Ixodes lanigeri Hornok & Kontschán & Takano & Gotoh & Hassanin & Tu 2024, sp. nov.
Creators: name: Hornok, Sándor
name: Kontschán, Jenő
name: Takano, Ai
name: Gotoh, Yasuhiro
name: Hassanin, Alexandre
name: Tu, Vuong Tan
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Ixodida
Ixodidae
Ixodes
Ixodes lanigeri

description: Ixodes lanigeri Hornok sp. nov.
Figs 2, 3, 4, 5
Diagnosis.
Medium size, light brown prostriate tick with drop shape body of the female. Legs long. Basis capituli dorsally pentagonal, palps short and hypostome medium length. Scutum reverse pentagonal, broadest at mid-length, posteriorly rounded, with long, deep and curved cervical grooves.
Material examined.
Holotype: • female from a female Himalayan whiskered bat (Myotis alticraniatus Osgood), collected in Vietnam (340 m a. s. l., Tho Than Cave, Xuan Son NP, Phu Tho Province: 21.138613 ° N, 104.939903 ° E) by Vuong Tan Tu on December 7, 2020. Paratype # 1: • nymph from a male Chinese water myotis (Myotis laniger Peter), collected in Vietnam (1530 m a. s. l., Ta Phin # 1 Cave, Lao Cai Province: 22.402822 ° N, 103.836787 ° E) by Vuong Tan Tu on December 3, 2020. Paratype # 2: • larva from a male Chinese water myotis (M. laniger), collected in Vietnam (1400 m a. s. l., Co Ma # 1 Cave, Co Ma Commune, Thuan Chau, Son La Province: 21.361139 ° N, 103.507718 ° E) by Vuong Tan Tu on December 17, 2020.
All above specimens are stored in ethanol and deposited at the Department of Parasitology, University of Veterinary Medicine, Budapest, Hungary (holotype and paratype # 1) and the Institute of Ecology and Biological Resources, Hanoi, Vietnam (paratype # 2).
Morphology.
Female (engorged). Length of the idiosoma (from the half point between scapular apices to the middle of posterior margin) 3.38, width 2.74, ratio of idiosomal length / width 1.23 (Fig. 2).
Scutum reverse pentagonal, broadest at half-length, posteriorly rounded (Fig. 3 G).
Length of scutum 1.26, maximum width 1.05, ratio length / width 1.2. On the scutum long, deep and curved cervical grooves, central and marginal rugosities and scattered punctuations visible (Fig. 3 G). Caudolateral edge straight, with slight concavity where cervical grooves terminate. Scutal setae few, more evident laterally (length: 0.035).
Alloscutum with sparse hair covering dorsally. Length of centrodorsal setae 0.13, marginodorsal setae 0.1. Idiosoma with dense hair covering ventrally. Genital aperture flat W-shaped, with posterior concavity along its mid-line, situated slightly posterior to 2 nd intercoxal space. Genital groove diverging backwards, with concavity at the level of 4 th coxae. Spiracular plates asymmetrical, pear-shape, length 0.4, position of opening submarginal, surrounding aeropyles (around a gap of 0.06) in 2–7 rows (Fig. 3 D). Anal valves with setae measuring 0.1. Anal groove slightly converging from mid-length.
Length of gnathosoma (from palpal apices to posterior margin of basis capituli) 0.6, width of basis capituli dorsally 0.5. Ratio of gnathosomal length to basis capituli width 1.2. Length of basis capituli (from base of hypostome to posterior margin of basis capituli) 0.33, ratio of length to width of basis capituli 0.66. Basis capituli shape pentagonal, its sides parallel, anteriorly converging (Fig. 3 A). Caudolateral corner oblique, slightly rounded, without cornuae and continuing as a dark brown lane of sclerotization along the relatively straight posterior margin. Areae porosae very large, elliptical (with their longitudinal axes perpendicular to each other), their breadth 0.18, interval narrow (0.06). Ventrally on basis capituli prominent, caudolaterally projecting auriculae, bearing two longitudinal ridges, posteriorly tapering (Fig. 4 A). Behind auriculae constriction (“ waist ”). Posterior edge of ventral basis medially less, laterally strongly sclerotized and caudolaterally angled (Fig. 4 A), its width shorter than distance between palpal articles I, laterally with a single hair (0.03).
