Pentamerismus sititoris Beard and Seeman

Beard, Jennifer J., Seeman, Owen D. & Bauchan, Gary R., 2014, Tenuipalpidae (Acari: Trombidiformes) from Casuarinaceae (Fagales), Zootaxa 3778 (1), pp. 1-157 : 89-95

Pentamerismus sititoris Beard and Seeman sp. nov.

( Figs 75–81 )

Type material examined. Holotype female ex. Belah Casuarina cristata (Casuarinaceae) , AUSTRALIA: New South Wales, Newell Highway, approx. 15 km N Moree, 86 km S Goondiwindi, 29°21’20” S 150°00’24” E, 21 August 2007, coll. J.J. Beard and P.I. Forster (QM). Paratypes. 8 females, 1 male, 2 deutonymphs, 2 protonymphs, larva, same data as holotype (QM, ANIC).

Non-type material examined. 5 females, 1 male, 2 deutonymphs, 2 protonymphs, 2 larvae, same data as holotype; 12 females, 10 males, 1 protonymph, 1 larva ex. Casuarina cristata (Casuarinaceae) under scales at tip of needles, AUSTRALIA: New South Wales, nr Lightning Ridge, Castlereagh Highway, 45 km S Hebel, 28°44′43′′S, 148°09’12′′E, 0 6 May 2007, coll. J.J. Beard and P.I. Forster; AUSTRALIA: 1 female, 1 male, same data except Castlereagh Highway, 6.5 km N Lightning Ridge, 29°25′10′′S, 147°53′21′′E (QM, USNM)).

Diagnosis. Dorsal opisthosomal setae f2 present. Palp setal formula 0-0-0-2-3(1), with palp tibial setae l ′PTi and l′′PTi both present. Anterior margin of prodorsal shield with short notch. Dorsal shields with finely reticulate mosaic sculpturing; dorsal setae broadly lanceolate to palmate; lateral margins of opisthosoma coarsely papillate. Posterior ventral setae ag palmate, barbed; setae g1–2 broadly lanceolate, barbed; setae ps1–2 lanceolate, barbed; setae ps3 fine, smooth. Seta 1c absent. Setae d on femora and genua I–II palmate to broadly lanceolate, barbed; seta ev ′ on femora III broadly lanceolate, barbed; setae v ′, v′′ on tibiae III with broad bases, barbed.

FEMALE (n = 28). Dorsum. ( Fig. 75 ) Body measurements: distance between setae v2 -h1 225–255 [250], sc2- sc2 110–120 [120]; other measurements: v2-v2 41 –46 [43], sc1-sc1 83–88 [84], c1-c1 54–63 [63], c2-c2 125–135 [135], c3-c3 170–180 [175], d1-d1 34–40 [40], d2-d2 105–115 [115], d3-d3 150–155 [155], e1- e1 32–39 [39], e2- e2 135–145 [145], e3-e3 120–140 [130], f2-f2 110–115 [115], f3-f3 89–100 [95], h1-h 1 27–32 [30], h2-h2 60–68 [68]. Anterior margin of prodorsal shield with 1 pair of small lobes forming short medial notch (internal depth 7– 11). Dorsal shields with finely reticulate mosaic sculpturing. Lateral cuticle surrounding shields smooth anteriorly, becoming coarsely papillate posteriorly. All dorsal setae barbed; v2, sc1, sc2, c1–3 lanceolate with broadly rounded tips; all other setae broad, rounded. Setal lengths: v 2 23–24 [23], sc 1 23–26 [26], sc 2 25–30 [30], c 1 24–28 [25], c 2 24–28 [28], c 3 21–24 [24], d 1 17–20 [17], d 2 19–26 [20], d 3 19–23 [23], e 1 17 –22 [19], e 2 17 –20 [20], e 3 17 –20 [19], f 2 17–20 [19], f 3 17–21 [17], h 1 17–20 [17], h 2 16–19 [19]. Palps. ( Fig. 75 ) Setal formula 0, 0, 0, 2, 3(1s+2e). Tibial setae, dorsal 7–8 [7] long, ventral 4–5 [4] long; tarsal eupathidia 4 [4], 4–6 [6] long; solenidion 6 [6] long. Venter. ( Fig. 76 a) Cuticle with transverse striae, abruptly becoming longitudinal posterior to cx IV, extending to genital area; fine striae become coarse lateral to genital area. Circular thickening present in metapodal region, ca. 20–24 diameter, rugose-papillate. Setae g1 inserted in more-or-less transverse line with g2, g2 slightly anterior to g1. Genital shield lightly punctate with transverse reticulation posteriorly, margins irregular, ca. 25–35 [25] long, 36–42 [42] wide; anal setae ps1–3 inserted in longitudinal row on anal plates. Coxal setae fine, except 2c lanceolate; setae ag1 palmate, barbed; g1–2, ps1–2 thick, broadly lanceolate, barbed; ps3 fine, smooth. Setal lengths: 1a 40–51 [40], 1b 24–32 [24], 2b 22–28 [24], 2c 14–16 [14], 3a 35–41 [35], 3b 13–19 [13], 4a 32–35 [32], 4b 12–18 [12], ag 1 13–15 [13], g 1 17–18 [17], g 2 16–18 [18], ps 1 12–17 [13], ps 2 12–15 [12], ps 3 7–10 [10]. Spermatheca. ( Fig. 76 b) Spermathecal tube long, narrow, convoluted, 1 Μm wide, ca. 120 long, terminating in membranous sac. Spermatheca vesicle not visible. Genital opening between anal valves and posterior margin of genital shield. Legs. ( Figs 75 , 77 a) Setal formula for legs I–IV (coxae to tarsi) 1-1-3-3-4-9(1), 2-1-3-3-4-9(1), 1-2- 2-1-3-5, 1-1-1-0-3-5. Tarsi I and II each with 1 antiaxial solenidion ω" (ta I 11 [11] long, ta II 10–11 [10] long) and 2 eupathidia pζ'-pζ" (ta I 6–7 [6], 7 [7] long; ta II 6–7 [6], 6 [6] long). Leg setation as in Table 1 except: coxae I without 1c. Setae v' added to tr IV.

