Freyanopterolichus nipponiae Dubinin, 1953

Waki, Tsukasa & Shimano, Satoshi, 2022, Redescription of two parasitic feather mites sampled from the last two Crested Ibises, Nipponia nippon (Temminck, 1835) (Pelecaniformes: Threskiornithidae) lived in Japan, Zootaxa 5116 (1), pp. 136-150 : 144-146

Freyanopterolichus nipponiae Dubinin, 1953

[Japanese name: Toki-enban-umoudani]

( Figs. 7–10 )

Freyanopterolichus nipponiae Dubinin, 1953: 292–294 , fig. 124; Gaud & Atyeo 1996: 93, fig. 314; Waki & Shimano 2020: 1–8, fig.1; Kuroki et al. 2020, fig.2.

Material examined. 4 females and 4 males ( MPM Coll. No. 21821) from feathers of Nipponia nippon (Temminck, 1835) (Threskiornithidae) , Japan, Niigata Prefecture Sado Island, Ministry of the Environment , Sado Japanese Crested Ibis Conservation Center, 21, August 1993 –4, October 1994, feather coll. Dr. Yoshinori Kaneko.

Description. FEMALE ( Figs. 7A–B , 9A–D , 10A–B, E, G ). Dorsal idiosoma. Subcapitulum trapezoidal, length 77–120, width at base 91–139. Body length including gnathosoma 438–490. Idiosoma transversally ovate, slightly wider than long, strongly flattened dorsoventrally, length 386–445 and greatest width 386–445, width including lateral membranes 467–509. Prodorsal shield large, occupying entire surface of prodorsum, roughly triangular, with two pairs of angular lateral incisions, length 79–97, greatest width 228–249, ( Fig. 7A ). Setae vi spiculiform, situated near anterior end of prodorsal shield. Setae si and se situated at posterior margin of this shield, setae si narrowly lanceolate, and setae se long sword-shaped, separated by 104–108. Scapular shields represented by small curved sclerites. Lateral margins of hysterosoma with narrow membranes stretching from sejugal furrow to bases of setae f2; length of hysterosoma 310–330. Hysteronotal shield covering most part of hysterosoma, wider than long, anterior margin straight, length 278–290, greatest width 318–457, most surface with polygonal net-work pattern ( Fig. 10A ), ovate median area near posterior margin with small pit-like lacunae ( Fig. 10B ). Seta c2 narrowly lanceolate, situated on soft tegument near lateral margins of propodosoma. Seta cp long whip-like, situated marginally slightly posterior to bases of setae c2. Setae d2, e2, f2, h2, h3, ps1, ps2 situated near lateral margins of hysterosoma. Setae d2 filiform. Setae e2, f2, ps1 dilated, narrowly lanceolate, macrosetae h2 and h3 dilated along all their length, gradually attenuate to apices. Seta ps2 short filiform. Hysteronotal gland opening gl posteromesal from setae e2. Cupules ip close tosetae f2, cupules im indistinct. Distance between setae and hysteronotal gland openings: si:si 53–64, se:se 104–118, c1:d1 78–89, d1:gl 65–95, d2:gl 93–120, e1:gl 56–68, e1:h1 89–101, h1:h1 114–154, h2:h2 219–247, h3:h3 148–160, ps1:ps1 103–122. Length of dosal setae: vi 11–15, si 78–113, se 156–158, c1 12–23, c2 70–85, cp 126–156, d1 12–19, d2 20–24, e1 16 –24, e2 53 –80, f2 57–82, h1 17–24, h2 266–353, h3 241–357, ps1 63–84. Ventral idiosoma. Epimerite I free. Seta c3 filiform, situated posterior to humeral shields. Epigynum almost semicircular, situated between tips of epimerites I. Oviporus long, shaped as an inverted Y, apodemes of oviporus extending to level of trochanters III ( Figs. 7A , 10E ). Anus close to posterior margin of idiosoma. Length of ventral setae: 1a 35–50, 3a 14–25, 4a 40–52, 4b 38, c3 20–23, ps2 33–49, ps3 17–22, g 20–29. Distance between setae: 1a:4b 64–78, 3a:4b 46–68, 4b:g 18–24, 4a:g 55–68, 4a:ps3 149–169. Legs ( Figs. 9A–D , 10G , Table 1 ). Length of tarsi I–IV: 47–53, 60–63, 58–66 and 61–87, respectively. Length of tarsus I and II ca. 2 times of each greatest width. Setation of legs I–IV (excluding proral setae p and q): tarsi 8–8–4–6; tibiae 1–1–1–1; genua I–IV 2–2–0–0; femora I–IV 1–1–0–0; trochanters I–IV 0–1–1–0; coxae I–IV 1–0–1–0. Solenidiotaxy of legs I–II–III–IV: tarsi 2–1–0–0, tibiae 1–1–1–1, genua 1–1–1–0. Ambulacral discs I with smooth margin, discs of leg II–IV with ca. 10 denticles on distal edges.

