Odontoscirus nipponicus Shiba, 1985

Wu, You-Fang, Jin, Dao-Chao, Yi, Tian-Ci & Guo, Jian-Jun, 2022, Redescription and new record of Odontoscirus nipponicus Shiba, 1985 (Bdellidae Odontoscirinae) from China with a description of its ontogeny, Zootaxa 5187 (1), pp. 232-248 : 233-247

publication ID	https://doi.org/ 10.11646/zootaxa.5187.1.13
publication LSID	lsid:zoobank.org:pub:1D7A82FC-73F3-4C81-8AAB-521151A68579
DOI	https://doi.org/10.5281/zenodo.14372181
persistent identifier	https://treatment.plazi.org/id/03A68789-FFBF-E316-FF76-FC4465F2511B
treatment provided by	Plazi
scientific name	Odontoscirus nipponicus Shiba, 1985
status

Treatment

Description

Adults, Male (n=2)

( Figures 1–10 View FIGURES 1–4 View FIGURE 5–6 View FIGURES 7–10 )

Body length (including gnathosoma) 1115–1138, idiosoma 793–838, body width 441–452.

Gnathosoma ( Fig. 1–3 View FIGURES 1–4 ). Gnathosoma length 317–338, width 94–101. Subcapitulum with broken longitudinal striae from vh 6 to vh 3, with broken transversely striations from vh 2 to base of subcapitulum, six pairs of vh and one pair of DHS ( Fig. 1 View FIGURES 1–4 ), vh 1 31–33, vh 2 35–42, vh 3 34–37, vh 4 35–40, vh 5 38–39, vh 6 34–37, DHS 48–53. Cheliceral length 305–320, width 74–92, with reticulated striae and inflated basally, fixed digit with one tooth and movable digit with five teeth ( Fig. 2 View FIGURES 1–4 ), with two setae, proximal setae 32–36, distal setae 68–74, distance between proximal and distal setae 41–52. Palp five-segmented ( Fig. 3 View FIGURES 1–4 ), total length 389–440, trochanter 13–14, basifemur 174–200, telofemur 26–32, genu 19–25, tibiotarsus 139–172, VES 172–185, DES 176–195; palp chaetotaxy: trochanter 0, basifemur 6 sts, telofemur 1 sts, genu 4 sts, tibiotarsus 4 sts, 1 bsl, two long terminal setae (VES, DES) ( TABLE 1 View TABLE 1 ).

Dorsum ( Fig. 5 View FIGURE 5–6 ). Prodorsum with broken transverse striae between at and pt; at and pt lost, lps absent, mps nude; two pairs of eyes, diameters of anterior lateral eye 23–29, and posterior lateral eye 22–27, and with oblique striae between anterior and posterior lateral eyes; hysterosomal striae not obvious, setae minutely plumose; hysterosomal region with three cupules ia, im and ip at level of setae d 1, e 1 and f 2. Measurements of dorsal setae as follows: at?, pt?, mps 90–91, c 1 58–63, c 2 61–67, d 1 54–55, e 1 52 –53, f 1 50–51, f 2 44–47, h 1 51–56, h 2 47–49.

Venter ( Fig. 6 View FIGURE 5–6 ). Broken longitudinal striae between coxae I–II and III–IV and transverse between coxae II–III; aggenital region with three pairs of setae; genital valves with seven pairs of setae. Anal region with two pairs of ps; amphioid sclerites with nine pairs of setae ( Fig. 4 View FIGURES 1–4 ).

Legs ( Figs. 7–10 View FIGURES 7–10 ). Measurements of legs as follows: leg I 712–782, leg II 682–698, leg III 740–843, leg IV 884–1019; setal formula of leg segments as follows: coxae I–IV 5-3-4/5-2 sts; trochanters I–IV 1-1-1-1 sts; basifemora I–IV 9(10)-8(9)-6(7)-3 sts; telofemora I–IV 8(7)-8(7)-3(4)-3(4) sts; genua I–IV 6 sts, 3 asl, 2 bsl -5 sts, 3 asl -4 sts, 2 asl -4 sts, 2 asl; tibiae I–IV 8 sts, 2 asl, 2 bsl, 1 pe, 1 T -8 sts, 1 asl, 1 bsl, 1 T -7 sts, 1 bsl -6 sts, 1 T; tarsi I–IV 32 sts, 1 asl, 3 bsl, 1 pe -31 sts, 1 asl, 2 bsl, 1 pe -29 sts, 1 T -21 sts, 1 T ( TABLE 2 View TABLE 2 ).

