Eutarsopolipus echinatus, Seeman, 2019

Seeman, Owen D., 2019, Two new species of Australian Eutarsopolipus (Acariformes: Podapolipidae) from Nurus medius (Coleoptera: Carabidae), Zootaxa 4647 (1), pp. 134-153 : 142-148

Eutarsopolipus echinatus sp. nov.

Diagnosis. All life stages: respiratory system absent; tarsus II without solenidion; femur I with two setae (v″ absent); genu I–III lacking setae; claws absent on legs I–III; setae ch, v1, sc1, c1, c2, d, f short, thorn-like. Adult female: gnathosomal length 44–46, width 43–46, cheliceral stylets long, 44–50; seta h absent; tarsi II–III with setae u′ and p′ in proximal position, seta pv′ absent. Larviform adult male: setae v1, sc1, c1, c2, f short, length 2–3; leg setation same as female. Larval female: plates C and D separate; seta h2 long, 33–44.

Type material: 4 females, 1 male, 5 larvae, all ex Nurus medius , as follows. Australia: Queensland. Holotype female, Eungella NP, Mt William, Site 1, 1234 masl, 21.016°S 148.598°E, 14 Nov. 2013, SC 25844, C. Burwell ( QMS 110153, on same slide as paratype larva of E. burwelli QMS 110133). Paratypes : 1 female, 1 male, 1 larva, same data as holotype ( QMS 110154 -56) ; 1 female, Broken River, Eungella NP, 21° 10′ 5″S 148°30′30″E, 17 Nov. 1992 – 15 Apr. 1993, IN7677, G. Monteith, D. Cook, HR# T82045 ( ANIC 52-003933 ) ; 1 female, Eungella NP, Dalrymple Heights , 21° 8′12″S 148°29′30″E, IN7864, 6 Jan. 1973, J. Hammond, HR# T82062 ( QMS 110157) ; 1 female, 4 larvae, Mt Macartney , 20°49′57″S 148°33′7″E, 19 Nov. 1992 – 15 Apr. 1993, IN5936, HR#T82035 (1 female, 1 larva ZMH-A0002399, ZMH-A0002400, 3 larvae QMS 110158 -60); 1 larva, Mt Macartney, same data except, HR# T82039 ( ANIC 52-003934 ) .

Type deposition. Holotype and most paratypes deposited in QM. One female, one larva deposited in ANIC, one female, one larva deposited in ZMH.

Description. Female ( Figs 6–8 , n = 4). Gnathosoma . Length 45 (44–46), width 46 (43–46). Palp length 14 (13–15). Cheliceral stylets 45 (44–50), pharynx width 13 (11–13), dorsal gnathosomal setae (ch) thorn-like, 2 (2–4), ventral setae (su) 7 (7–10), distance between ventral setae (su–su) 17 (17–19).

Idiosoma . Body not to slightly physogastric, ovate. Length 285 (215–305), width 210 (185–275). Respiratory system absent. Dorsal setae v1, sc1, c1, c2, d, f thorn-like. Prodorsal plate length 71 (65–75), with setae v1 6 (6–7), v2 vestigial, sc1 7 (7–8), sc2 32 (31–35); v2 anteromesad sc1. Distance between setae v1–v1 30 (28–35), sc1–sc1 79 (79–86), v1 –sc1 37 (37–40), v2–v2 40 (39–44), sc2–sc2 89 (89–111), sc1–sc2 10 (10–12). Plates C, D, EF, H variously eroded medially, making widths variable. Plate C length 43 (38–43), setae c1 6 (5–6), setae c2 4 (4–5), distance between setae c1–c1 73 (73–94), c1–c2 54 (52–62). Plate D length 24 (24–40), setae d 4 (4–6), d–d 91 (84–93), cupuli ia anteromesad setae d. Plate EF length 30 (26–33), setae f 3 (2–3), f–f 66 (66–85); cupuli im anterolaterad setae f. Plate H length 11 (11–15), width 61 (55–62), setae h absent. Venter: small, thorn-like, 1a minute (minute–1), 2a 3 (2–3), 3a 3 (2–3), 3b 3 (2–3). Alveoli 1b, 2b apparent. Distance between setae 1a–1a 29 (24–28), 2a–2a 41 (30–41).

