Eutarsopolipus tripodus, Seeman & Katlav, 2024

Seeman, Owen D. & Katlav, Alihan, 2024, Podapolipid mites (Acari: Heterostigmata): key to genera, biogeographical history and description of four new Australian species of Eutarsopolipus, Zootaxa 5448 (3), pp. 301-347 : 325-330

Eutarsopolipus tripodus sp. nov.

( Figs 11–14 , 3C , 6C , 9C )

Diagnosis. All life stages: Solenidion present on tarsus II, minute. Female and larva: legs I–III femora 3-0-0 (with vʺ on femur I, rarely absent or asymmetrically absent); genua 2-1-1 (with l″ on genu I). Female: Plate H present, seta h 26–41. Male: genital capsule elongate, about as long as leg III; opisthonotal setae developed; leg setation same as female. Larva: seta h2 flagellate, length 140.

Type material. All ex Notolestus sulcipennis (Macleay) . Holotype female ( QMS 117020 ). Tweed Lookout, Wiangaree SF , 28°23′14″, S 153°06′33″E, 27 Dec 1974 – 23 Mar 1975, G. & S.R. Monteith, rainforest, IN5350, HR# T56958 . Paratypes. 16 females, 7 males, 1 larva, as follows. 12 females ( QMS 117021-29 , ANIC, ZMH), 7 males ( QMS 117034-36 , ANIC, ZMH), 1 larva ( QMS 117037 ), same data as holotype . 2 females ( QMS 117030- 31 ), Whian Whian SF, via Dunoon , 28°38′25″ S, 153°20′01″E, 27 Dec 1974 – 23 Mar 1975, G. & S. R. Monteith, rainforest, IN5354, HR# T56959 . 1 female ( QMS 117032 ), Tullawallal, Binna Burra , 28°12′36″S, 153°11′12″E, 9 Jan–6 Apr 1995, G. Monteith, IN599, HR# T89219 . 1 female ( QMS 117033 ), O’Reilly’s Guesthouse , Lamington NP, 28°13′32″ S, 153°07′35″E, 28 Sep 1975 – 31 Jan 1976, G. & S. R. Monteith, rainforest, IN5474, HR#56986 . All in QM except 1 female and 1 male each in ANIC and ZMH.

Description. FEMALE ( Figs 11–12 , 3C; n = 17). Gnathosoma . Length 135 (135–145), width 150 (140–150). Palp without dorsal tibial seta. Cheliceral stylets 150 (150–160), ch 51 (50–60), su 50 (39–52).

Idiosoma ( Figs 11 , 3C ). Length 640 (600–760), width 510 (460–625), bigger specimens only slightly swollen, body ovate. Prodorsal plate with setae v1 12 (11–13), v2 alveolar remnant anteriad or anterolaterad sc1, sc1 18 (14–15), sc2 86 (100–130). Distance between setae v1–v1 130 (110–130), sc1–sc1 unmeasurable (145–170), v1–sc1 unmeasurable (54–65), v2–v2 unmeasurable (140–145), sc2–sc2 unmeasurable (240–270), sc1–sc2 77 (68–83). Plate C setae c1 19 (16–19), setae c2 20 (15–25; asymmetrically 42 in specimen 4), distance between setae c1–c1 160 (150–210). Plate D setae d 17 (15–18), d–d 250 (260–300), cupuli ia mesad d. Plate EF setae f 18 (16–20), f–f 245 (225–250), cupuli im anterolaterad f. Plate H divided, setae h1 25 (26–41). Venter: coxisterna 1–2 moderately well defined, coxisterna 3 poorly defined; apodemes 1, 2 and appr well defined, apodemes 2 weakly connected with appr, sejugal apodeme absent, apodemes 3–4 well defined. Coxal setae ( Fig. 3C ) thickened, 1a 10 (8–10), 2a 11 (9–11), 3a 10 (8–10), 3b 12 (9–13). Alveoli of 1b, 2b present. Specimen number 3 with an asymmetrical additional seta 2a.

