Ixodes brevisetosus D. Apanaskevich, 2022

Apanaskevich, Dmitry A., Apanaskevich, Maria A., Klimov, Pavel B., Edgy, Brett M., Bermúdez, Sergio E., Labruna, Marcelo B., Korzeev, Andrei I. & Barker, Stephen C., 2022, Description of eight new species of Ixodes Latreille, 1795 (Acari: Ixodidae) and redescription of I. auritulus Neumann, 1904, parasites of birds in the Australasian, Nearctic and Neotropical Regions, Zootaxa 5173 (1), pp. 1-73 : 19-28

Ixodes brevisetosus D. Apanaskevich n. sp.

Type-host: Crested berrypecker— Paramythia montium De Vis ( Passeriformes : Melanocharitidae ).

Other hosts: Lesser melampitta— Melampitta lugubris Schlegel ( Passeriformes : Orthonychidae ), mountain mousewarbler— Origma robusta (De Vis) ( Passeriformes : Acanthizidae ), white-winged robin— Peneothello sigillata (De Vis) ( Passeriformes : Petroicidae ), eastern New Guinea mountain rat— Rattus niobe (Thomas) ( Rodentia : Muridae ).

Type-locality: Papua New Guinea: West Sepik: 17 miles northwest of Telefomin, Lake Louise.

Other localities: Papua New Guinea: Morobe: Bulldog Road, 12 miles east of Edie Creek Road, 12 miles south of Edie Creek Road; southwest of Garaina, Moimo.

Type-material: Holotype female, from P. montium, Lake Louise (~ 4°59’S, 141°19’E), 17 miles northwest of Telefomin , West Sepik, Papua New Guinea, 2,800 m alt., 22.iv.1971, A. B. Mirza ( ABM); deposited in the USNTC ( USNMENT 01481775 ) . Paratypes: Papua New Guinea: Morobe: Bulldog Road, 12 miles east of Edie Creek Road (~ 7°20’S, 146°40’E), 2,500 m alt.: 2 females, 1 nymph and 1 larva, from M. lugubris , 11.i.1972, ABM, USNMENT 01481776 . All paratypes are deposited in the USNTC .

Other material: Papua New Guinea: Morobe: Bulldog Road, 12 miles east of Edie Creek Road , 2,500 m alt.: 1 nymph and 10 larvae, from M. lugubris , 6.i.1972, ABM, USNMENT 01481766 ; same locality and altitude: 3 nymphs and 2 larvae, from M. lugubris , 8.i.1972, ABM, USNMENT 01481759 ; same locality and altitude: 2 nymphs and 3 larvae, from M. lugubris , 8.i.1972, ABM, USNMENT 01481758 ; same locality and altitude: 1 nymph and 5 larvae, from M. lugubris , 9.i.1972, ABM, USNMENT 01481760 ; same locality and altitude: 2 nymphs and 6 larvae, from M. lugubris , 9.i.1972, ABM, USNMENT 01481765 ; same locality and altitude: 1 larva, from M. lugubris , 11.i.1972, ABM, USNMENT 01481768 ; same locality and altitude: 2 larvae, from O. robusta , 11.i.1972, ABM, USNMENT 01481757 ; same locality and altitude: 1 nymph, from M. lugubris , 13.vii.1972, ABM, USNMENT 01481774 ; same locality and altitude: 2 larvae, from M. lugubris , 13.vii.1972, ABM, USNMENT 01481767 ; same locality and altitude: 1 nymph, from M. lugubris , 14.vii.1972, ABM, USNMENT 01481771 ; same locality and altitude: 10 nymphs and 8 larvae, from M. lugubris , 16.vii.1972, ABM, USNMENT 01481763 ; same locality and altitude: 2 nymphs and 1 larva, from M. lugubris , 17.vii.1972, ABM, USNMENT 01481772 ; Bulldog Road, 12 miles south of Edie Creek Road , 2,500 m alt.: 2 nymphs, from P. sigillata , 21.vii.1972, ABM, USNMENT 01481762 ; same locality, 2,800 m alt.: 1 nymph, from M. lugubris , 12.viii.1972, ABM, USNMENT 01481770 ; southwest of Garaina, Moimo (~ 7°58’S, 147°3’E), 1,829 m alt.: 1 nymph, from R. niobe , 14.xii.1969, ABM, USNMENT 01481773 ; West Sepik: 17 miles northwest of Telefomin, Lake Louise , 2,800 m alt.: 1 nymph, from P. sigillata , 27.iv.1971, ABM, USNMENT 01481764 ; Unknown province and locality: 1 larva, USNMENT 01481761 ; Unknown province and locality: 1 larva, USNMENT 01481769 . All specimens are deposited in the USNTC .

