Mixonychus ( Bakerina ) aculus (Chaudhri)

Khan, Eid Muhammad, Kamran, Muhammad & Alatawi, Fahad Jaber, 2019, A new species and new records of Tetranychidae (Acari: Trombidiformes) from Saudi Arabia, with a key to world species of Mixonychus Ryke and Meyer, Acarologia 59 (4), pp. 492-506 : 498-499

Mixonychus ( Bakerina) aculus (Chaudhri)

Bakerina aculus Chaudhri, 1971: 197−199 .

Re−description of adult female (n = 6)

( Figures 5−8 )

Idiosoma oval—Length of body (excluding gnathosoma) 340−353, (including gnathosoma) 407−428, width of idiosoma at the level of setae c series 202−215.

Dorsum ( Figures 5 A-C) — Prodorsum bearing 3 pairs of lanceolate, finely barbed setae with blunt tips ( v2, sc1, sc2). Propodosoma dorsomedially with lobed striae forming a strong reticulate pattern medially, with longitudinal laterally. Hysterosoma with 10 pairs of setae ( c1−3, d1−2, e1−2, f1−2, h1), similar in shape to prodorsal setae. Opisthosoma medially with widely separated, lobed, transverse striae, laterally longitudinal to irregular. Dorsal idiosomal setae narrowly lanceolate, finely barbed ( Figure 5C ), just reaching the bases of setae next consecutive row, except setae c1 slightly shorter than distance to next setal row. Striae with irregularly shaped lobes. Length of dorsal body setae: v2 38−43, sc1 49−53, sc2 36−42, c1 37−46, c2 41−47, c3 40−45, d1 40−46, d2 44−50, e1 44 −49, e2 49 −53, f1 47−52, f2 38−41,

h1 44−48; distance between dorsal setae: v2−v2 48−53, sc1−sc1 60−65, sc2−sc2 135−145, v2−sc1 20−22, c1−c1 50−53, c2−c2 95−100, c3−c3 178−190, d1−d1 42−46, d2−d2 106−117, e1− e1 33−39, e2−e2 92−99, f1−f1 44−47, f2−f2 70−77, h1−h1 15−16, v2−sc1 20−25, sc1−sc2 60−65, sc2−c3 50−56, sc2−c2 40−47, sc2−c1 53−59, c1−c2 19−23, c2−c3 48−54, c3−d2 51−55, c1−d1 49−52, c2−d2 54−59, d1− e1 45−50, d1−d2 31−35, d2− e2 49−53, d2− e1 46−50, e1−f1 46−53, e1− e2 32−36, e2−f2 62−68, f1−h1 40−47, f1−f2 25−27, f2−h1 33−38.

Venter ( Figure 6 ) — Idiosoma ventrally with transverse striations from setae 1a to 4a, oblique or longitudinal in pre-genital area; striations on venter without lobes; length of intercoxal and coxae setae, setae on coxae III and IV are serrate: 1a 43−47, 3a 41−44, 4a 31−34, 1b 51−55, 1c 33−37, 2b 41−46, 2c 19−23, 3b 27−30, 4b 30−34; distance between inter-coxal and coxae setae: 1a−1a 31−35, 1b−1c 10−12, 2b−2c 18−20, 3a−3a 50−55, 4a−4a 60−65, 1a−3a 81−88, 3a−4a 40−45, 4a−ag 47−52; aggenital setae: ag 33−37, ag−ag 42−49; two pairs of genital setae: g1 27−31, g2 24−26, g1−g1 28−30, g2−g2 46−53, g1−g2 14−16, ag−g1 20−22, ag−g2 27−29; two pairs of anal setae: ps1 11−13, ps2 10−12, ps1−ps2 11−13, ps1−ps1 15−17, ps2−ps2 16−18; para anal setae two pairs: h2 15−17, h3 16−18, h2−h2 10−12, h2−h3 33−38.

