Tetranychus gloveri Banks, 1900

Tetranychus gloveri Banks, 1900 View in CoL

Tetranychus gloveri Banks, 1900:76 View in CoL .

Tetranychus quinquenychus McGregor, 1914:358 View in CoL . New synonymy.

Tetranychus antillarum Banks, 1917:194 View in CoL . New synonymy.

Septanychus quinquenychus, McGregor, 1920:664 View in CoL . Misidentification.

Septanychus tumidus, Womersley, 1942:87 View in CoL .

Tetranychus gloveri Banks, 1900 View in CoL : Boudreaux, H.B., 1979, 2:395 – 398.

(Figures: 1–9; 10–13; 53–55) Diagnosis: Male: Empodia of leg I claw-like, empodia II- IV with long proximoventral hair, appearing tridigitate with prominent mediodorsal spur. Tarsus I bears 4 tactile setae and 2 solenidia proximal to the proximal duplex setae. Two solenidia are in line with proximal duplex setae. Palpfemur setae d PFe leaf like. Aedeagal knob lacking anterior projection, posterior projection with a pointed tip which forms an angle of 60 o with the shaft, dorsal margin of knob rounded.

Female: Striation pattern between setae e1–f1 forming a diamond-shaped pattern.Striation in the pregenital region longitudinal, oblique and broken medially. Peritreme hook length 30-34. Tarsus I with 4 setae positioned behind proximal duplex setae. Empodia of each leg split into 6 proximoventral hairs with prominent dorsomedian spurs. Spinneret length and width 5–7 x 4–6.

Material examined: 18 females (Acarol. lab/BCKV/4356- 73/56) 12 males (Acarol.lab/BCKV/4374-85/56) collected from Arachis hypogaea L. ( Fabaceae ) Block Seed Farm, Bidhan Chandra Krishi Viswavidyalaya, Jaguli (22° 55’ 36’’ N, 88° 33’ 76’’ E) Nadia, West Bengal, 9 th March, coll. Subhra Samanta.

Female: ( Figures 1-9 View Figures , 53, 54 View Figures ) Dorsum ( Figure 1 View Figures ): Length of the idiosoma 550- 580, width at the level of c setae 398-430, propodosoma with longitudinal striation forms a semicircular lobe. Histerosomal striation transverse medially, between e1-e1 and f1-f1 striation pattern longitudinal, striation between setae e1-f1 forming a diamond-shaped pattern. Length of dorsal setae: v2 84-92, sc1 139-157, sc2 91-115; c1 138-150, c2 126-138, c3 102-115, d1 118-130, d2 121-135, e1 114-127, e2 115-125, f1 103-113, f2 90-101, h2 56-64. Distance between dorsal setae: v2-v2 76-84, v2 -sc1 21-27, sc1–sc2 92-100, sc1-sc1 102-115, sc2- sc2 267-285, c1-c1 80-88, c1-c2 65-71, c2-c3 98-110, c2-c2 214-226, c3-c3 378-390, d1-d1 116-132, d1-d2 68-76, d2-d2 162-180, c1-d1 72-80, c3-d2 98-109, e1-e1 76-84, e1-e2 80- 88, e2-d2 91-101, e2-e2 227-245, f1-f1 67-77, f2-f2 162-175, f1-f2 76-84, f1-d1 174-186, h2- h2 38-42.

Venter ( Figures 2 View Figures , 54 View Figures ): Ventral setae slender, smooth. Lengths: 1a 73-79, 1b 59-70, 1c 76-84, 2b 79-89, 2c 92- 100, 3a 71-81, 3b 74-82, 4a 76-84, 4b 79-90, ag 59-70, g1 32-40, g2 37-43, ps1 15-17, ps2 14-16, h3 47-57. The striation pattern between the intercoxal region is simple and transverse; striation in the pregenital region longitudinal, oblique, and broken medially. Distance between intercoxal setae: 1a -1a 29-35, 3a -3a 79-89, 4a - 4a 84-93, ag -ag 76-84, g1-g1 92-100, g2-g2 102-114, g1-g2 29-35, ps1-ps1 25-31, ps2-ps2 33-39, h3-h3 99-110.