ZooBank registration: The Life Science Identifier (LSID) for Ixodes brevisetosus n. sp. is urn:lsid:zoobank.org:act:51FC2DFE-E33D-4623-8AC5-2DCFED6B3BB5 .

Etymology: The specific name is derived from the Latin brevis meaning ‘short’ and setosus meaning ‘bristly’ which refers to the short idiosomal setae characteristic of the female, nymph and larva of this species.

Description. Female [Based on 3 specimens; Figs. 11 , 12 .] Idiosoma ( Fig. 11A, F ) length from scapular apices to posterior body margin in nearly unfed specimen 2.28 (n = 1), width in nearly unfed specimen 1.33 (n = 1), ratio 1.71 (n = 1), broadly suboval, widest posterior to mid-length. Scutum ( Fig. 11B, C ) length 1.20–1.22 (1.21; n = 3), width 0.80–0.90 (0.84; n = 3), ratio 1.36–1.50 (1.44; n = 3); lateral margins diverging for approximately 1/2 of scutal length, then converging to broadly rounded posterior margin; lateral carinae absent; cervical grooves very shallow reaching posterior quarter of scutal length; relatively sparse very fine punctations evenly distributed throughout scutum; setae ( Fig. 11B, C ) relatively sparse, very short (c. 0.03 in anterolateral margin of scutum). Alloscutum ( Fig. 11A ) as illustrated; setae ( Fig. 11A, D, E ) numerous, evenly distributed, very short in center of alloscutum: c. 0.02 and in area medial to marginal grooves: c.0.03, setae in area medial to marginal grooves 1.50–1.75 (avg. 1.58) times longer than setae in center of alloscutum; ratio scutal length to length of setae in area medial to marginal grooves 40.82–48.41 (45.62; n = 3). Venter ( Fig. 11F ) as illustrated; genital aperture ( Fig. 11F ) medial to coxae III; genital groove ( Fig. 11F ) well developed; anal groove ( Fig. 11F ) oval with open posterior margin; ventral setae ( Fig. 11F ) numerous, length of preanal setae c. 0.04, evenly distributed. Spiracular plates ( Fig. 12A ) length 0.27–0.28 (0.28; n = 3), width 0.29 (n = 3), ratio 0.94–0.97 (0.96; n = 3); subcircular.