Gnathosoma ( Figure 7 ) — Ventral infracapitular setae m 35−39, m −m 19−21. Palp femur

and genu each with one seta, d 32−35, l” 23−25; palp tibia with three setae, d 20−22, l” 17−19,

l’ 15−16 and a palp tibial claw; palp tarsus 14 long, 11 wide, with three simple setae a 8−10, b 9−10, c 10−12, three eupathidia suζ 5−6, ul”ζ = ul’ζ 7−9, a solenidion ω 11 long; peritremes terminating in hooked; terminal sensillum of palp tarsus conical, long, pointed about 3 time long as wide to the base.

Legs ( Figures 8 A-D) — Length of legs I−IV (without coxae): 216−230, 165−180, 186−199, 224−240, respectively; leg I: trochanter 13−16, femur 75−83, genu 35−38, tibia 52−55, tarsus

40−45; leg II: trochanter 10−12, femur 55−59, genu 31−34, tibia 30−35, tarsus 38−44; leg III: trochanter 25−28, femur 49−53, genu 31−35, tibia 40−45, tarsus 45−48; leg IV: trochanter

20−22, femur 61−65, genu 35−39, tibia 50−55, tarsi 56−60; legs chaetotaxy on I−IV (solenidia

in parenthesis): coxae; 2−2−1−1, trochanter 1−1−1−1; femora 8/7−6−4−4/3; genua 5−5−3−3;

tibiae 9(1ω)−7−6−7; tarsus 11(3ζ, 2ω)−9 (3ζ, 2ω)−8(1ω)−8(1ω).

Male and immature stages Unknown.

Material examined — Four females, Prosopis juliflora (Fabaceae) (native to Mexico,

South America, and the Caribbean), Alhasa 27°55.0143ʹN, 047°66.8970’E, 21 April 2018,

coll. M. Kamran, J. H. Mirza and H. M. Saqib. Four females (KSMA-ARL-19/16-20)

have been deposited at King Saud University Museum of Arthropods ( KSMA, Acarology section), Department of Plant Protection, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia.

Distribution — Pakistan ( Chaudhri, 1971) and SA in present study.

Known hosts — Senegalia modesta (syn. Acacia modesta , Mimosaceae ) (native to

India, Pakistan and Afghanistan), Albizia lebbeck ( paratypes host, Mimosaceae ) (native

to Indomalay region, Papua New Guinea and northern Australia), Platycladus orientalis (Cupressaceae) (native to Korea and northern China), Salvadora oleoides (Salvadoraceae) ( paratypes host; native to India, Pakistan and southern Iran), Vachellia nilotica (syn. Acacia arabica ) ( Mimosaceae ) holotype host (native to Africa, Middle East and India) ( Chaudhri, 1971; Chaudhri et al., 1974).

Remarks — We could not find the type specimens of M. ( B.) aculus from the depository. The specimens of M. ( B.) aculus collected from Saudi Arabia are morphologically similar to the original description except minor differences in length of dorsal and ventral body setae; v2 38−43 vs. 42, sc1 49−53 vs. 57 sc2 36−42 vs. 47, c1 37−46 vs. 44, c2 41−47 vs. 47 d1 40−46 vs. 52, d2 44−50 vs. 49, e1 44 −49 vs. 52, e2 49 −53 vs. 49, f1 47−52 vs. 52, f2 38−41 vs. 47, h1 44−48 vs. 49; 1a 43−47 vs. 39, 3a 41−44 vs. 42, 4a 31−34 vs. 36 and solenidia on both tarsi III and IV 10−12 vs. 16 in original description.

Figures

Figure 5 Mixonychus (Bakerina) aculus (Chaudhri), adult female: A, B – Dorsum; C – Dorsal seta. Scalebar A, B = 100μζ.

Figure 6 Mixonychus (Bakerina) aculus (Chaudhri), adult female: Venter. Scalebar = 100μζ.

Figure 7 Mixonychus (Bakerina) aculus (Chaudhri), adult female: Palp. Scalebar = 50 μζ.

Figure 8 Mixonychus (Bakerina) aculus (Chaudhri), adult female: A – Leg I: B – Leg II; C – Leg III; D – Leg IV. Scalebar A-D = 100 μζ.