MALE (n = 13). Dorsum. ( Fig. 78 ) Body measurements: distance between setae v2 -h1 195–210, sc2-sc2 90– 105; other measurements: v2-v2 32 –35, sc1-sc1 66–79, c1-c1 40–55, c2-c2 96–120, c3-c3 135–155, d1-d 1 24–37, d2-d2 80–106, d3-d3 110–140, e1- e1 34–42, e2-e2 105–130, e3- e3 97–120, f2-f2 87–105, f3-f3 71–90, h1-h 1 25– 27, h2-h2 54–63. Anterior margin of prodorsum with small lobes forming a short median notch (internal depth 7). Prodorsal, mesonotal and pygidial shields with sculpture and dorsal setae similar to female. Setal lengths: v 2 18– 21, sc 1 18–22, sc 2 19–22, c 1 18–20, c 2 19–21, c 3 20–22, d 1 12–13, d 2 16–20, d 3 16–17, e 1 13 –15, e 2 16 –18, e 3 16 –20, f 2 15–16, f 3 14–18, h 1 15–16, h 2 14–16. Palps. ( Fig. 78 ) Palps similar to female. Tibial setae, dorsal 6 long, ventral 5 long; tarsal eupathidia 4–5, 4–6 long; solenidion 5–6 long. Venter. ( Fig. 79 ) Striation similar to female. Posterior opisthosoma with 2 irregular, poorly defined, striated subcircular plates, ca. 25–30 x 30 –45 diameter; g1– 2, ps1–3 on weakly sclerotised anal valves. Coxal setae fine, except 2c lanceolate. Seta ag1 broadly rounded, barbed; g1 lanceolate, barbed; ps1 spine-like, thickened. Setal lengths: 1a 45–65, 1 b 20–23, 2 b 17–19, 2 c 10–13, 3 a 40–42, 3 b 9–12, 4 a 25–27, 4 b 8–12, ag1 12, g 1 12–13, g2 6–7, ps 1 13–15, ps2 6–7, ps3 7. Aedeagus. ( Fig. 79 ) Narrow, sclerotised, tapering to a point, 63–74 long. Membranous duct runs from inside aedeagus,

becoming obscure after 20–55 Μm. Legs. ( Fig. 78 ) Setal formula same as female. Tarsi I and II each with 1 antiaxial solenidion ω" (ta I 13 long, ta II 12 long) and 2 eupathidia pζ'-pζ" (6 long, 5–6 long). Solenidia slightly thicker and longer than in female.