Palps (dorsal view) short, club shape, edge curved medially, relatively straight laterally, length 0.63, maximum width 0.22, ratio length / width 2.9. Palpal hairs few (i. e., 4–6) medially, more numerous (as many as 12–14) laterally, shortest (measuring 0.02) anteriorly, longest (measuring 0.08) posteriorly. Palpal segment I with slight anterior protuberance, ventrally with two setae (0.05) and longitudinal ridge. Palpal segment II 0.33 long, anteriorly broadening, with a strongly sclerotized longitudinal ridge ventrally, both medial and lateral concavity (fovea) near mid-length, and a lateral protuberance near the junction with segment III (Fig. 3 A). Two caudolateral hairs of palpal segment II, in and near the lateral concavity, have medium length (0.05). Palpal segment III 0.26 long, laterally concave, medially convex (Fig. 3 A). Hypostome slightly lanceolate, length 0.27, width 0.1, ratio length / width 2.7. Dental formula 2 / 2 (mid-length), in six rows (but apical part missing) (Fig. 4 A).
Legs long, longer than 5 (Fig. 2). Coxae I asymmetrically trapezoid, coxae II rectangular, all coxae without spines or spurs but caudomedial angle of coxae I strongly sclerotized, with a slight protuberance laterally to it (Fig. 4 A). A single coxal hair posterolaterally long (0.22), anterolaterally shorter (up to 0.1), except on coxae III where these two equal in length. Highest number of hair (N> 5) on coxae IV. Tarsus I. length 1.2, maximum diameter 0.1, length to diameter ratio 12. Haller’s organ open, with six anterior pit sensillae arranged as a group of three, and another three in line.
Nymph (engorged). Length of the idiosoma 2.95 (Fig. 5 A). Scutum broad, reverse pentagonal, broadest close to half-length (Fig. 5 C). Length of scutum 0.61, maximum width 0.56, ratio length / width 1.1. On the scutum straight scapular groove measuring 0.1, and a relatively straight cervical groove reaching caudolateral margin at its middle, with a concavity. The surface has fine reticulate pattern. Punctuations not visible. Lateral scutal seta 0.04 long.
Alloscutum has few 0.08 long hair dorsally. Idiosoma has sparse hair covering ventrally (length: 0.04–0.05 between coxae, 0.1 in mid region and behind). Spiracular plates subcircular in shape, diameter 0.14, within marginal row scattered aeropyles in 1–3 rows, position of opening subcentral. Anal valves with four 0.06–0.07 long setae. Anal grooves nearly parallel.
Length of basis capituli (from base of hypostome to posterior margin of basis capituli) 0.13, width of basis capituli dorsally 0.22, ratio of length to width of basis capituli 0.6 (Fig. 5 B). Basis capituli shape pentagonal, its sides slightly then (anterior to palpal basis) abruptly converging toward the hypostome, dorsally broadest at its caudolateral corners which are perpendicular, lacking cornuae. Posterior margin nearly straight. Three isolated pores observable in place of areae porosae. Ventrally on the basis triangular, sclerotized auriculae, with almost perpendicular lateral and caudal edges (Fig. 5 E).
Palps (dorsal view) short, medial edge curved, lateral edge nearly straight (Fig. 5 C), length 0.23, maximum width 0.095, ratio length / width 2.4. Palpal hairs longest (0.04) laterally on palpal segment II (N = 3) and slightly shorter (0.03) medially (N = 2). Palpal segment II and III 0.12 and 0.1 long, respectively (Fig. 5 B). Palpal segment III narrower than palpal segment II at their junction, forming a laterally concavity. Palpal segment III with dorsal deepening (fovea), and laterally with five short (0.02) and anteriorly with shorter (0.01) hairs. Hypostome missing from paratype # 2.
