Ixodes fujitai Hornok & Takano, 2023

Takano, Ai, Yamauchi, Takeo, Takahashi, Mamoru, Shimoda, Hiroshi, Gotoh, Yasuhiro, Mizuno, Junko, Natsume, Michio, Kontschan, Jeno, Kovats, David, Tu, Vuong Tan & Hornok, Sandor, 2023, Description of three new bat-associated species of hard ticks (Acari, Ixodidae) from Japan, ZooKeys 1180, pp. 1-26 : 1

Ixodes fujitai Hornok & Takano sp. nov.

Figs 6 , 7

Diagnosis.

Medium size (engorged female 6.8 mm long) yellowish tick. Legs long, palps short, areae porosae large. Scutum anteriorly trapezoid, posterolateral edge straight then rounded convex with wrinkled surface along its margin. Hair covering is sparse both dorsally and ventrally.

Material examined.

Holotype: female, from unknown host species, Japan, Shiga, Inukami-gun , 35.222448°N, 136.291747°E (DD), 9 December 1990, H. Fujita coll. Paratypes: two females. (1): from Murina hilgendorfi Peters, Japan, Okayama, Eniwa city, 34.961817°N, 133.631483°E (DD), 3 September 2013, K. Funakoshi coll. (2) : female, from Murina hilgendorfi , Japan, Shiga, Inukami-gun , 35.222448°N, 136.291747°E (DD), 22 April 2016, K. Okumura coll.

Morphology of female (holotype, engorged).

Length of the idiosoma (from the half point between scapular apices to the middle of posterior margin) 6.8, width 4.8, ratio of idiosomal length/width 1.42.

Scutum broad pentagonal (broadest slightly anterior to mid-length), anterior part trapezoid, posterolateral edge straight then rounded convex with wrinkled surface along its margin (Fig. 6C ). Length of scutum 1.2, maximum width 1.03, ratio of length/width 1.17. Posterolateral, converging margin of scutum straight in ~ one 1/4 of scutal length. On the scutum curved, deep cervical grooves reaching posterolateral margin in its anterior part, i.e., at the end of straight edge (behind maximum width), with slight concavity (Fig. 6C - 1 ). Punctuations moderately sparse, large. Dorsal scutal setae few in middle (length 0.015).

Alloscutum with sparse hair covering dorsally. Length of centrodorsal setae 0.125, idiosoma has sparse hair covering ventrally. Genital aperture between 2nd and 3rd intercoxal spaces, as broad horizontal C-shape. Genital groove posteriorly diverging, with narrowing at level of 4th coxae. Spiracular plates subcircular, diameter 0.38, opening elongate (0.06), close to margin (Fig. 6D ). Aeropyles in (2-3):(8-9) rows (minimum: maximum), densely packed, with margin broader than diameter of opening. Anal valves with two long (0.13) posterior setae. Anal groove slightly converging behind anus.

Length of gnathosoma (from palpal apices to posterior margin of basis capituli) 0.66, width of basis capituli dorsally 0.48. Ratio of gnathosomal length to basis capituli width 1.38. Basis capituli pentagonal (Fig. 6A ), its sides anteriorly slightly then sharply converging. At the hypostomal basis dorsal flattening (plateau) (Fig. 6A - 1 ), anteriorly gradually tapering to hypostomal base. Posterior margin wavy, slightly concave in middle, without cornuae but with squared, thickened corners (Fig. 6A - 2 ). Areae porosae large, posterolaterally tapering, their interval 0.08. Ventrally basis capituli converging along straight, dark auricular ridges (Fig. 6B - 1 ) to narrowing ( “waist”), posteriorly diverging (Fig. 6B , dashed line).

Palps (dorsal view) short, club-shaped, broadest anterior to junction of segments II and III as a protuberance medially (Fig. 6A - 3 ), anteriorly rounded. Edge as a broken line medially (both palpal segments II and III with relatively straight medial edge) (Fig. 6A - 4 , - 5 ), straight laterally. Length 0.52, maximum width 0.19, ratio of length/width 2.7. Palpal hairs number 16-18 laterally (length 0.05-0.1), anteriorly five or six short (up to 0.05), medially few (0.02-0.05). Palpal segment II 0.29 long, palpal segment III 0.19 long, their ratio 1.5.

Hypostome broken on holotype (absent on paratype). Dental formula 2/2 where visible.