Gnathosoma ( Fig. 12B–D ) length from palpal apices to cornual apices dorsally 0.64–0.68 (0.66; n = 3), width of basis capituli dorsally 0.49–0.50 (0.50; n = 3), ratio 1.31–1.35 (1.33; n = 3). Dorsal basis capituli ( Fig. 12B ) length from medial insertion of palpal segment I to cornual apices 0.24–0.26 (0.25; n = 3), ratio width to length 1.90–2.05 (1.99; n = 3), subhexagonal: with short and angular lateral projections, posterior margin nearly straight or very slightly convex; cornua short, length 0.03–0.05 (0.04; n = 3), ratio total length of basis capituli, including cornua, to cornual length 5.00–7.60 (5.95; n = 3), triangular with broadly rounded apex; transversally suboval porose areas large, width 0.14 (n = 3), ratio width of basis capituli dorsally to width of porose area 3.55–3.64 (3.61; n = 3), clearly distinct, slightly indented, separated by distance of slightly less than 1/2 of their own width, openings discrete. Ventral basis capituli ( Fig. 12C, D ) pentagonal; auriculae long, length 0.07–0.08 (0.07; n = 3), ratio length of gnathosoma dorsally to length of auriculae 8.33–9.93 (8.97; n = 3), narrow, nearly twice as long as wide, directed posteriorly, with moderately broadly rounded apex. Lateral surface of basis capituli flat ( Fig. 12C, D ). Palpi ( Fig. 12B, C ) moderately long, length dorsally (segments II and III) 0.33–0.34 (0.33; n = 3), maximum width (in dorsolateral plane) 0.11–0.12 (0.12; n = 3), ratio 2.74–2.89 (2.82; n = 3), length of medial margin of palpal segment I ventrally 0.16–0.17 (0.16; n = 3); segment I with moderately long internal projection directed anteriorly and giving L-shape to segment I dorsally and ventrally; length of internal projection ventrally from base of palpal segment II to anterior apex 0.11–0.13 (0.12; n = 3), ratio combined length of palpal segments II and III to length of internal projection on palpal segment I ventrally 2.54–3.05 (2.77; n = 3); dorsally segment I with slight transversal ridge at base and moderate tapering dorsoapical denticle, mesodorsal spur indistinct; segments II and III fused with indistinct or barely discernible (mostly medially) suture between them, narrow proximally and gradually widening to broadly rounded apex. Hypostome ( Fig. 12C ) length 0.39–0.42 (0.40; n = 2), width 0.12–0.13 (0.13; n = 2), ratio 3.16–3.29 (3.22; n = 2); base of hypostome nearly at same level as base of palpal segments II, club-shaped, widest close to mid-length; dental formula mostly 4/4, proximal rows 2/2 and then 3/3, distal rows 5/5; denticles sharply pointed; proximal part of hypostome without denticles moderate in length.

Legs moderately long, slender. Coxae ( Fig. 12F, G ): coxae I-III with internal and external spurs, coxa IV with external spur only; external spur on coxae I-IV moderately long, narrow, moderately broadly rounded at apex, directed slightly posteromedially; external spur on coxa I slightly longer than spur on other coxae; external spur on coxae II and III subequal; external spur on coxa IV slightly shorter than on other coxae; internal spur on coxae I-III short, nearly subequal, narrow and narrowly rounded at apex on coxa I, broader and broader rounded at apex on coxae II and III, internal spur on coxa I directed slightly posteromedially, internal spur on coxae II and III directed posteriorly; external spur on coxa I at least twice as long as internal spur; no syncoxae. Distally trochanters I-IV ( Fig. 12F, G ) with moderate ventral spur with narrowly rounded apex. Tarsus I length 0.71–0.75 (0.74; n = 3); tarsus IV length 0.60–0.62 (0.61; n = 3).

Nymph [Based on 29 specimens; Figs. 13 , 14 .] Idiosoma ( Fig. 13C ): broadly suboval, widest posterior to midlength. Scutum ( Fig. 13A ) length 595–689 (632 ± 19; n = 28), width 455–527 (493 ± 18; n = 28), ratio 1.20–1.38 (1.28 ± 0.04; n = 28); lateral margins diverging for approximately half of scutal length, then converging to broadly rounded posterior margin; posterolateral margins nearly straight; lateral carinae lacking; cervical grooves shallow; setae ( Fig. 13A ) relatively sparse, short: length in posterocentral field of scutum 8–10 (9 ± 1; n = 24), shorter than those on alloscutum, distributed as figured. Alloscutum ( Fig. 13B ) as illustrated; setae ( Fig. 13B ) numerous, evenly distributed, short in center of alloscutum: 11–17 (14 ± 2; n = 28) and slightly longer in area medial to marginal grooves: 21–34 (25 ± 2; n = 28), setae in area medial to marginal grooves 1.50–2.40 (1.90 ± 0.23; n = 28) times longer than setae in center of alloscutum; ratio scutal length to length of setae in area medial to marginal grooves 18.75–28.80 (25.08 ± 2.05; n = 28). Anal groove ( Fig. 13C ) oval with open posterior margin; ventral setae ( Fig. 13C ) numerous, evenly distributed. Spiracular plates ( Fig. 13D ) length 136–179 (158 ± 10; n = 27), width 153–179 (168 ± 9; n = 27), ratio 0.88–1.00 (0.94 ± 0.04; n = 27), broadly oval.