Female (n=2)

( Figures 11 View FIGURES 11–14 –20)

Body length (including gnathosoma) 1076–1310, idiosoma 740–985, body width 397–515.

Gnathosoma ( Fig. 11–13 View FIGURES 11–14 ). Gnathosoma length 332–333, width 94–105. Subcapitulum striae and setae resembling male ( Fig. 11 View FIGURES 11–14 ), vh 1 31–33, vh 2 31–34, vh 3 36–40, vh 4 33–40, vh 5 35–43, vh 6 35–37, DHS 50–63. Chelicera resembling male; cheliceral length 313–320, width 82–92 ( Fig. 12 View FIGURES 11–14 ), with two setae, proximal setae 40–49, distal setae 74–77, distance between proximal and distal setae 45–54. Palp tibiotarsus missing ( Fig. 13 View FIGURES 11–14 ), palp chaetotaxy: trochanter 0, basifemur 6 sts, telofemur 1 sts, genu 4 sts.

Dorsum ( Fig. 15 View FIGURE 15–16 ). Resembling male, prodorsum with broken transverse striae between at and pt; at and pt lost, lps absent, mps nude; two pairs of eyes (eyes on the left are covered because the specimen is slightly twisted), diameters of anterior lateral eye 25–28, and posterior lateral eye 24–27; hysterosoma with continuous and longitudinal striae between setae c 1, d 1, e 1, f 1, with continuous transverse striae between setae h 1 and h 2. Measurements of dorsal setae as follows: at?, pt?, mps 89–92, c 1 56–60, c 2 60–66, d 1 55–58, e 1 49 –52, f 1 50–52, f 2 47–54, h 1 51–56, h 2 48–51.

Venter ( Fig. 16 View FIGURE 15–16 ). Resembling male, broken longitudinal striae between coxae I–II, continuous longitudinal striae III–IV and transverse between coxae II–III; setae of venter resembling male; ovipositor with 20 setae ( Fig. 14 View FIGURES 11–14 ).

Legs (Figs. 17–20). Measurements of legs as follows: leg I 687–762, leg II 654–675, leg III 813–829, leg IV 844–990; Setal formula of leg segments as follows: coxae I–IV 5-3-3/4-2 sts; trochanters I–IV 1-1-1-1 sts; basifemora I–IV 10-8-6-3 sts; telofemora I–IV 8-7-4-4 sts; genua I–IV 6 sts, 3 asl, 2 bsl -4 sts, 3 asl -4 sts, 2 asl -4 sts, 2 asl; tibiae I–IV 8 sts, 2 asl, 2 bsl, 1 pe, 1 T -8 sts, 1 asl, 1 bsl, 1 T -6 sts, 1 bsl -6 sts, 1 T; tarsi I–IV 28 sts, 1 asl, 3 bsl, 1 pe -29 sts, 1 asl, 2 bsl, 1 pe -27 sts, 1 T -22 sts, 1 T ( TABLE 2 View TABLE 2 ).

Immature stages

Tritonymph (n=4)

( Figures 21–29 View FIGURES 21–23 View FIGURE 24–25 View FIGURES 26–29 )

Body length (including gnathosoma) 1011–1291, idiosoma 695–969, body width 365–595.

Gnathosoma ( Fig. 21–23 View FIGURES 21–23 ). Gnathosoma length 276–321, width 82–84. Subcapitulum striae resembling male ( Fig. 21 View FIGURES 21–23 ), five pairs of vh, vh 1 23–29, vh 2 27–37, vh 3 28–39, vh 4 31–42, vh 5 27–37, DHS 34–45. Cheliceral length 255–291, width 72–84, reticulated striae simpler than adults, fixed digit with one tooth and movable digit with five teeth ( Fig. 22 View FIGURES 21–23 ), with two setae, proximal setae 33–42, distal setae 61–75, distance between proximal and distal setae 30–46. Palp five-segmented ( Fig. 23 View FIGURES 21–23 ), total length 295–378, trochanter 13–14, basifemur 129–170, telofemur 23–36, genu 22–25, tibiotarsus 109–137, VES 128–163, DES 139–175, palp chaetotaxy: trochanter 0, basifemur 6 sts, telofemur 1 sts, genu 4 sts, tibiotarsus 4 sts, 1 bsl, two long terminal setae (VES, DES) ( TABLE 1 View TABLE 1 ).

Dorsum ( Fig. 24 View FIGURE 24–25 ). Resembling female, diameters of anterior lateral eye 18–22, and posterior lateral eye 17–18. Measurements of dorsal setae as follows: at?, pt?, mps 65–76, c 1 46–57, c 2 50–68, d 1 42–56, e 1 42 –54, f 1 46–55, f 2 43–55, h 1 44–52, h 2 41–51.