DEUTONYMPH (n = 3). Dorsum. ( Fig. 80 ) Body measurements: distance between setae v2 -h1 215–235, sc2- sc2 105–115; other measurements: v2-v2 34 –39, sc1-sc1 84–89, c1-c1 34–43, c2-c2 110–120, c3-c3 155, d1-d1 38–39, d2-d2 105–115, d3-d3 145–155, e1- e1 32–34, e2-e2 138–143, e3-e3 125–130, f2-f2 110–115, f3-f3 83–90, h1-h 1 31–32, h2-h2 53–60. Anterior margin of prodorsum without medial lobes or notch. Prodorsal shield poorly defined, with oblique-longitudinal striations. Opisthosomal shield absent; transverse striae between setal row C and row D; posterior to setal row D striations become oblique laterally, tending to mosaic-like medially. Lateral setae more elongate than those of adult, slightly concave. Setal lengths: v 2 15–18, sc 1 15–18, sc 2 18–21, c 1 11–17, c 2 18–20, c 3 26–27, d1 15, d 2 24–26, d 3 26–27, e 1 18 –20, e 2 23 –26, e 3 23 –26, f 2 20–24, f 3 22–26, h 1 19–23, h 2 22– 25. Palps. ( Fig. 80 ) Palps similar to adult. Tibial setae, dorsal 6 long, 4 long; tarsal eupathidia 3, 4 long; solenidion 4 long. Venter. Cuticle with transverse striae, becoming coarse behind cx IV; anal setae ps1–3 on weakly defined anal plates. Coxal setae fine, except 2c barbed; setae ag1 thick, barbed. Setal lengths: 1a 27–45, 1 b 12–15, 2 b 11– 16, 2 c 9–11, 3 a 33, 3 b 6–9, 4 a 17–24, 4 b 6–8, ag 1 8–10, g1 11, ps1 3, ps2 4–5, ps3 4–5. Legs. ( Figs 77 b, 80) Setal formula for legs I–IV (coxae to tarsi) 1-1-3-3-4-9(1), 2-1-3-3-4-9(1), 1-2-2-1-3-5, 1-0-1-0-3-5. Tarsi I and II each with 1 antiaxial solenidion ω" (ta I 6–7 long, ta II 5–6 long) and 2 eupathidia pζ'-pζ" (3–4, 4 long). Leg setation as in adult except: tr IV without seta v ′. Setae v' added to tr I–III.

PROTONYMPH (n = 6). Dorsum. Body measurements: distance between setae v2 -h1 165–195, sc2-sc2 78– 90; other measurements: v2-v 2 26–31, sc1-sc1 65–69, c1-c 1 28–32, c2-c2 89–98, c3-c3 130–135, d1-d 1 22–29, d2- d2 84–89, d3-d3 110–125, e1- e 1 18–22, e2-e2 100–110, e3- e3 95–105, f2-f2 76–90, f3-f3 70–73, h1-h 1 19–24, h2- h2 40–50. Anterior margin of prodorsum without medial notch. Prodorsal shield absent, prodorsum with concave striations. Opisthosomal shield absent; transverse striae gradually becoming oblique, tending to convex posteriorly. Setae more elongate than those of adult. Setal lengths: v 2 10–15, sc 1 12–14, sc 2 13–15, c 1 11–12, c 2 14–15, c 3 14– 20, d 1 9–12, d 2 17–21, d 3 25–26, e 1 14 –17, e 2 16 –22, e 3 19 –23, f 2 21–23, f 3 17–21, h 1 18–20, h 2 20–23. Palps. Palps similar to adult. Tibial setae, dorsal 5–6 long, 4 long; tarsal eupathidia both 3 long; solenidion 3–4 long. Venter. Cuticle with transverse striae, becoming coarse behind cx IV. Anal setae ps1–3 on weakly defined anal plates. Coxal setae fine. Setal lengths: 1a 15–17, 1 b 6–7, 2 b 7, 3a 12–23, 3 b 6, ag1 7, ps1 2–3, ps2 2–3, ps3 3. Legs. ( Fig. 81 a) Setal formula for legs I–IV (coxae to tarsi) 1-0-3-1-4-9(1), 1-0-3-1-4-9(1), 1-1-2-1-3-5, 0-0-1-0-3-3. Tarsi I and II each with 1 antiaxial solenidion ω" (4 long) and 2 eupathidia pζ'-pζ" (ta I 4 long; ta II 3 long). Leg setation as in deutonymph except: seta 2c absent; seta 4b absent; tr I–III without seta v ′; ge I–II without seta d, l′′; ta IV without setae tc ′, tc′′. Setae l' added to tr III.