Gnathosoma ( Fig. 14A, B ) length from palpal apices to posterior margin of basis capituli ventrally 374–425 (394 ± 12; n = 27), width at dorsal cornua apices 264–298 (282 ± 8; n = 28), ratio 1.34–1.48 (1.40 ± 0.04; n = 27). Basis capituli ( Fig. 14A, B ): dorsally subtriangular, posterior margin slightly convex with long posterolaterally directed cornua; ventrally pentagonal; auriculae long: 38–47 (41 ± 2; n = 27), ratio length of gnathosoma to length of auriculae 8.55–10.89 (9.62 ± 0.61; n = 27), triangular, directed posteriorly. Palpi ( Fig. 14A, B ): elongate, length dorsally (segments II and III) 170–187 (178 ± 6; n = 28), width 68–77 (72 ± 3; n = 28), ratio 2.33–2.63 (2.47 ± 0.09; n = 28); segment I well developed, with relatively long internal projection directed anteriorly and giving L-shape to segment I dorsally and ventrally; length of internal projection ventrally from base of palpal segment II to anterior apex 48–55 (52 ± 2; n = 26), ratio combined length of palpal segments II and III to length of internal projection on palpal segment I ventrally 3.09–3.85 (3.41 ± 0.18; n = 26); segments II and III fused with indistinct suture between them, narrower proximally and gradually widening to broadly rounded apex. Hypostome ( Fig. 14B ) length 180–205 (188 ± 7; n = 24), width 68–80 (72 ± 3; n = 23), ratio 2.40–2.79 (2.63 ± 0.09; n = 23); widest at approximately its mid-length; base of hypostome approximately at same level as base of palpal segment II; proximal portion of hypostome without denticles short, then dental formula 2/2 for approximately 2 or 3 rows, 3/3 for approximately 5–7 rows and 4/4 for approximately 2–4 rows; apex broadly rounded with irregular smaller denticles.

Legs moderately long. Coxae ( Fig. 14C ): coxae I-III with well-developed internal and external spurs, coxa IV with well-developed external spur and indistinct internal spur; external spur on coxae I-IV moderately long, narrow, narrowly to broadly rounded at apex, curved slightly posteromedially; external spur on coxae I-IV nearly subequal; internal spur on coxae I-III moderately long, narrow to broad and narrowly to broadly rounded at apex, slightly shorter than external spur; no syncoxae. Trochanters I-IV ( Fig. 14C ) with short ventral spur. Tarsus I length 417–451 (433 ± 10; n = 27); tarsus IV length 323–349 (332 ± 8; n = 27).

Larva [Based on 42 specimens; Figs. 15 , 16 .] Idiosoma ( Fig. 15B ): broadly suboval, widest close to mid-length. Scutum ( Fig. 16A ) length 305–350 (334 ± 13; n = 12), width 335–375 (359 ± 12; n = 12), ratio 0.88–0.97 (0.93 ± 0.03; n = 12); hexagonal, lateral margins diverging for slightly more than 1/2 of scutal length, then converging to broadly rounded or nearly straight posterior margin; posterolateral margins with very slight depressions; lateral carinae absent; cervical grooves faint, shallow depressions. Setae 5 pairs, length of Sc 2 14–18 (16 ± 1; n = 10); length of Sc 3 13–17 (15 ± 1; n = 12); alloscutum ( Fig. 15A ) as illustrated. Dorsal setae approximately 13–17 pairs (usually 15 or 16); approximately 4–6 (usually 4 or 5) pairs of central dorsals, length of Cd 1 14–21 (17 ± 2; n = 12), length of Cd 2 11–15 (13 ± 1; n = 12); approximately 9–12 (usually 10 or 11) pairs of marginal dorsals combined with supplementaries, length of Md 1 17–23 (20 ± 2; n = 12). Venter ( Fig. 15B ) as illustrated; anal groove indistinct anteriorly and open posteriorly. Ventral setae approximately 12–14 (usually 12 or 13) pairs plus 1 pair on anal valves; 3 pairs of sternals, length of St 1 22–35 (27 ± 3; n = 12); 2 pairs of preanals, length of Pa 1 27–34 (30 ± 3; n = 12), length of Pa 2 33–45 (38 ± 4; n = 12); approximately 4–6 (usually 4 or 5) pairs of premarginals; 3 pairs of marginal ventrals, length of Mv 1 16–20 (19 ± 1; n = 12).