Gnathosoma ( Figures 3-4 View Figures , 53 View Figures ): Stylophore rounded, with only longitudinal striation. Peritreme distally hooked, hook length 28-32; palpfemur, palpgenu with one setae only, palpfemur d PFe 53-61, palpgenu l’’ PGe 32-38, palptibia with three setae and d PTi 23-29, l’ PTi 8-10, l” PTi 11-13 and a claw; palptarsus (length 15-19, wide 14- 18) with three setae a 7-9, b 8-10, c 8-9; one spinneret suζ length 5-7 width 4-6; one solenidion ω 5-6; two eupathidia ul’ζ 7-9, ul”ζ 7-8. Spinneret length is slightly shorter than two eupathidia. The ratio of length and width of the palptarsus is equal.

Leg ( Figures 5-9 View Figures ): leg I length 333-351, leg II length 268- 285, leg III length 270-280, leg IV length 321-339 (from trochanter to tarsus). Setal pattern on leg I–IV coxa 2-2- 1-1, trochanter 1-1-1-1, femur 10-6-4-4, genu 5-5-4-4, tibia 9(1)-7-6-7, tarsus 13(1) +2 duplex setae- 13(1) + 1 duplex setae-9 (1) - 10 (1). Tarsi I with 10 tactile setae, 3 eupathidia, 1 solenidion and 2 sets of proximal duplex setae, 3 tactile setae and 1 solenidion proximal to the proximal duplex setae; tarsi II with 9 tactile setae, 3 eupathidia, 1 solenidion, 1 set of duplex setae, 1 tactile seta adjacent to duplex setae; tarsi III and IV each having 9 tactile setae and 1 solenidion. Empodia of leg I–IV each with a spur and split into 3 pairs of hairlike structures known as proximoventral hairs.

Male: ( Figures 10-13 View Figures , 55 View Figures ). Aedeagus ( Figures 13 View Figures , 55 View Figures ): In the aedeagus knob Anterior projection is absent, posterior projection with a pointed tip, the dorsal margin of the knob is rounded, the main shaft maximum length is 8-10, maximum width is 6-8, maximum neck length 1-2, neck width 2-3, head length 4-6, the axis of the head forming angle with the shaft 60 o.

Leg ( Figures 10, 11 View Figures ): Tarsus I with 10 tactile setae, 3 solenidia, 3 eupathidia, and 2 sets of duplex setae. Tarsus I bears 4 tactile setae and 2 solenidia proximal to the proximal duplex setae. 2 solenidia are in line with proximal duplex setae. Tibia I with 4 solenidia, and 9 tactile setae. Tarsus II with 10 tactile setae, 1 solenidion, 3 eupathidia, and 1 set of duplex setae. Tibia II with 7 tactile setae. Empodia split with a prominent spur.

Gnathosoma ( Figure 12 View Figures ): Palpal setation from femur to tibia d PFe 8-10, l’’ PGe 20-24, d PTi 15-19, l’ PTi 9-11, l” PTi 11-13. Palpfemur seta d PFe modified into a leaflike structure, palptarsus length 10-12, wide 8-10; palptarsus with 3 setae a 7-9, b 6-8, c 7-9, one spinneret suζ (length 5-7, wide 2-3), one solenidion ω 5-7 and two eupathidia ul’ζ 5-6, ul”ζ 6-7. Spinneret length and width ratio 2:1.

Remarks: This species was described by Banks, 1900 from the United States, on Gossypium sp. We have identified the same species Tetranychus gloveri Banks, 1900 from Arachis hypogaea L. ( Fabaceae ) by comparing the structure of the aedeagus, tarsus of leg I and II mainly the number of setae proximal to the proximal duplex setae, and length of the hook of the peritreme, pregenital striation pattern of female and shape of dorsal palp femoral setae of male. Seeman and Beard, 2011 stated that 1–3 tactile setae overlap with the socket of proximal duplex setae and peritreme hook length 21–27 but here 4 setae proximal to the proximal duplex setae and peritreme hook length 28–32 of females. This species is reported for the first time infesting groundnuts from India.