MALE. Dorsal idiosoma ( Figs. 8A–B , 9E , 10C–D ). Gnathosoma as in male, length 71–81, width 86–101. Body length including gnathosoma 425–450. Idiosoma transversally ovate, slightly wider than long, length 340–394 and greatest width 423–443, width including lateral membranes 437–448. Length of hysterosoma 281–297. Prodorsal shield as in female, length 75–92 and width 213–228. Setae vi spiculiform, situated near anterior end of prodorsal shield. Setae si narrowly lanceolate, and setae se long sword-shaped, separated by 94–105. Scapular shields represented by small bow-shaped sclerites. Lateral margins of hysterosoma with narrow membranes stretching from sejugal furrow to bases of setae f2. Hysteronotal shield: roughly ovate, wider than long, anterior margin slightly convex, length 245–273 and greatest width 388–401, most surface with numerous polygonal network pattern, area near posterior end additionally with small pits ( Figs. 10C, D ). Setae cp and c3 as in female. Setae d2, e2, f2, h2, h3, ps1, ps2 situated near lateral margins of hysterosoma. Setae d2 filiform. Setae e2, f2, ps2 and ps1 dilated, daggershaped; macrosetae h2 and h3 long dilated along all their length, gradually attenuate to apices. Distance between setae and hysteronotal gland openings: si:si 37–46, se:se 94–105, c1:d1 77–90, d1:gl 74–96, d2:gl 99–108, e1:gl 54–67, e1:h1 80–88, h1:h1 125–131, h2:h2 209–244, h3:h3 140–171, ps1:ps1 81–120. Length of dorsal setae: vi 13–18, si 95–107, se 148–165, c1 18–23, c2 69–91, d1 12–18, d2 22–30, e1 12 –15, e2 77–87, f2 61–74, h1 14–17, h2 186–342, h3 223–294, ps1 67–82. Ventral idiosoma. Epimerites I free, closer to each other than in female. Genital apparatus at level of trochanters IV. Aedeagus hook-shaped ( Fig. 10F ), 43–46 long. Both pairs of genital papillae and setae g approximately at midlength of genital arch. Anus close to posterior margin of opisthosoma. Adanal suckers situated at level of anus, disc-shaped, 23–26 in diameter, with radial patterns. Cupules ip close to f2. Length of ventral setae: 1a 57–74, 3a 43–53, 4a 26–40, 4b 28–49, c3 28–43, ps2 65–70, ps3 25–30, g 30–34. Legs ( Fig. 9E , Table 1 ). Shape and setation as in female except tarsus IV. Length of tarsi I–IV 45–66, 45–65, 53–73, 61–81. Setae d and e of tarsus IV small spine-like, situated in distal 1/3 of segment.

Remarks. Among four species of the genus Freyanopterolichus associated with ibises ( Mégnin & Trouessart 1884; Trouessart & Mégnin 1885; Gaud & Mouchet 1959; Gaud 1982b), F. nipponiae is most close to F. chorioptoides ( Mégnin & Trouessart, 1884) from Bostrychia carunculata (Threskiornithidae) in having: in both sexes, the idiosoma almost circular in shape, macrosetae h2 and h3 dilated, and idiosomal setae f2, and ps1 dagger-shaped; and in females, setae ps2 dagger-shaped. Freyanopterolichus nipponiae can be distinguished from the latter in the following combination of characters. In both sexes, the idiosoma is transversely ovate and slightly wider than long, tarsi I, II are approximately 2 times longer than greatest wide, macrosetae h2 and h3 are dilated along all their length and gradually attenuate to apices; in males, the terminal cleft is absent; in females, setae ps1 are as long as the distance between their bases. In both sexes of F. chorioptoides , the idiosoma is approximately as long as wide, tarsi I, II are approximately 3 times longer than their greatest wide, dilatations of macrosetae h2 and h3 are developed only in the basal part and have a noticeable angular extension on the inner margin; in males, the terminal cleft is shaped as a wide and shallow concavity; in females, setae ps1 are nearly two times as long as the distance between their bases.

Figures

FIGURE 7. Freyanopterolichus nipponiae Dubinin, 1953, female. A—ventral view, B—dorsal view.

FIGURE 8. Freyanopterolichus nipponiae Dubinin, 1953, male. A—ventral view, B—dorsal view.

FIGURE 9. Freyanopterolichus nipponiae Dubinin, 1953, legs. A, B—Leg I, II of female, antiaxial face, C, D—III, IV of female, paraxial face, E—tarsus IV of male, paraxial face.

FIGURE 10. Freyanopterolichus nipponiae Dubinin, 1953 (SEM photos). A—female, dorsal view, B—posterior part of female hysteronotal shield, C— posterior part of male hysteronotal shield, D—male, dorsal view, E—oviporus of female, F—aedeagus, oblique view from left, G: right tarsus I, dorsal view.