Gnathosoma ( Fig. 16B–D ): length from hypostomal apex to posterior margin of basis capituli ventrally 235– 249 (242 ± 4; n = 12), width at dorsal cornual apices 156–180 (165 ± 7; n = 12); ratio 1.38–1.58 (1.46 ± 0.06; n = 12). Basis capituli ( Fig. 16B–D ): dorsally subtriangular, posterior margin slightly convex with long posterolaterally directed cornua; ventrally pentagonal with moderately long, triangular auriculae, directed posterolaterally. Posthypostomal setae 2 pairs. Palpi ( Fig. 16B, C ): elongate, length (segments II and III) 100–108 (102 ± 2; n = 12), width 40–45 (42 ± 1; n = 12), ratio 2.34–2.50 (2.41 ± 0.05; n = 12); segment I well developed, with moderately long internal projection directed anteriorly and giving L-shape to segment I dorsally and ventrally; length of internal projection ventrally from base of palpal segment II to anterior apex 23–25 (23 ± 1; n = 12), ratio combined length of palpal segments II and III to length of internal projection on palpal segment I ventrally 4.00–4.67 (4.40 ± 0.17; n = 12); segments II and III fused, suture between them indistinct; segment I lacking setae, 10 dorsal and 3 ventral setae on segments II and III combined. Hypostome ( Fig. 16C ): length 108–113 (110 ± 2; n = 12), width 49–58 (52 ± 2; n = 12), ratio 1.95–2.25 (2.12 ± 0.09; n = 12); base of hypostome nearly at same level as articulation of palpal segments I and II; proximal 1/9th portion of hypostomal length without denticles, then dental formula 1/1 for 1 row, 2/2 for 3 to 5 rows and 3/3 for approximately 6 or 7 rows; apex broadly rounded with irregular small denticles.

Legs moderately long. Coxae ( Fig. 16E ): coxa I with internal and external spurs, coxae II and III with external spur only; external spur on coxae I-III moderately long, narrow, narrowly rounded at apex, curved slightly posteromedially; external spur on coxa I slightly longer than spur on other coxae; external spur on coxa III slightly shorter than on coxa II; internal spur on coxae I short, broad and narrowly rounded at apex, shorter than external spur; posteromedian angle of coxa II forming slight, broadly rounded projection; no syncoxae; coxae I–III with 3 setae each. Trochanters I and II with short ventral spur; trochanter III lack of ventral spur ( Fig. 16E ). Tarsus I length 245–265 (260 ± 6; n = 12); tarsus III length 203–243 (227 ± 10; n = 12).

Remarks. By having a distinct, anteriorly directed internal projection on palpal segment I, the female of I. brevisetosus n. sp. most closely resembles the following Ixodes (Multidentatus) spp.: I. auritulus , I. contrarius n. sp., I. cornuae , I. guglielmonei n. sp., I. insulae n. sp., I. kerguelenensis , I. moralesi n. sp., I. paranaensis , I. percavatus , I. rio n. sp., I. robbinsi n. sp., I. tinamou n. sp. and I. zealandicus .

The female of I. brevisetosus n. sp. can be distinguished from the females of I. cornuae by having short cornua (vs very long cornua in that species); from females of I. kerguelenensis and I. percavatus by having the indistinct mesodorsal spur on palpal segment I (vs large, distinct spur in those species); from the female of I. paranaensis by having longer auriculae (vs very short auriculae in that species) (see Arthur 1960; Wilson 1970; Barros-Battesti et al. 2003).