Legs. Setal counts legs I–III, femur-tarsus: 2-0-5(+ φ)-9(+ ω), 0-0-4-7, 0-0-4-7. Leg I: femur I, d minute, l′ 3 (2–3); tibia I, d 28 (25–28), l′ 5 (4–5), l′′ 1 (1–2), v′ 5 (4–5), v′′ 4 (4–5), φ 7 (7–9); tarsus I, tc′ 10 (9–10), tc′′ 9 (9–10), pl′ 7 (7–10), pl′′ 12 (10–12), pv′ 3 (3–4), pv′′ 3 (3–4), s 6 (6–7), ω 2 (2), p′ 1 (1), u′′ 2 (2–3). Leg II: tibia II, d 8 (8–10), l′ 4 (4–5), v′ 4 (4–5), v′′ 8 (8–12); tarsus II, tc′ 5 (5), tc′′ 25 (23–26), pl′ 17 (17–19), pv′′ 3 (3), u′ 5 (5), u′′ 1 (1–2), p′ 1 (1–2). Leg III: tibia III, d 7 (7–10), l′ 4 (3–4), v′ 4 (4–5), v′′ 7 (7–10); tarsus III, tc′ 5 (5), tc′′ 32 (26–35), pl′ 17 (17–21), pv′′ 2 (2–3), u′ 5 (5), u′′ 1 (1–2), p′ 3 (2–3). Tibia I seta v′ spine-like; tarsus I setae pv′, pv″ s spine–like. Tibia II–III, seta l′ spine-like; tarsi II–III setae u′ spine-like, setae p′, pv″ spine-like. Claws on legs I-III absent.

Larviform adult male ( Fig. 7 ; n = 1). Gnathosoma . Length 33, width 35. Palp length 10. Cheliceral stylets 25, pharynx width 9, ch 2, su 5, su–su 14.

Idiosoma . Length 180, width 155. Dorsal setae v1, sc1, c1, c2, d, f small, thickened to thorn-like. Prodorsal plate length 61, width 130, with setae v1 2, v2 vestigial, sc1 2, sc2 16; v2 anteromesad sc1. Distance between setae v1–v1 16, sc1–sc1 65, v1 –sc 1 28, v2–v2 23, sc2–sc2 69, sc1–sc2 12. Plate CD length 54, width 140, setae c1 3, c2 3, d 2; distance between setae c1–c1 52, c1–c2 36, d–d 39; cupuli ia anteriad setae d. Plate EF divided, each plate length 17, width 37, setae f 2, distance f–f 23; cupuli im anterolaterad setae f. Genital capsule length 23, width 37, setae h minute. Venter: coxal setae minute, alveoli 1b, 2b apparent. Distance between setae 1a–1a 22, 2a–2a 24.

Legs. Setal counts for legs I–III same as female; setal form similar. Leg I: femur I, d minute, l′ 2; tibia I, d 25, l′ 2, l′′ 2, v′ 3, v′′ 5, φ 5, tarsus I, tc′ 11, tc′′ 11, pl′ 5, pl′′ 9, pv′ 3, pv′′ 2, s 3, p′ minute, u′′ 1, ω 2, left tarsus I with additional thorn-like seta between (pv). Leg II: tibia II, d 5, l′ 4, v′ 5, v′′ 9; tarsus II, tc′ 5, tc′′ 16 (possibly broken), pl′ 16, pv′′ 2, u′ 4, p′ 2, u′′ minute. Leg III: tibia III, d 4, l′ 3, v′ 5, v′′ 10; tarsus III, tc′ 5, tc′′ 24, pl′ 16, pv′′ 2, u′ 5, p′ 2, u′′ minute.

Larval female ( Fig. 10 ; n = 5)

Gnathosoma . Length 38–41, width 39–51. Palp length 11–14. Cheliceral stylets 41–46, pharynx width 10–12, ch 1–2, su 4–5, su–su 14–17.