Venter ( Fig. 25 View FIGURE 24–25 ). Resembling male, striae of venter not clear; aggenital region with three pairs of setae; Genital valves with four pairs of setae; Anal region with two pairs of ps.

Legs ( Figs. 26–29 View FIGURES 26–29 ). Measurements of legs as follows: leg I 571–674, leg II 542–651, leg III 624–638, leg IV 725–860; setal formula of leg segments as follows: coxae I–IV 5-3-4-2 sts; trochanters I–IV 1-1-1-1 sts; basifemora I–IV 9-7(8)-6-3 sts; telofemora I–IV 6(7)-5(6)-4-4 sts; genua I–IV 5(6) sts, 2 asl, 2 bsl -4 sts, 3 asl -4 sts, 2 asl -4 sts, 1 asl; tibiae I–IV 8(9) sts, 1 asl, 2 bsl, 1 pe, 1 T -8(7) sts, 1 asl, 1 bsl, 1 T -7(6) sts, 1 bsl -5(6) sts, 1 T; tarsi I–IV 25 sts, 1 asl, 3 bsl, 1 pe -27 sts, 3 bsl, 1 pe -22 sts, 1 T -22 sts, 1 T ( TABLE 2 View TABLE 2 ).

Deutonymph (n=3)

( Figures 30–38 View FIGURES 30–32 View FIGURE 33–34 View FIGURES 35–38 )

Body length (including gnathosoma) 660–712, idiosoma 465–505, body width 255–288.

Gnathosoma ( Fig. 30–32 View FIGURES 30–32 ). Gnathosoma length 192–230, width 57–62. Subcapitulum striae resembling tritonymph ( Fig. 30 View FIGURES 30–32 ), four pairs of vh, vh 1 16–21, vh 2 21–24, vh 3 27–29, vh 4 28–29, DHS 25–28. Cheliceral length 185–196, width 63–66, striae simpler than tritonymph, fixed digit with one tooth and movable digit with five teeth ( Fig. 31 View FIGURES 30–32 ), with two setae, proximal setae 19–23, distal setae 43–51, distance between proximal and distal setae 31–34. Palp five-segmented ( Fig.32 View FIGURES 30–32 ), total length 204–259, trochanter 10–11, basifemur 75–107, telofemur 15–25, genu 15–20, tibiotarsus 78–98, VES 97–105, DES 100–114, palp chaetotaxy: trochanter 0, basifemur 4 sts, telofemur 1 sts, genu 4 sts, tibiotarsus 4 sts, 1 bsl, two long terminal setae (VES, DES) ( TABLE 1 View TABLE 1 ).

Dorsum ( Fig. 33 View FIGURE 33–34 ). Resembling tritonymph, hysterosoma striae not obvious; diameters of anterior lateral eye 13–14, and posterior lateral eye 10–11. Measurements of dorsal setae as follows: at 89–90, pt?, mps 44–48, c 1 35–44, c 2 40–44, d 1 38–39, e 1 38 –39, f 1 38–41, f 2 37–38, h 1 38–40, h 2 35–37.

Venter ( Fig. 34 View FIGURE 33–34 ). Resembling tritonymph, striae of venter not obvious; aggenital region with two pairs of setae; genital valves with 2-3 pairs of setae (generally there are only two setae on each genital valve, but there is one exanimated specimen with three setae on the left side); anal region with two pairs of ps.

Legs ( Figs. 35–38 View FIGURES 35–38 ). Measurements of legs as follows: leg I 399–445, leg II 328–391, leg III 400–475, leg IV 457–532; setal formula of leg segments as follows: coxae I–IV 4/5-3-4(3)-2 sts; trochanters I–IV 1-1-1-1 sts; basifemora I–IV 5-3-2-1 sts; telofemora I–IV 5-5-4-4 sts; genua I–IV 3(4) sts, 1 asl, 2 bsl -4 sts, 1 asl -4 sts, 1 asl -4 sts, 1 asl; tibiae I–IV 4 sts, 1 asl, 2 bsl, 1 pe, 1 T -4 sts, 1 asl, 1 bsl, 1 T -5(6) sts, 1 bsl -5(4) sts, 1 T; tarsi I–IV 20 sts, 3 bsl, 1 pe -19 sts, 3 bsl, 1 pe -19 sts, 1 T -15 sts, 1 T ( TABLE 2 View TABLE 2 ).