The female of I. brevisetosus n. sp. can be distinguished from females of other species by the narrow scutum: mean ratio length to width 1.44 (vs broader scutum: mean ratio 1.19 in I. auritulus , 1.25 in I. guglielmonei n. sp. and I. moralesi n. sp., 1.35 in I. insulae n. sp., 1.16 in I. robbinsi n. sp. and 1.11 in I. tinamou n. sp.); short setae in both center of alloscutum and alloscutal area medial to marginal grooves: mean ratio length of setae in alloscutal area medial to marginal grooves to length of setae in center of alloscutum 1.58 (vs longer setae in alloscutal area medial to marginal grooves: mean ratio 3.40 in I. auritulus , 3.75 in I. contrarius n. sp., 2.00 in I. insulae n. sp., 3.68 in I. moralesi n. sp., 4.00 in I. rio n. sp., 2.65 in I. robbinsi n. sp. and 2.73 in I. tinamou n. sp.; longer setae in center of alloscutum: mean ratio 1.09 in I. guglielmonei n. sp. and 1.14 in I. zealandicus ); short setae of alloscutum medial to marginal grooves: mean ratio length of scutum to length of alloscutal setae medial to marginal grooves 45.62 (vs longer setae of alloscutum medial to marginal grooves in all other species: mean ratio 12.88 in I. auritulus , 15.03 in I. contrarius n. sp., 15.16 in I. guglielmonei n. sp., 17.20 in I. insulae n. sp., 15.18 in I. rio n. sp., 26.93 in I. robbinsi n. sp., 17.40 in I. tinamou n. sp. and 16.22 in I. zealandicus ); narrow gnathosoma: mean ratio length of gnathosoma to width of basis capituli 1.33 (vs broader gnathosoma: mean ratio 1.25 in I. auritulus , 1.25 in I. contrarius n. sp., 1.21 in I. rio n. sp., 1.22 in I. robbinsi n. sp. and 1.24 in I. tinamou n. sp.); short angular dorsolateral projections of basis capituli (vs all these species, except for I. rio n. sp., have basis capituli without angular dorsolateral projections); lateral surface of basis capituli flat (vs lateral surface concave in all other species); posterior margin of basis capituli slightly convex (vs sinuously concave in I. guglielmonei n. sp. and straight to very slightly concave in I. zealandicus ); moderately long cornua: mean ratio length of basis capituli to cornual length 5.95 (vs shorter cornua: mean ratio 14.00 in I. contrarius n. sp.); narrow porose areas: mean ratio width of basis capituli to width of porose area 3.61 (vs broader porose areas: mean ratio 2.92 in I. auritulus , 2.97 in I. contrarius n. sp., 2.91 in I. guglielmonei n. sp., 3.03 in I. insulae n. sp., 3.19 in I. moralesi n. sp., 2.83 in I. robbinsi n. sp., 3.05 in I. tinamou n. sp. and 2.93 in I. zealandicus ); auriculae long: mean ratio length of gnathosoma dorsally to length of auriculae 8.97, narrow, directed posteriorly, with moderately broadly rounded apex (vs shorter auriculae: mean ratio 28.15 in I. guglielmonei n. sp., 14.59 in I. robbinsi n. sp., 40.07 in I. tinamou n. sp. and 19.54 in I. zealandicus ; auriculae distinctly broader, with broader rounded apex in I. guglielmonei n. sp., I. moralesi n. sp., I. robbinsi n. sp., I. tinamou n. sp. and I. zealandicus ; auriculae directed slightly outwards in I. guglielmonei n. sp., I. tinamou n. sp. and I. zealandicus ); lacking spur at base of palpal segment I dorsally (vs short mesodorsal spur at base of palpal segment I dorsally in I. insulae n. sp., I. moralesi n. sp. and I. zealandicus ); moderately long internal projection on palpal segment I: mean ratio length of palpal segments II and III to length of projection on palpal segment I 2.77 (vs longer projection: mean ratio 1.88 in I. contrarius n. sp.; shorter projection: mean ratio 4.94 in I. guglielmonei n. sp., 3.55 in I. insulae n. sp., 3.57 in I. tinamou n. sp. and 4.50 in I. zealandicus ); moderate dorsoapical spur on palpal segment I (vs indistinct spur in I. contrarius n. sp., I. guglielmonei n. sp., I. rio n. sp., I. robbinsi n. sp. and I. tinamou n. sp.; large, hook-like spur in I. moralesi n. sp.); narrow palpal segments II and III: mean ratio length to width 2.82 (vs broader segments: mean ratio 2.53 in I. contrarius n. sp., 2.16 in I. guglielmonei n. sp., 2.64 in I. insulae n. sp., 2.46 in I. moralesi n. sp., 2.41 in I. robbinsi n. sp., 2.44 in I. tinamou n. sp. and 2.42 in I. zealandicus ); external spur on coxae I-IV relatively long, narrow, sharper at apex (vs shorter, broader spur with broadly rounded apex in I. tinamou n. sp. and I. zealandicus ); generally moderately large species: see description for measurements (vs noticeably smaller species: I. contrarius n. sp. and I. rio n. sp.; noticeably larger species: I. guglielmonei n. sp., I. insulae n. sp., I. moralesi n. sp. and I. robbinsi n. sp.; See descriptions for measurements).