Idiosoma . Length 175–215, width 135–240. Prodorsal plate length 64–69, width 115–135, with setae v1 4–5, v2 vestigial, sc1 4–5, sc2 70–85; v2 anteromesad sc1. Distance between setae v1–v 1 23–26, sc1–sc1 60– 69, v1 –sc 1 31–36, v2–v 2 25–30, sc2–sc2 73–81, sc1–sc 2 15–19. Plate C length 36–43, setae c1 4–5, setae c2 4–5. Plate D length 37–42, width 65–70, setae d 3–4, distance between setae c1–c1 51–56, c1–c2 49–57, d–d 37–41; cupuli ia anteriad setae d, distance ia–d 4–6. Plate EF length 32–40, width 55–65, setae f 2–3, distance f–f 38–41; cupuli im anteriad setae f, distance im–f 5–7. Plate H length 25–35, width 34–40, seta h1 long, ca. 120, seta h2 long, 33–44. Venter: coxal setae minute–1, distance between setae 1a–1a 25–29, 2a–2a 25–30.

Legs. Setal counts for legs I–III same as female; setal form similar. Leg I: femur I, d minute, l′ 2; tibia I, d 40–47, l′ 5–6, l′′ 2–3, v′ 3, v′′ 8–10, φ 6–7; tarsus I, tc′ 10–11, tc′′ 11–12, pl′ 8–10, pl′′ 15–16, pv′ 3, pv′′ 2, s 4–5, p′ 2, u′′ 2, ω 3. Leg II: tibia II, d 7–9, l′ 3–4, v′ 6–8, v′′ 10–15; tarsus II, tc′ 4–5, tc′′ 31–41, pl′ 17–20, pv″ 2, p′ 3, u′ 4, u′′ 2. Leg III: tibia III, d 7–8, l′ 3–4, v′ 6–7, v′′ 10–13; tarsus III, tc′ 5, tc′′ 26–34, pl′ 16–20, pv′′ 2–3, p′ 3, u′ 4–5, u′′ 2.

Etymology. The name echinatus (Latin: prickly, spiny; gender masculine) refers to the spine-like setae on the dorsum.

Differential diagnosis. The short, thorn-like setae are unlike any other species of Eutarsopolipus . This species fits the concept of the pterostichi species group, which is a heterogeneous collection of eight species that requires revision. Members of this group are generally regarded as species that lack both a respiratory system and setae on genu II–III. However, it includes species with or without ambulacral claws and variable femur I and genu I setation, suggesting either homoplasious morphological reductions within this group or that it is polyphyletic. In lacking ambulacral claws on all legs and all genual setae, E. echinatus sp. nov. is similar to E. inermis Regenfuss, 1974 and E. osunaharae Husband and Kurosa, 2012 , which are the only other species of the pterostichi group that share these character states. These species also share the loss of seta v″ on femur I and seta k on tibia I. In addition to the absence of spine-like setae, E. inermis and E. osunaharae also differ in retaining a solenidion on tarsus II and having larvae with fused plates C and D.

Remarks. The species was found cohabiting with E. burwelli on the type host beetle and beetles T82062 and T82039.

The notations for the p′ setae on tarsus II–III are tentative. Species of Eutarsopolipus may present a minute to small, distal seta on the anterior side of the tarsus. When this seta is proximal to the insertion of the spur-like seta u″, I have interpreted it as the retention of seta pv′, as in E. earnshawi (Constantine & Seeman 2013) . When this seta is distal to the insertion of u″, I have designated the seta as p′. In E. echinatus sp. nov., seta u′ is in an unusual proximal position, so according to my interpretation, I have designated the small spine-like anteroventral seta as p′, which is assumed to have migrated ventrally with u′.

Figures

FIGURE 6. Eutarsopolipus echinatus sp. nov., adult female, dorsum.

FIGURE 7. Eutarsopolipus echinatus sp. nov., adult female, venter.

FIGURE 8. Eutarsopolipus echinatus sp. nov., adult female: (A) leg I, dorsal view; (B) tarsus I, ventral view; (C) leg II, dorsal view; (D) leg III, dorsal view.

FIGURE 10. Eutarsopolipus echinatus sp. nov., larval female: (A) dorsum; (B) tarsus I, detail; (C) Plate H (ventral).