Phytoseius ferrum, Kar & Karmakar, 2022

Kar, Anamika & Karmakar, Krishna, 2022, Description of nine new species of phytoseiid mites (Acari: Mesostigmata) from Sikkim, a north eastern States of India, Zootaxa 5182 (3), pp. 201-237 : 221-223

Phytoseius ferrum sp. nov.

( Figs. 31–35 ; 75–78)

Diagnosis. The new species is characterised by dorsum strongly reticulated; ventrianal shield sole shaped with three pairs of preanal setae; fixed digit of chelicerae with two teeth and movable digit with one tooth, leg IV with two rod like macrosetae on tibia and tarsus, all the dorsal leg setae are blade or chopper like.

Description. Female (n = 8). Dorsum ( Fig. 31 ). Dorsal shield 300 (300–308) long and 148 (145–152) wide, strongly reticulated, with six pairs of solenostomes (gd1, gd2, gd4, gd5, gd8 and gd9); poroids are shown in the illustration; 15 pairs of setae on the dorsal shield: j1 28 (26–29), j3 35 (35–38), j4 5 (4–6), j5 5 (4–6), j6 5 (4–6), J5 5 (4–6), z2 20 (20–23), z3 28 (26–29), z4 15 (14–18), z5 5 (4–6), Z4 80 (79–81), Z5 75 (74–80), s4 120 (118–121), s6 75 (75–78), r3 40 (38–41). All setae serrated except the setae j4, j5, j6, and z5 which are smooth and pointed

Peritreme ( Fig. 31 ). Extended beyond the bases of j1.

Venter ( Fig. 32 ). All the shields are smooth. The sternal shield square shaped, posterior margin of sternal shield indistinct. Sternal shield 64 (62–65) long and 75 (74–78) 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) on unsclerotised membrane 21 (20–23) long. Distances between st2-st2 65 (62–66), st5-st5 73 (72–75). Base of genital shield broad, posterior margin little convex with a notch at lateral margin below st5. One pair of metapodal shields visible, genital shield smooth, broad at base and narrow at genital opening with semicircular flap. Ventrianal shield smooth, sole shaped 100 (98–102) long, 32 (31–33) wide at level of ZV2 and 52 (50–54) wide at anus level with three pairs of pre-anal setae, JV1 14 (13–15), JV2 14 (13–15), ZV2 12 (10–12) and one pair of pre-anal pores (gv3) on longitudinal line below JV2 14 (12–15) apart. Membrane surrounding ventrianal shield with three pairs of setae ZV1 15 (15–18), ZV3 9 (8–10), and JV5 55 (53–57); seta JV5 long and serrated.

Chelicera ( Fig. 33 ). Fixed digit 25 (23–26) long with two teeth and movable digit 24 (23–25) long with single tooth.

Spermatheca ( Fig. 34 ). Calyx short 6 (5–8) long, cup shaped with nodular atrium, wide at base of vesicle, minor duct not visible while the major duct long and very distinct.

Leg ( Fig. 35 ). Length of leg I 280 (278–282), leg II 210 (208–212), leg III 210 (208–212) and leg IV 400 (398–403). Chaetotactic formula of genu II 1 2/1 1/1 1 and genu III 1 2/1 2/0 1. The tibia and tarsus of leg IV with spatulated macrosetae enveloped by hyaline cover at the tip. The macrosetae are of following lengths: Sti 50 (50–54) and Sta 30 (28–32). The setae of genu IV and tibia IV are chopper or blade shaped while pointed ventral seta present only one on each of tibia and tarsus.

Type specimens. Holotype female (Acarol.lab/ BCKV/8661 /2021) deposited in the NZC, Zoological Survey of India, Kolkata, collected from wild brinjal ( Solanum torvum ), at Assam Linzey : 27°16’58”N, 88°31’20”E, 1355 m above AMSL, East Sikkim, Sikkim on 30 th March , 2021; 7 paratype females (Acarol.lab/ BCKV/8662-66 /2021) with same collection data as holotype deposited in the Acarological laboratory, Department of Entomology , BCKV, Mohanpur , Nadia , West Bengal, India.

Etymology. The specific name ferrum refers to the “chopper or blade shaped” leg setae of this new species.

Remarks. The new species Phytoseius ferrum sp. nov. is notable from all the species under horridus species group by having blade or chopper like leg setae and also having two pairs of leg macrosetae, genu IV without macrosetae, instead all setae are typically chopper like. However, this new species is close to P. sonunensis Ryu & Ehara, 1993 ; P. nipponicus Ehara, 1962 ; P. neocorniger, Gupta, 1977 ; and P. jujuba Gupta, 1977 , all by having leg IV with two macrosetae but differs from these close species by the length and form of dorsal shield setae, serration of setae z2 and z4, number of metapodal shield, denticles in fixed and movable digit of chelicerae, macrosetae on leg IV and shape of spermatheca. All the differences between the new and close species are given in Table 7 .

Figures

FIGURES 31–35. Phytoseius ferrum (female). 31. Dorsal view of idiosoma; 32. Ventral view of idiosoma; 33. Chelicera; 34. Spermatheca; 35. Genu, tibia and basitarsus of leg IV.