The nymph of I. brevisetosus n. sp. can be distinguished from nymphs of I. auritulus , I. guglielmonei n. sp., I. robbinsi n. sp. and I. tinamou n. sp. by its relatively narrow scutum (vs broader scutum in I. guglielmonei n. sp., I. robbinsi n. sp. and I. tinamou n. sp.), shorter setae in posterocentral field of scutum (vs longer setae in I. guglielmonei n. sp.), short setae on alloscutum in area medial to marginal grooves (vs longer setae in all other species), short setae in center of alloscutum (vs longer setae in I. auritulus , I. guglielmonei n. sp. and I. tinamou n. sp.), setae on alloscutum in area medial to marginal grooves at least 1.5 times longer than setae in center of alloscutum (vs subequal setae in I. guglielmonei n. sp.), relatively large spiracular plate (vs smaller spiracular plate in I. tinamou n. sp.), moderately long and relatively narrow gnathosoma (vs longer and broader gnathosoma in I. guglielmonei n. sp.; shorter gnathosoma in I. tinamou n. sp.), relatively long auriculae (vs shorter auriculae in all other species), relatively short and narrow palpal segments II and III (vs longer and broader segments in I. guglielmonei n. sp.; broader segments in I. robbinsi n. sp. and I. tinamou n. sp.), relatively long internal projection on palpal segment I (vs shorter projection in I. guglielmonei n. sp. and I. tinamou n. sp.), moderately long and broad hypostome (vs narrower hypostome in I. auritulus ; longer and broader hypostome in I. guglielmonei n. sp.; shorter and narrower hypostome in I. tinamou n. sp.), moderately long tarsus I (vs longer tarsus in I. guglielmonei n. sp.) and moderately long tarsus IV (vs longer tarsus in I. guglielmonei n. sp., I. robbinsi n. sp. and I. tinamou n. sp.).

The larva of I. brevisetosus n. sp. can be distinguished from larvae of I. auritulus , I. guglielmonei n. sp. and I. robbinsi n. sp. by the broadly rounded posterior margin of scutum (vs straighter margin in I. guglielmonei n. sp.); poorly distinct sculpture of scutal surface (vs distinctly sculptured surface of scutum in all other species); smaller dimensions of the following characters: length and width of scutum, length of gnathosoma, length and width of palpal segments II and III, length of tarsi I and III (vs larger size of the characters listed in I. guglielmonei n. sp.; broader palpal segments II and III in I. robbinsi n. sp.); shorter setae Sc 2, Sc 3, Md 1, Pm 1 and Mv 1 (vs longer setae in I. auritulus and I. guglielmonei n. sp.); shorter setae Cd 1 and Cd 2 (vs longer setae in all other species); shorter setae St 1 (vs longer setae in I. guglielmonei n. sp.); moderately long setae Pa 1 (vs longer setae in I. guglielmonei n. sp.; shorter setae in I. robbinsi n. sp.); longer setae Pa 2 (vs shorter setae in I. robbinsi n. sp.); longer auriculae (vs shorter auriculae in I. guglielmonei n. sp. and I. robbinsi n. sp.); moderately long anterior projection on palpal segment I (vs longer projection in I. auritulus ; shorter projection in I. guglielmonei n. sp.) and poorly distinct internal spur on coxa II (vs well-developed spur in I. guglielmonei n. sp.).