Legs long and slender. Coxa I subtriangular, coxae II and III trapezoidal with rounded medial edge (coxa II straight in mid-length), coxa IV semicircular. On coxae III and IV caudolateral long hair measuring 0.20-0.22. Tarsus I length 1.5, maximum diameter 0.17, length/diameter ratio 8.8. Hairs on tarsus I dorsally, laterally, and ventrally 0.07-0.30. Haller’s organ elongated, with grouped (non-linear) three anterior pit sensillae, one longer and stout (0.05).

Differential diagnosis.

Ixodes fujitai Hornok & Takano, sp. nov. can be easily distinguished from I. simplex based on its long legs (length to maximum diameter ratio above 8), and from members of the I. vespertilionis complex based on its short palps. Differences in comparison with females of the most similar species, Ixodes ariadnae include the following characters of the latter. In I. ariadnae the scutum is slightly more elongated (ratio of length/width above 1.25 vs below 1.2 in I. fujitai Hornok & Takano, sp. nov.) (Fig. 7C ). Posterolateral, converging margin of scutum in I. ariadnae straight in more than one third of scutal length (i.e., this part is longer than in I. fujitai Hornok & Takano, sp. nov.). On the scutum of I. ariadnae deep cervical grooves are straight in most of their length, reaching posterolateral margin in its middle, with more pronounced concavity (Fig. 7C - 1 ). Punctuations on scutum very sparse. Spiracular plates of I. ariadnae subcircular but with straight portions of its edges (Fig. 7D ), diameter smaller (0.33 vs 0.38 in I. fujitai Hornok & Takano, sp. nov.). Aeropyles loosely packed, with narrower margin than the diameter of their opening. Hypostome has laterally thickened basis (where sides are parallel with longitudinal axis) (Fig. 7A - 1 ). Caudolateral corner of dorsal basis blunt, oblique (Fig. 7A - 2 ) (vs squared, thickened angle in I. fujitai Hornok & Takano, sp. nov.). Posterior margin of basis wavy, strongly concave in middle (vs slightly in I. fujitai Hornok & Takano, sp. nov.). Ventrally basis capituli converging to narrow “waist” posterior to which it is nearly parallel (Fig. 7B dashed line); auricular ridge barely visible, scarcely sclerotised. In I. ariadnae , at the junction of palpal segments II and III no protuberance medially; their medial edge curved (Fig. 7A - 3 , - 4 ) (vs straighter in I. fujitai Hornok & Takano, sp. nov.).

Gene sequences.

Complete mitochondrial genome sequence was deposited in the GenBank (LC769934). All accession numbers relevant to the new species are listed in Suppl. material 1.

Host record.

Known host species: Murina hilgendorfi .

Etymology.

The name of the new species refers to the collector of holotype, the late Dr. Hiromi Fujita (Ohara General Hospital), who was a leading researcher and major author on the topic of ticks and tick-borne pathogens.

Figures

Figure 1. Map of Japan showing the origin of type specimens examined in this study. The blue spots indicate Ixodes nipponrhinolophi Hornok & Takano, sp. nov., the green-coloured spots mark locations of Ixodes fuliginosus Hornok & Takano, sp. nov., and red shows Ixodes fujitai Hornok & Takano, sp. nov. Larger shaded spots indicate the region of origin if the precise location was not known.

Figure 2. The morphology of Ixodes nipponrhinolophi Hornok & Takano, sp. nov.: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D idiosoma ventrally. Numbers are referred to in the text where relevant structures are described. Scale bars: 100 μm.

Figure 3. The morphology of Ixodes collaris: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D idiosoma ventrally. Numbers are referred to in the text where relevant structures are described. Scale bars: 100 μm.

Figure 4. The morphology of Ixodes fuliginosus Hornok & Takano, sp. nov.: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D coxa IV. Numbers are referred to in the text where relevant structures are described. Dashed line indicates the edge of basis capituli. Scale bars: 100 μm.

Figure 5. The morphology of Ixodes simplex: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D coxae III and IV. Numbers are referred to in the text where relevant structures are described. Dashed line indicates the edge of basis capituli. Scale bars: 100 μm.

Figure 6. The morphology of Ixodes fujitai Hornok & Takano, sp. nov.: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D spiracular plate. Numbers are referred to in the text where relevant structures are described. Dashed lines indicate in B the posterolateral edge of ventral basis capituli and in C the maximum scutal width. Scale bars: 100 μm.

Figure 7. The morphology of Ixodes ariadnae: A dorsal aspect of basis capituli B ventral aspect of basis capituli C scutum D spiracular plate. Numbers are referred to in the text where relevant structures are described. Dashed lines indicate in B the posterolateral edge of ventral basis capituli and in C the maximum scutal width. Scale bars: 100 μm.