Protonymph (n=3)

( Figures 39–47 View FIGURES 39–41 View FIGURE 42–43 View FIGURES 44–47 )

Body length (including gnathosoma) 515–624, idiosoma 360–460, body width 229–278.

Gnathosoma ( Fig. 39–41 View FIGURES 39–41 ). Gnathosoma length 148–168, width 56–74. Subcapitulum striae resembling deutonymph ( Fig. 39 View FIGURES 39–41 ), three pairs of vh setae, vh 1 18–24, vh 2 17–25, vh 3 20–24, DHS 17–19. Cheliceral length 140–156, width 40–47, striae simpler than deutonymph, fixed digit with one tooth and movable digit with five teeth ( Fig. 40 View FIGURES 39–41 ), with two setae, proximal setae 18–24, distal setae 37–40, distance between proximal and distal setae 21–25. Palp five-segmented ( Fig.41 View FIGURES 39–41 ), total length 160–166, trochanter 8–9, basifemur 62–64, telofemur 15–16, genu 13–15, tibiotarsus 58–62, VES 74–78, DES 80–83, palp chaetotaxy same as deutonymph ( TABLE 1 View TABLE 1 ).

Dorsum ( Fig. 42 View FIGURE 42–43 ). Resembling tritonymph, but the slide deformed, hysterosoma striae not clear; diameters of anterior lateral eye 10–13, and posterior lateral eye deformed. Measurements of dorsal setae as follows: at?, pt?, mps 35–44, c 1 26–38, c 2 33–37, d 1 31–43, e 1 30 –47, f 1 31–46, f 2 33–40, h 1 36–48, h 2 32–42.

Venter ( Fig. 43 View FIGURE 42–43 ). Striae of venter not clear; aggenital region with one pairs of setae; genital valves with one pairs of setae; anal region with two pairs of ps.

Legs ( Figs. 44–47 View FIGURES 44–47 ). Measurements of legs as follows: leg I 395–372, leg II 245–341, leg III 285–378, leg IV 280–376; setal formula of leg segments as follows: coxae I–IV 4-2-3-0 sts; trochanters I–IV 1-1-1-0 sts; basifemora I–IV 4-3-2-0 sts; telofemora I–IV 5-5-4-0 sts; genua I–IV 4 sts, 1 asl, 1 bsl -4 sts, 1 asl -4 sts, 1 asl -0 sts; tibiae I–IV 4 sts, 1 asl, 2 bsl, 1 pe, 1 T -4 sts, 1 asl, 1 bsl, 1 T -5 sts, 1 bsl -0 sts; tarsi I–IV 18 sts, 2 bsl, 1 pe -17 sts, 1 bsl, 1 pe -15 sts, 1 T -7 sts ( TABLE 2 View TABLE 2 ).

Larva (n=3)

( Figures 48–55 View FIGURES 48–50 View FIGURE 51–52 View FIGURES 53–55 )

Body length (including gnathosoma) 482–549, idiosoma 366–416, body width 195–251.

Gnathosoma ( Fig. 48–50 View FIGURES 48–50 ). Gnathosoma length 118–132, width 40–54. Subcapitulum striae resembling protonymph ( Fig. 48 View FIGURES 48–50 ), two pairs of vh, vh 1 16–19, vh 2 16–20, DHS 14–17. Cheliceral length 96–122, width 33–41, striae simpler than protonymph, fixed digit with one tooth and movable digit with five teeth ( Fig. 49 View FIGURES 48–50 ), with two setae, proximal setae 12–14, distal setae 33–37, distance between proximal and distal setae 19–24. Palp five-segmented ( Fig. 50 View FIGURES 48–50 ), total length 118–144, trochanter 7–8, basifemur 46–55, telofemur 13–17, genu 13–14, tibiotarsus 33–43, VES 54–72, DES 57–78, palp chaetotaxy: trochanter 0, basifemur 2 sts, telofemur 1 sts, genu 4 sts, tibiotarsus 4 sts, 1 bsl, two long terminal setae (VES, DES) ( TABLE 1 View TABLE 1 ).

Dorsum ( Fig. 51 View FIGURE 51–52 ). Striae resembling protonymph, hysterosoma striae not clear; only one pair of eyes 8–10. Measurements of dorsal setae as follows: at 58–64, pt?, mps 27–38, c 1 19–38, c 2 26–38, d 1 24–35, e 1 25 –36, f 1 28–44, f

29–40, h

23–43, h

28–41.

Venter ( Fig. 52 View FIGURE 51–52 ). Striae of venter not clear; no genital valves, genital seta, aggenital seta and ps seta.