Collection data for I. brevisetosus n. sp. are listed in the material above. Collections of this species were made in Papua New Guinea (Morobe and West Sepik Provinces) ( Fig. 10B ) at elevations between 1,829 –2,800 meters above sea level.All stages of this species were mostly collected from passeriform birds. Females, nymphs and larvae of this species were collected from the lesser melampitta, M. lugubris ( Passeriformes : Orthonychidae ). A single female was collected from the crested berrypecker, P. montium ( Passeriformes : Melanocharitidae ). Nymphs of I. brevisetosus n. sp. were collected from the white-winged robin, P. sigillata ( Passeriformes : Petroicidae ), while only larvae were taken from the mountain mouse-warbler, O. robusta ( Passeriformes : Acanthizidae ). A single nymph was collected from a mammalian host, namely the eastern New Guinea mountain rat, R. niobe ( Rodentia : Muridae ). Females were collected during January and April, nymphs during January, April, July, August and December, and larvae during January and July.

Figures

FIGURE 10. Map showing the known geographical distribution of Ixodes auritulus Neumann, 1904, I. brevisetosus n. sp., I. contrarius n. sp., I. guglielmonei n. sp., I. insulae n. sp., I. moralesi n. sp., I. rio n. sp., I. robbinsi n. sp. and I. tinamou n. sp. A, Filled star shows the type-locality and filled circles show confirmed localities of I. auritulus; B, Filled asterisk shows the type-locality and filled circles show confirmed localities of I. brevisetosus n. sp., filled star shows the type-locality of I. insulae n. sp.; C, Filled triangle shows the type-locality of I. contrarius n. sp., filled cross shows the type-locality and filled circle shows confirmed locality of I. moralesi n. sp.; D, Filled star shows the type-locality and filled circles show confirmed localities of I. guglielmonei n. sp.; E, Filled star shows the type-locality and filled circle shows confirmed locality of I. rio n. sp., filled asterisk shows the type-locality of I. tinamou n. sp.; F, Filled star shows the type-locality and filled circles show confirmed localities of I. robbinsi n. sp.

FIGURE 11. Ixodes brevisetosus n. sp., scanning electron micrographs of female (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481776, paratype). A, Idiosoma, dorsal view; B, Scutum, dorsal view; C, Scutum, dorsolateral view; D, Alloscutal setae in central area of alloscutum; E, Alloscutal setae in area of alloscutum medial to marginal grooves; F, Idiosoma, ventral view. Scale-bars: A, F, 0.5 mm; B, C, 0.2 mm; D, E, 0.05 mm. SEMs by D.A. Apanaskevich

FIGURE 12. Ixodes brevisetosus n. sp., scanning electron micrographs of female (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481776, paratype).A, Spiracular plate (arrows show orientation of spiracular plate: a, anterior; d, dorsal); B, Gnathosoma, dorsal view; C, Gnathosoma, ventral view; D, Gnathosoma, anteroventral view; E, Palpal segment I, medial view; F, Coxae I–III and trochanters I–III; G, Coxa IV and trochanter IV. Scale-bars: A–E, 0.1 mm; F, G, 0.2 mm. SEMs by D.A. Apanaskevich

FIGURE 13. Ixodes brevisetosus n. sp., scanning electron micrographs of nymph (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481774).A, Scutum; B,Alloscutum; C, Idiosoma, ventral view; D, Spiracular plate (arrows show orientation of spiracular plate: a, anterior; d, dorsal). Scale-bars: 0.1 mm. SEMs by D.A. Apanaskevich

FIGURE 14. Ixodes brevisetosus n. sp., scanning electron micrographs of nymph (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481774). A, Gnathosoma, dorsal view; B, Gnathosoma, ventral view; C, Coxae and trochanters. Scale-bars: 0.1 mm. SEMs by D.A. Apanaskevich

FIGURE 15 Ixodes brevisetosus n. sp., scanning electron micrographs of larva (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481760). A, Alloscutum; B, Idiosoma, ventral view. Scale-bars: 0.1 mm. SEMs by D.A. Apanaskevich

FIGURE 16. Ixodes brevisetosus n. sp., scanning electron micrographs of larva (12 miles east of Edie Creek Road, Bulldog Road, Morobe, Papua New Guinea, USNMENT 01481760). A, Scutum; B, Gnathosoma, dorsal view; C, Gnathosoma, ventral view; D, Gnathosoma, anteroventral view; E, Coxae and trochanters. Scale-bars: A, E, 0.1 mm; B–D, 0.05 mm. SEMs by D.A. Apanaskevich