Legs ( Fig. 12 ). Setal counts legs I–III, femur-tarsus: 2/3-2-6(+ φ)-8(+ ω), 0-1-4-7(+ ω), 0-1-4-7. Leg I. Femur I, d minute (m–2), l′ minute (m–2), v″ absent in holotype (but usually present: length 21–30 in specimen numbers 2–11, 13, 16, 17, 18 asymmetrical in 12,14); genu, l′ minute (m), l″ 2 (2–3); tibia, d 88 (85–95), l′ 9 (7–13), l″ 24 (18–25), v′ 14 (13–17), v″ 20 (16–22), k 2 (m–2), φ 14 (11–13) baculiform; tarsus, tc′ 18 (18–20), tc″ 18 (16–18), pl′ 16 (17–22), pl″ 26 (22–28), pv′ 7 (7–8), pv″ 6 (6–9), ω 7 (7–8) clavate, s 9 (8–10), u′′ 2 (2), p′ not evident. Leg II. Genu, l′ 15 (15–17); tibia, d 95 (80–100), l′ 28 (21–30), v′ 21 (19–32), v″ 40 (35–52); tarsus, tc′ 4 (4–5), tc ″ 6 (5–6), pl ″ 100 (75–100), pvʹ 11 (11–17), pv″ 16 (15–20), ω minute (m), u′ 10 (10–11), u′′ 9 (9–12). Leg III. Genu, l′ 10 (9–11); tibia, d 46 (45–70), l′ 26 (15–25), v′ 26 (20–25), v″ 33 (30–35); tarsus, tc′ 6 (4–6), tc ″ 6 (5–6), pl ″ 100 (92–23), u′ 10 (9–11), pvʹ 9 (8–12), pv″ 12 (14–18), u′′ 9 (7–11). Claws on legs I–III small.

Modified setae: genu I with seta l″ small, slightly thickened; tibia I seta k blunt, nubbin-like; tarsus I with seta u″ small, slightly thickened; tarsus I seta s and tarsi II–III setae tcʺ and u′ thickened, large, spine-like, u′ bifid.

MALE ( Figs 13 , 6C; n = 8). Gnathosoma . Length 46–56, width 45–53. Cheliceral stylets 28–30, ch 13–16, su 9–12.

Idiosoma ( Fig. 13 , 6C ). Length 230–280, width 160–205. Prodorsal plate with setae v1 5–6, v2 alveolar remnant, sc1 7–9, sc2 65–90. Distance between setae v1–v1 40–45, sc1–sc1 58–66, v1–sc1 24–31, v2–v2 52–58, sc2–sc2 77–92, sc1–sc2 22–36. Plate CD setae c1 10–13, c2 10–11, d 10–11, distance between setae c1–c1 47–52, c1–c2 48–61, d–d 65–81; cupuli ia anteriad to anteromesad setae d. Plate EF with setae f 6–8, distance f–f 46–59; cupuli im anterolaterad setae f. Genital capsule length 68–84, width 36–51, setae h vestigial. Venter: Apodemes 1, 2 and appr well defined, apodemes 2 fused with appr, sejugal apodeme absent, apodemes 3–4 well defined. Coxal setae ( Fig. 6C ) slightly thickened, 1a 3–4, 2a 4–6, 3a 5–6 (asymmetrically absent in specimen 6), 3b 5–8.

Legs ( Fig. 13 ). Setal counts legs I–III, femur-tarsus: 2-2-6(+ φ)-8(+ ω), 0-0/1-4-6(+ ω), 0-0-4-6. Compared to female:Femur I seta v″ absent(asymmetrically present in specimen #7, 6 long; seta l′ lacking on genu II (asymmetrical in drawn specimen and specimens 4, 8) and genu III. Leg I. Femur, d minute, l′ minute; genu I, l′ minute, l″ minute; tibia, d 55–68, l′ 3–4, l″ 6–7, v ′ 3–6, v ″ 11–17, k 1–2, φ 7–8 baculiform; tarsus, tc′ 13–15, tc″ 14–15, pl′ 6–8, pl″ 11–20, pv ′ 2–3, pv″ 3–4, ω 4–5 digitiform, s 5–6, u ′′ 1–2. Leg II. Genu, l′ 3–4 (when present); tibia, d 36–53, l′ 6–7, v′ 10–14, v″ 16–20; tarsus, tc′ 3–4, tc ″ 3, pl ″ 24–35, pvʹ minute, pv″ 4–6, ω minute, u′ 5–6, u ′′ 2–3. Leg III. Tibia, d 30–37, l′ 7–9, v′ 10–11, v″ 13–14; tarsus, tc′ 2–3, tc ″ 3, pl ″ 30–32, pvʹ minute, pv″ 5–6, u ′ 5–6, u ′′ 1–2. Claws on leg II–III rudimentary or absent.

Modified setae: similar to female except—genu I seta l″ minute; tibia I seta lʹ small, slightly spined; tarsus I with seta u″ smaller, slender; tarsi II–III with tcʹ smaller, spine-like.

LARVAL FEMALE ( Figs 14 , 9C; n = 1). Gnathosoma . Length 95, width 105. Cheliceral stylets 85, ch 47, ventral setae su 23.

