5 minute and serrated.

Peritreme ( Fig. 12 ). Extending beyond to the base of j1.

Venter ( Fig. 13 ). All shields smooth. Sternal shield 64 (63–66) long and 63 (61–64) 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 26 (26–28) on metasternal plate. Posterior margin of sternal shield concave and conspicuously outlined in all specimens. Distances between ST1–ST1 43 (41–45), ST2–ST2 52 (51–54), ST5–ST5 62 (60–64). The genital shield smooth broad at the base with one pair of setae ST5 25 (24–26) long, narrower towards genital opening, genital flap distinct. Ventrianal shield vase-shaped and smooth 116 (114–118) long, 60 (58–61) wide at level of ZV2 setae and 63 (62–65) at anus level with three pairs of pre-anal setae JV1 16 (15–17), JV2 15 (14–16), ZV2 15 (14–16) and with one pair of relatively small, circular pre-anal pores situated medially equidistant from setae JV2 and para anal setae (PA). Distance between pre-anal pores 44 (42–46) and each 15 (14–16) apart from setae JV2, Membrane surrounding ventrianal shield with four pairs of setae ZV1 19 (18–20), ZV3 14 (14–15), JV4 16 (15–17) and JV5 41 (39–42); setae JV5 long and serrated. One pair of metapodal shields 28 (27–30) long.

Chelicera ( Fig. 14 ). Fixed digit 24 (23–26) long, with five teeth and a pilus dentilis, movable digit 27 (25–28) long with two teeth.

Spermatheca ( Fig. 15 ). Calyx of spermatheca short pocular shaped, 6 (5–6) long, atrium crescent shaped at the base of major duct from where distinctly visible minor duct arises.

Legs ( Fig. 16 ). Leg IV with one smooth, rod-like macrosetae, St IV 44 (42–46) long. Chaetotactic formula of genu II 1 2/0 2/0 2 and genu III 0 2/1 2/0 2. Length of leg I 276 (273–381), leg II 251 (248–253), leg III 230 (227–233), and leg IV 326 (322–328).

Type-specimens. Holotype: female (Acarol.lab/BCKV/8523/2021) deposited in the NZC, collected from Datura plant ( Datura metel L.: Solanaceae ), at Ramdhura: 27 o 7’17” N, 88 o 34’1” E, 1514 m a.s.l., Kalimpong, West Bengal on 13 Nov 2020; three paratype females ( Acarol .lab/BCKV/8524–8526/2021) deposited in the BCKV, with same collection data as holotype.

Etymology. The specific name ramdhuracus refers to the type locality of this species “Ramdhura” a village of the Kalimpong district in the state of West Bengal.

Remarks. The species Okiseius ramdhuracus belongs to the maritimus species group, and is close to O. tibetagramins Wu, 1987 , O. wongi Kolodochka & Denmark, 1996 , O. maritimus ( Ehara, 1967b) and O. juglandis ( Wang & Xu, 1985) by the presence of R1 out of the dorsal shield and also for absence of dorso-lateral shield notch below R1. The new species differs from its close species by length and shape of dorsal shield setae, variation in length and shape of macrosetae on leg IV and JV5, and position of pre-anal pores on ventrianal shield. All the differences between the new species and its close species are given in Table 3 .

Figures

FIGURES 12–16. Okiseius ramdhuracus (female). 12. Dorsal view of idiosoma; 13. Ventral view of idiosoma; 14. Chelicera; 15. Spermatheca; 16. Genu, tibia and basitarsus of leg IV.

FIGURES 42–51. 42–46. Okiseius ramdhuracus (female). 42. Dorsal view of idiosoma; 43. Chelicera; 44. Genu, tibia and basitarsus of leg IV; 45. Spermatheca; 46. Ventrianal shield; 47–51. Typhlodromips cinchonai. 47. Dorsal view of idiosoma (female); 48. Genu, tibia and basitarsus of leg IV (female); 49. Chelicera (female); 50. Ventral shields (male); 51. Spermatodactyl (male).