Legs long and slender. Coxae I trapezoid, their caudomedial corner perpendicular-angled, coxae II rectangular (Fig. 5 D). Coxae II-IV rounded, without spines or spurs. Coxae I and II with long hair (0.11 and 0.09, respectively) medially at mid-length (Fig. 5 D), all coxae with prominent hair of similar length (0.05–0.11) caudolaterally. Tarsus I. length 0.81, maximum diameter 0.09, length to diameter ratio 9.
Larva (engorged). Length of idiosoma 1.12, breadth 0.8, ratio idiosomal length / breadth 1.4 (Fig. 6 A, B).
Scutum reverse pentagonal, posteriorly rounded, broadest at its half-length (Fig. 6 C). Length of scutum 0.34, breadth 0.39, ratio length / breadth 0.87. Surface reticulate, with slight rugosities. Cervical grooves narrow, terminating close to deepest point of the pronounced concavity along curved caudolateral scutal margin (Fig. 6 C). Between carinae and cervical grooves posterolaterally directed, anteriorly convex deepening. In the caudal field of scutum two parallel grooves with length of 0.08 and interval of 0.05 (Fig. 6 C). Scutal setae few (Sc 2: 0.024, Sc 4: 0.036), some further dorsal and ventral setae also missing. Alloscutal setae longest around mid-length; central dorsal setae (Cd 1-2: 0.05) shorter than marginal dorsal setae (Md 1-3: 0.07, Md 5: 0.08, Md 6: 0.07, Md 8: 0.04). Ventrally, sternal setae (St 1: 0.033, St 2: 0.044; St 3: 0.07) mostly shorter than marginal ventral setae (Mv 1: 0.067, Mv 2: 0.086, Mv 3: 0.073).
Gnathosoma: length from base of hypostome to posterior margin of basis 0.094, width of basis capituli dorsally 0.17, ratio of length to width 0.55. Basis capituli dorsally triangular, with straight posterior margin and rounded, oblique caudolateral corner, both showing a dark brown lane (<0.01) of sclerotization. Ventrally on the basis capituli elevated, blunt and triangular auriculae with sclerotized edge (Fig. 6 D). Posterior margin rounded. Palps short, club-shaped, medially curved, laterally slightly convex with prominent dorsal fovea and lateral outward bulging of segment II near the junction with segment III (Fig. 6 C). Dorsally, palpal length 0.15, breadth 0.07, ratio length / breadth 2.2. Segments I-III measure 0.01, 0.08 and 0.06, respectively. Palpal setae longest (0.015) apically and close to junction of II-III segments. Ventrally on palpal segment II porous elevation at the junction with segment III. Hypostome conical, short (0.11), with dental formula 2 / 2.
Legs long. Haller’s organ elongated, longer than maximum breadth (diameter) of tarsus I. Tarsus I length: 0.4, breadth: 0.058. Coxae without spines or spurs. Coxa I trapezoid, with caudomedial corner as elevated, perpendicular angle of dark sclerotization appearing as a short internal spur. Coxae II-III rounded.
Differential diagnosis.
Ixodes lanigeri sp. nov. can be distinguished from I. simplex Neumann and I. fuliginosus Hornok & Takano based on its long legs (tarsus I: length to maximum diameter ratio above 8), and from members of the I. vespertilionis complex (I. vespertilionis, I. collaris, I. nipponrhinolophi) based on its short palps, relevant to all known developmental stages.
