Ixodes insulae D. Apanaskevich & Barker, 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 : 42-45

Ixodes insulae D. Apanaskevich & Barker n. sp.

Type-host: Morepork— Ninox novaeseelandiae (Gmelin) ( Strigiformes : Strigidae ).

Type-locality: Australia: Tasmania: Derby.

Type-material: Holotype female, from N. novaeseelandiae, Derby (~ 41°8’S, 147°48’E), Tasmania, Australia, 3.viii.1983, R. H. Green; deposited in the USNTC ( USNMENT 01481793 ).

ZooBank registration: The Life Science Identifier (LSID) for Ixodes insulae n. sp. is urn:lsid:zoobank.org:act:D9E68280-2C5E-417B-A2A4-A5A75E5C41F6 .

Etymology: The species name is derived from the Latin insula meaning “island” implying the island of Tasmania where the holotype of this species was collected.

Description. Female [Based on 1 specimen; Fig. 25 .] Idiosoma of moderately engorged specimen broadly suboval. Scutum ( Fig. 25A ) length 1.30 (n = 1), width 0.96 (n = 1), ratio 1.35 (n = 1); lateral margins diverging for approximately 1/2 of scutal length, then converging to broadly rounded posterior margin; lateral carinae absent; cervical grooves shallow reaching posterior quarter of scutal length; relatively sparse very fine punctations evenly distributed throughout scutum; setae ( Fig. 25A ) relatively sparse, very short (c. 0.04 in anterolateral margin of scutum). Setae of alloscutum ( Fig. 25B, C ) numerous, evenly distributed, short in center of alloscutum: c. 0.04 and long in area medial to marginal grooves: c.0.08, setae in area medial to marginal grooves 2.00 times longer than setae in center of alloscutum, ratio scutal length to length of setae in area medial to marginal grooves 17.20 (n = 1). Genital aperture medial to posterior margin of coxae III; genital groove well developed; anal groove oval with open posterior margin; ventral setae numerous, length of preanal setae c. 0.06, evenly distributed. Spiracular plates ( Fig. 25D ) length 0.34 (n = 1), width 0.32 (n = 1), ratio 1.05 (n = 1); broadly suboval.

Gnathosoma ( Fig. 25E, F ) length from palpal apices to cornual apices dorsally 0.76 (n = 1), width of basis capituli dorsally 0.57 (n = 1), ratio 1.34 (n = 1). Dorsal basis capituli ( Fig. 25E ) length from medial insertion of palpal segment I to cornual apices 0.29 (n = 1), ratio width to length 1.98 (n = 1), subrectangular, lateral margins slightly convex, without lateral projections, posterior margin very slightly convex; cornua moderately long, length 0.06 (n = 1), ratio total length of basis capituli, including cornua, to cornual length 4.60 (n = 1), triangular with broadly rounded apex; transversally suboval porose areas large, width 0.19 (n = 1), ratio width of basis capituli dorsally to width of porose area 3.03 (n = 1), clearly distinct, slightly indented, separated by distance of nearly 1/2 of their own width, openings discrete. Ventral basis capituli ( Fig. 25F ) pentagonal; auriculae long, length 0.09 (n = 1), ratio length of gnathosoma dorsally to length of auriculae 8.97 (n = 1), narrow, nearly twice as long as wide, directed posteriorly, with narrowly rounded apex. Lateral surface of basis capituli concave. Palpi ( Fig. 25E–G ) moderately long, length dorsally (segments II and III) 0.36 (n = 1), maximum width (in dorsolateral plane) 0.14 (n = 1), ratio 2.64 (n = 1), length of medial margin of palpal segment I ventrally 0.12 (n = 1); 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 0.10 (n = 1), ratio combined length of palpal segments II and III to length of internal projection on palpal segment I ventrally 3.55 (n = 1); dorsally segment I with short mesodorsal spur at base and small tapering dorsoapical denticle; 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. 25F ) length 0.42 (n = 1), width 0.15 (n = 1), ratio 2.72 (n = 1); 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 short.

Legs moderately long, slender. Coxae ( Fig. 25H ): coxae I-III with internal and external spurs, coxa IV with external spur only; external spur on coxae I-III moderately long, subequal in length, narrow, moderately broadly rounded at apex, directed slightly posteromedially; external spur on coxa IV same as on other coxae but slightly shorter; 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, directed posteriorly; external spur on coxa I at least twice as long as internal spur; no syncoxae. Distally trochanters I-IV ( Fig. 25H ) with long, ventral spur with narrowly rounded apex. Tarsus I length 0.76 (n = 1); tarsus IV length 0.70 (n = 1).

Remarks. Possibly this species was described based on a female and two nymphs from Tasmania by Roberts (1964, 1970) as I. auritulus . Unfortunately, this material was not available for our examination to confirm or deny this possibility. If the identity of the Tasmanian female of I. auritulus of Roberts is confirmed to be I. insulae n. sp., then the nymph should be considered as formally described, although it should be redescribed in greater detail and provided with illustrations.