Idiosoma ( Figs 14 , 9C ). Length 480, width 315. Prodorsal plate with setae v1 10, v2 alveolar remnant, sc1 13, sc2 150. Distance between setae v1–v1 88, sc1–sc1 105, v1–sc1 52, v2–v2 105, sc2–sc2 160, sc1–sc2 56. Plates C and D completely separate. Plate C setae c1 19, setae c2 17, distance between setae c1–c1 94. Plate D setae d 20, d–d 135, cupuli ia anteromesad d. Plate EF setae f 24, f–f 105, cupuli im anteriad to anterolaterad f. Plate H narrow, 26 wide, 75 long, bearing setae h1 ca. 230, h2 ca. 140. Venter: coxisterna 1–3 membranous; apodemes 1, 2 and appr well defined, apodemes 2 fused with appr, sejugal apodeme absent, apodemes 3–4 well defined. Coxal setae ( Fig. 9C ) slightly thickened, 1a 6, 2a 8, 3a 6, 3b 10. Alveoli of 1b, 2b present.

Legs ( Fig. 14 ). Setal counts legs I–III, femur-tarsus: 3-2-6(+ φ)-8(+ ω), 0-1-4-6(+ ω), 0-1-4-6. Leg I. Femur, d minute, l′ minute, v″ 25; genu, l′ 2, l″ 2; tibia, d 125, l′ 10, l″ 18, v′ 11, v″ 16, k 4, φ 13 baculiform; tarsus, tc′ 16, tc″ 16, pl′ 15, pl″ 26, pv′ 4, pv″ 5, ω 5 clavate, s 6, u′′ 2, p′ absent. Leg II. Genu, l′ 10; tibia, d 105, l′ 16, v′ 19, v″ 40; tarsus, tc′ 4, tc ″ 4, pl ″ 90, pv″ 9, ω minute, u′ 6, u′′ minute. Leg III. Genu, l′ 9; tibia, d 100, l′ 16, v′ 21, v″ 40; tarsus, tc′ 4, tc ″ 4, pl ″ 80, u′ 7, pv″ 4, u′′ minute.

Leg I with single bifid claw; legs II–III claws rudimentary.

Modified setae: similar to female except—genu I with setae lʹ and l″ thin, spine-like; tibia I seta k thin, spine-like; tarsi II–III with tcʹ thin, spine-like.

Differential diagnosis. The retention of the solenidion on tarsus II is found in all non-Australian members of the ochoai species group, i.e. E. brettae , E. obrieni , E. ochoai , E. scariteus , and E. weatherbyi . This plesiomorphy is especially interesting as it links all four Neotropical and the single Nearctic species of the ochoai species group with the Australian representatives E. lambkinae and two unusual species on Australian Scaritinae ( E. divisus and E. olszanowskii ), as well as the two new species, E. ampullaceous sp. nov. and E. tripodus sp. nov. described herein. Nevertheless, E. tripodus is most similar to the Neotropical species E. weatherbyi by having females with well developed seta h. Females of the new species are distinguished from E. weatherbyi by the longer setae h (h 25–41 versus <7 in E. weatherbyi ), males by their elongate genital capsule, and larvae by their exceedingly long setae h2 (h2 ca. 140 versus 3–4 in E. weatherbyi ).

Etymology. The name tripodus (L., tripod-like) refers to the large genital capsule of the male, which is about the same size of legs III, giving this part of the body a tripod-like appearance.

Figures

FIGURE 3. Female Eutarsopolipus. (A) E. ampullaceous sp. nov. venter, showing apodemes and (B) coxal setae; (C) E. tripodus, coxal setae; (D) E. vepreculus, coxal setae; (E) E. walteri, coxal setae. Membranous idiosomal cuticle is shaded grey.

FIGURE 6. Male Eutarsopolipus. (A) E. ampullaceous sp. nov. venter, showing apodemes and (B) coxal setae; (C) E. tripodus, coxal setae; (D) E. vepreculus, coxal setae; (E) E. walteri, coxal setae. Membranous idiosomal cuticle is shaded grey.

FIGURE 9. Larval Eutarsopolipus.(A) E. ampullaceous sp. nov. venter, showing apodemes and (B) coxal setae; (C) E.tripodus, coxal setae; (D) E. vepreculus, coxal setae; (E) E. walteri, coxal setae. Membranous idiosomal cuticle is shaded grey.

FIGURE 11. Eutarsopolipus tripodus sp. nov. Female, dorsum.

FIGURE 12. Eutarsopolipus tripodus sp. nov. Female, legs I–III (A–C).

FIGURE 13. Eutarsopolipus tripodus sp. nov. Male. Genu II with asymmetrical expression of seta l′. Tarsi II–III with minute seta u″ present but obscured.

FIGURE 14. Eutarsopolipus tripodus sp. nov. Larva. Tarsi II–III with minute seta u″ present but not obscured.