Within the I. ariadnae complex, the female of I. lanigeri sp. nov. is different from I. fujitai based on the following characters of the latter: (1) scarce punctuations in the anterior and posterior fields of scutum (Fig. 3 H) (vs denser in I. lanigeri sp. nov.); (2) subcircular spiracular plates (Fig. 3 E) (vs asymmetrical, pear-shape in case of I. lanigeri sp. nov.); (3) gnathosoma approximately 30 % longer than broad (vs only approximately 20 % longer than broad in I. lanigeri sp. nov.); (4) angled, thickened and protruding caudolateral corners of basis capituli (Fig. 3 B) (vs rounded and blunt, oblique in I. lanigeri sp. nov.); (5) subtriangular areae porosae with a broader interval of 0.08 (Fig. 3 B), ratio of width-to-interval 2: 1 (vs broad elliptical areae porosae, with their longitudinal axes perpendicular to each other and a narrower interval of 0.06 in I. lanigeri sp. nov., with a 3: 1 ratio of width-to-interval); (6) lack of sagittal rim anteriorly on palpal article I (Fig. 4 B) (vs observable in I. lanigeri sp. nov.); (7) lack of strongly sclerotized longitudinal ridge ventrally at the basis of palpal article II (Fig. 4 B) (vs present in I. lanigeri sp. nov.), and the two caudolateral hairs of palpal segment II, in and near the lateral concavity, are long (0.1) in I. fujitai (Fig. 4 B) (vs short, 0.05 in I. lanigeri sp. nov.); (8) slightly elevated and sclerotized auricular ridge (Fig. 3 B) (vs prominent auriculae in I. lanigeri sp. nov.); (9) rounded posterior margin of ventral basis (Fig. 4 B) (vs caudolaterally angled posterior margin of I. lanigeri sp. nov.); and (10) rounded coxae, especially coxae II (Fig. 4 B) and IV (vs rectangular coxae II in I. lanigeri sp. nov.).
Differences in comparison with females of I. ariadnae include the following characters. In I. ariadnae the scutum is slightly more elongated (Fig. 3 I) (ratio length / width above 1.25 vs 1.2 in I. lanigeri sp. nov.) and has its maximum width at approximately one-third of its length (vs close to half-length in I. lanigeri sp. nov.). The straight portion is in the middle of the cervical grooves in I. ariadnae (Fig. 3 I), but posteriorly in I. lanigeri sp. nov. The number of pores is low in the caudal region of the scutum of I. ariadnae (Fig. 3 I) vs higher in I. lanigeri sp. nov. The spiracular plates of I. ariadnae are subcircular (Fig. 3 F), with straight portions of its edges (vs asymmetrically pear-shaped in I. lanigeri sp. nov.), diameter smaller (0.33 vs 0.4 in I. lanigeri sp. nov.). Aeropyles occupy up to 10 rows in I. ariadnae (vs up to 7 in I. lanigeri sp. nov.), with narrower margin than the diameter of their opening (vs broad margin in I. lanigeri sp. nov.). Gnathosoma approximately 30 % longer than broad (vs only approximately 20 % longer than broad in I. lanigeri sp. nov.). Dorsally, basis capituli with straight oblique caudolateral corner and wavy edge including that of posterior margin which is strongly concave in middle (Fig. 3 C), vs rounded corner and straight posterior margin in I. lanigeri sp. nov. Shape of areae porosae subtriangular in I. ariadnae (Fig. 3 C) vs elliptical in I. lanigeri sp. nov. Palps of I. ariadnae broader, with length-to-width ratio of 2.4 (Fig. 3 C) (vs 2.9 in I. lanigeri sp. nov.). Ratio of palpal segments II: III 1.6 in I. ariadnae vs 1.27 in I. lanigeri sp. nov. Palpal segment II is laterally concave at its basis in I. ariadnae (Fig. 3 C) (vs close to its mid-length both laterally and medially in I. lanigeri sp. nov.). Surface of palpal segment III convex both laterally and medially in I. ariadnae (Fig. 3 C) (vs laterally concave, medially convex in I. lanigeri sp. nov.). Ventrally on the basis capituli of I. ariadnae “ waist ” (narrowing) and sclerotized posterior edge less evident, unangled and inconspicuous auricular ridges have convex, rounded anterior margin (Fig. 4 C) (vs concave anterior margin surrounding palpal article I. in I. lanigeri sp. nov.). Coxae II-IV of I. ariadnae are symmetrically rounded vs asymmetrically trapezoid or rectangular in I. lanigeri sp. nov.