LARVA (n = 3). Dorsum. Body measurements: distance between setae v2 -h1 130–155, sc2-sc2 65–67; other measurements: v2-v 2 22–25, sc1-sc1 50–53, c1-c 1 17–18, c2-c2 68–74, c3-c3 90, d1-d1 12, d2-d2 60, d3-d3 80, e1- e1 7, e2- e2 67, e3- e3 55, f2-f2 45, f3-f3 30, h1-h1 8, h2-h 2 16–38. Anterior margin of prodorsum without medial notch. Prodorsal shield absent, with longitudinal striations becoming broader medially. Opisthosomal shield absent; coarse, irregular transverse striae. Setae with more elongate proportions than those of adult. Setal lengths: v 2 13–15, sc 1 15–18, sc2 13, c1 12, c 2 15–17, c 3 14–17, d 1 17–18, d2 15, d3 15, e1 19, e2 15, e 3 15 –16, f2 16, f3 17, h1 14, h2 15. Palps. ( Fig. 81 c) Palps similar to adult. Tibial setae, dorsal 5–6 long, venter 4–5 long; tarsal eupathidia 3–4, 4 long; solenidion 4 long. Venter. Cuticle with transverse striae, becoming coarse behind cx IV. Anal setae ps1–3 on weakly defined anal plates. Coxal setae fine. Setal lengths: 1a 22–35, 1 b 9–10, 3 a 27–40, ps1 3–4, ps2 3–4, ps3 3–4. Legs. ( Fig. 81 b) Setal formula for legs I–III (coxae to tarsi) 1-0-3-1-4-7(1), 0-0-3-1-4-7(1), 0-0-2-1-3-3. Tarsi I and II each with 1 antiaxial solenidion ω" (ta I 4–6 long, ta II 4–5 long) and 2 eupathidia pζ'- pζ" (ta I 4–5 long; ta II 3–4 long). Leg setation as in protonymph except: seta 2b absent; seta 3b absent; tr I–III nude; ta I–III without seta tc ′, tc′′.

Etymology. The specific name sititoris , is masculine Latin for “one who thirsts”, in reference to the dry habitat in which this species lives.

Remarks. These mites were matt red and found hiding in leaf buds and under leaf scales. Individuals of this species were found in association with Chaudhripalpus costacola and Philippipalpus belah .

Pentamerismus sititoris is similar to P. hicklingorum and P. w a rd o, but can be separated from these two species by the posterior ventral setae g1–2 and ps1–2 being thick, broadly lanceolate and heavily barbed, and setae ag being palmate and strongly barbed (setae g1–2 fine, setiform and weakly barbed, setae ps1 thicker than ps2–3, and setae ag setiform to lanceolate in P. hicklingorum and P. w a rd o).

Figures

FIGURE 75. Pentamerismus sititoris Beard and Seeman, adult female, dorsum with details of palps and legs I – II; solenidion ω " and eupathidia (pζ ′ - pζ ′′) not labelled.

FIGURE 76. Pentamerismus sititoris Beard and Seeman, adult female, a. posterior venter; b. spermatheca.

FIGURE 77. Pentamerismus sititoris Beard and Seeman, a. adult female legs III – IV (right side, ventral aspect); b. deutonymph legs III – IV (right side, ventral aspect).

FIGURE 78. Pentamerismus sititoris Beard and Seeman, adult male, dorsum with details of legs and palps; solenidion ω " and eupathidia (pζ ′ - pζ ′′) not labelled.

FIGURE 79. Pentamerismus sititoris Beard and Seeman, adult male, posterior venter with detail of aedeagus.

FIGURE 80. Pentamerismus sititoris Beard and Seeman, deutonymph, dorsum with details of legs I – II and palps.

FIGURE 81. Pentamerismus sititoris Beard and Seeman, immatures, a. protonymph legs (right side), solenidion ω " and eupathidia (pζ ′ - pζ ′′) not labelled on leg I; b. larva legs (right side), solenidion ω " and eupathidia (pζ ′ - pζ ′′) not labelled on leg I; c. larva palp.