By having a distinct, anteriorly directed internal projection on palpal segment I, the female of I. insulae n. sp. most closely resembles the following Ixodes (Multidentatus) spp.: I. auritulus , I. brevisetosus n. sp., I. contrarius n. sp., I. cornuae , I. guglielmonei 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. insulae n. sp. can be distinguished from the female of I. cornuae by having short cornua (vs very long cornua in that species); from the female of I. kerguelenensis by having slightly convex posterior margin of basis capituli dorsally (vs sinuously concave margin in that species), longer and posteriorly directed auriculae (vs shorter, slightly posterolaterally directed auriculae in that species), smaller mesodorsal spur and dorsoapical denticle on palpal segment I (vs larger spur and denticle in that species); from the female of I. paranaensis by having longer auriculae (vs very short auriculae in that species); and from the female of I. percavatus by having smaller mesodorsal spur and dorsoapical denticle on palpal segment I (vs larger spur and denticle in that species) and longer internal and external spurs on coxae I-IV (vs shorter spurs in that species) (see Arthur 1960; Wilson 1970; BarrosBattesti et al. 2003).

The female of I. insulae n. sp. can be distinguished from females of other species by the narrow scutum: mean ratio length to width 1.35 (vs broader scutum: mean ratio 1.19 in I. auritulus , 1.25 in I. guglielmonei n. sp. and I. moralesi n. sp., 1.16 in I. robbinsi n. sp. and 1.11 in I. tinamou n. sp.); moderately long setae in center of alloscutum and long setae in 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 2.00 (vs shorter setae in center of alloscutum: mean ratio 3.40 in I. auritulus , 3.75 in I. contrarius n. sp., 3.68 in I. moralesi n. sp., 4.00 in I. rio n. sp. and 2.73 in I. tinamou n. sp.; shorter setae in alloscutal area medial to marginal grooves: mean ratio 1.58 in I. brevisetosus n. sp.; longer setae in center of alloscutum: mean ratio 1.09 in I. guglielmonei n. sp. and 1.14 in I. zealandicus ); long setae of alloscutum medial to marginal grooves: mean ratio length of scutum to length of alloscutal setae medial to marginal grooves 17.20 (vs shorter setae of alloscutum medial to marginal grooves: mean ratio 45.62 in I. brevisetosus n. sp., 20.89 in I. moralesi n. sp. and 26.93 in I. robbinsi n. sp.); narrow gnathosoma: ratio length of gnathosoma to width of basis capituli 1.34 (vs broader gnathosoma: mean ratio 1.25 in I. auritulus , 1.25 in I. contrarius n. sp., 1.28 in I. moralesi n. sp., 1.21 in I. rio n. sp., 1.22 in I. robbinsi n. sp. and 1.24 in I. tinamou n. sp.); basis capituli slightly convex dorsolaterally (vs basis capituli with angular dorsolateral projections in I. brevisetosus n. sp. and I. rio n. sp.); lateral surface of basis capituli concave (vs lateral surface flat in I. brevisetosus n. sp.); posterior margin of basis capituli slightly convex (vs sinuously concave in I. guglielmonei n. sp. and straight to very slightly concave in I. zealandicus ); long cornua: mean ratio length of basis capituli to cornual length 4.60 (vs shorter cornua: mean ratio 14.00 in I. contrarius n. sp., 10.00 in I. rio n. sp., 9.92 in I. tinamou n. sp. and 7.25 in I. zealandicus ); broad porose areas: ratio width of basis capituli to width of porose area 3.03 (vs narrower porose areas: mean ratio 3.61 in I. brevisetosus n. sp. and 3.47 in I. rio n. sp.); auriculae long: mean ratio length of gnathosoma dorsally to length of auriculae 8.97, narrow, directed posteriorly, with narrowly 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 broadly 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 ); 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 3.55 (vs longer projection: mean ratio 2.93 in I. auritulus , 2.77 in I. brevisetosus n. sp., 1.88 in I. contrarius n. sp., 3.08 in I. moralesi n. sp., 2.83 in I. rio n. sp. and 3.02 in I. robbinsi n. sp.; shorter projection: mean ratio 4.94 in I. guglielmonei n. sp. and 4.50 in I. zealandicus ); short mesodorsal spur at base of palpal segment I dorsally (vs spur indistinct in I. auritulus , I. brevisetosus n. sp., I. contrarius n. sp., I. guglielmonei n. sp., I. rio n. sp., I. robbinsi n. sp. and I. tinamou n. sp.); 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.); moderately narrow palpal segments II and III: mean ratio length to width 2.64 (vs narrower segments: mean ratio 2.82 in I. brevisetosus n. sp.; broader segments: mean ratio 2.53 in I. contrarius n. sp., 2.16 in I. guglielmonei 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. auritulus , I. brevisetosus n. sp., I. contrarius n. sp., I. rio n. sp. and I. zealandicus ; noticeably larger species: I. guglielmonei n. sp. See descriptions for measurements).

Collection data for I. insulae n. sp. are listed in the material above. The only collection of this species was made in Australia (Tasmania) ( Fig. 10B ). The single female of I. insulae n. sp. was collected from the morepork, N. novaeseelandiae ( Strigiformes : Strigidae ) during August.

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 25. Ixodes insulae n. sp., female (Derby, Tasmania, Australia, USNMENT 01481793, holotype). A, Scutum; B, Alloscutal setae in central area of alloscutum; C, Alloscutal setae in area of alloscutum medial to marginal grooves; D, Spiracular plate (arrows show orientation of spiracular plate: a, anterior; d, dorsal); E, Gnathosoma, dorsal view; F, Gnathosoma, ventral view; G, Palpal segment I, lateral view (arrows show orientation of palpal segment: a, anterior; d, dorsal); H, Coxae and trochanters. Scale-bars: A, 1 mm; B, C, 0.05 mm; D, 0.2 mm; E, F, H, 0.5 mm; G, 0.1 mm. D.A. Apanaskevich del.