In comparison with I. collaris nymph: palps slender, elongated, 0.45 (vs short, 0.23 in I. lanigeri sp. nov.) and the scutum is also more elongated (shape index is 1.5 vs 1.1 in I. lanigeri sp. nov.). Within the I. ariadnae complex, the nymph of I. fujitai is unknown. The nymph of I. lanigeri sp. nov. is different from that of I. ariadnae based on the following characters of the latter. The scutum is longer, as indicated by the shape index of 1.2, and broadest at its anterior third (Fig. 7 A) (vs 1.1 in I. lanigeri sp. nov., maximum width close to half-length in I. lanigeri sp. nov.). The ratio of palpal segments II: III 1.7 (Fig. 7 B) (vs 1.2 in I. lanigeri sp. nov.). Ventrally, on the basis of I. ariadnae nymph, less elevated auricular ridges are visible (Fig. 7 D). Spiracular plates oval, with irregular outline in I. ariadnae nymph but subcircular in I. lanigeri sp. nov. Coxae of I. ariadnae nymph are all rounded (Fig. 7 C).
Within the I. ariadnae complex, the larva of I. fujitai is unknown. The larva of I. lanigeri sp. nov. is different from that of I. ariadnae (Fig. 8 A, B) based on the following characters of the latter. Scutum broadest anteriorly to its half-length; its caudolateral edge with only slight concavity (Fig. 8 C) (vs deep in I. lanigeri sp. nov). Cervical grooves not apparent, reaching posterolateral margin of scutum behind its deepest point of concavity. Scutal setae shorter (0.02–0.03) than in I. lanigeri sp. nov. (0.05). Caudal alloscutal setae longer in I. ariadnae larva (0.15 vs 0.04–0.08 in I. lanigeri sp. nov.). Marginal ventral setae longer in I. ariadnae larva (0.12–0.14 vs 0.06–0.09 in I. lanigeri sp. nov.). Palps of I. ariadnae larva laterally straight, with small fovea and dark outline (Fig. 8 C) (vs laterally convex, with prominent fovea in I. lanigeri sp. nov.), but shape index is 2.2 in both species. Palpal setae longer in I. ariadnae (up to 0.05) than in I. lanigeri sp. nov. (0.015). Ventrally, on the basis, capituli auricular ridges of I. ariadnae are less apparent / elevated (Fig. 8 D) than the auriculae in I. lanigeri sp. nov.
GenBank data.
Complete mitochondrial genome sequence from one larva is available in GenBank (LC 797956). Sequences of the amplified parts of the cox 1 and 16 S rRNA genes of I. lanigeri sp. nov. from another larva (collected with paratype # 2), the nymph (paratype # 1) and the female (holotype) are found under the accession numbers PP 079465, PP 503326, PP 503327 and PP 081435, PP 505539, PP 505540 respectively.
Molecular and phylogenetic analyses.
Pairwise comparison of I. lanigeri sp. nov. indicated 5.1 % cox 1 and 2.9 % 16 S rRNA gene sequence differences from I. fujitai, and 11.18 % cox 1 and 5.7 % 16 S rRNA gene sequence difference from I. ariadnae (Table 1). There were up to only 2 bp differences in the amplified part of the cox 1 and 16 S rRNA genes between the larvae, the nymph and female of I. lanigeri sp. nov. The complete mitogenome of I. lanigeri sp. nov. was 95.4 % (13899 / 14570 bp) identical to that of I. fujitai (LC 769934). The phylogenetic relationships of the new tick species from Vietnam are shown in Fig. 9.
Host records and distribution.
Known host species: Myotis alticraniatus, M. laniger. Known geographical range: northern Vietnam.
Etymology.
The name of the new species refers to the host species, the Chinese water myotis (M. laniger) from which the first specimen of the new species was collected.
description: Published as part of Hornok, Sándor, Kontschán, Jenő, Takano, Ai, Gotoh, Yasuhiro, Hassanin, Alexandre & Tu, Vuong Tan, 2024, Description of Ixodes lanigeri sp. nov., a new hard tick species (Acari, Ixodidae) collected from mouse-eared bats (Vespertilionidae, Myotis) in Vietnam, pp. 107-125 in ZooKeys 1215 on pages 107-125, DOI: 10.3897/zookeys.1215.123624