Legs ( Figs. 53–55 View FIGURES 53–55 ). Three legs; measurements of legs as follows: leg I 188–269, leg II 184–246, leg III 240– 277; setal formula of leg segments as follows: coxae I–III 2-1-2 sts; trochanters I–III 0-0-0 sts; femora I–III 7-7(6)-5 sts; genua I–III 4 sts, 1 asl, 1 bsl -4 sts, 1 asl -4 sts, 1 asl; tibiae I–IV 5(4) sts, 2 bsl, 1 pe -4 sts, 2 bsl, 1 pe -5 sts, 1 bsl; tarsi I–III 16 sts, 2 bsl, 1 pe -14 sts, 2 bsl, 1 pe -13 sts, 1 T ( TABLE 2 View TABLE 2 ).

Remarks

Species identification

These specimens collected from China resemble Odontoscirus nipponicus from Japan ( Shiba 1985). The following characters are found on both of these specimens: (1) the palp tibiotarsus with seven setae; (2) chelicera with reticulated striae and inflated basally and the proximal setae about 1/2 length distal setae; (3) subcapitulum with broken longitudinal striae from vh 6 to vh 3, with broken transversely striations from vh 2 to the base; (4) prodorsum with broken transverse striae between at and pt and hysterosoma setae minutely plumose; (5) aggenital region with three pairs of setae; Genital valves with seven pairs of setae; (6) coxae I–IV 5-3-4-2; trochanters I–IV 1-1-1-1 sts; basifemora I–IV 9(10)-8(9)-6(7)-3.

There only a few small morphological differences in these specimens: (1) The basifemur of palp with six setae from China, but seven from Japan; (2) vh 5 about 4/5 length of dorsal hypostomal setae from China, but equal from Japan; (3) telofemora I–IV 8(7)-8(7)-3(4)-3(4) sts from China, but 7-7-5-4 from Japan.

Although these specimens have a few small differences, we regard them as minor intraspecific variations.

Ontogeny of O. nipponicus

Shiba (1985) described O. nipponicus based on the female but included adult males in the paratypic series and nymphs in the material examined. This material has not been reexamined and the non-female life stages have remained undescribed, and to our knowledge, there was no subsequent record of that species ( Hernandes et al. 2016).

In this paper, we redescribed the female and described the male and the immature stages for the first time. By comparing the morphological characteristic of the female and the male, the adult and immature stages, we show that the male resembles the female in most respects, except for the smaller size, the presence of the amphioid sclerite, and by the absence of ovipositor; the changes of ontogeny mainly focus on the striae of chelicera, numbers of vh, setae on palp basifemur, ag, g, ps and leg chaetotaxy. The trend of chaetotaxy changed is similar to other Bdellidae ( Bdella: van Der Schyff et al. 2005 ; Wu et al. 2020; Bdellodes: Ueckermann et al. 2007 ; Trachymolgus: Fisher et al. 2011 ).

Gnathosoma . Chelicera are almost without striae in the larvae; and with the development of O. nipponicus , the striae become more and more complex. Subcapitulum with two pairs of vh on larvae, each subsequent stage adds one more pair, i.e., 3 pairs in protonymph, 4 in deutonymph, 5 in tritonymph and 6 in adults; setae on palp basifemur with two setae on larvae, four setae on protonymphs and deutonymphs, six setae on tritonymphs and adults ( TABLE 1 View TABLE 1 ).

Genital region. There are no genital plates, g and ag on larvae, and then g and ag increase with the development of life stage. Almost all life stages are with two pairs of ps but larvae without ps. ( TABLE 1 View TABLE 1 )

Leg. There are three pairs of legs on larvae, four pairs of legs in subsequent stages. And the setae of leg increase with the life stage. ( TABLE 2 View TABLE 2 )

Above all will help us understanding ontogeny of O. nipponicus , and provide literature for studying ontogeny of Odontoscirus .

Voucher material

Two males ( HN-OD-2017082723 ; HN-OD-2017082901 ); two females ( HN-OD-2017082902 ; HN-OD-2017082903 ); four tritonymphs ( HN-OD-2017082904 ; HN-OD-2017082801 ; HN-OD-2017082802 ; HN-OD-2017082601 ); three deutonymphs ( HN-OD-2017082905–2017082907 ); three protonymphs ( HN-OD-2017082908–2017082910 ); three larvae (HN-OD-2017082911–2017082913), collected from moss and fallen leaves, Shunhuang Mountain National Nature Reserve (111°0′26.35E, 26°14′8.17N) Xinning County, Hunan Province, P. R. China on August, 2017, by Mao-Yuan Yao and Yan Shen GoogleMaps .