Aponychus firmianae ( Ma & Yuan, 1965 )

Pan, Xiao-Juan, Jin, Dao-Chao & Yi, Tian-Ci, 2023, Redescription of three species of Aponychus from China with ontogenetic development and morphological variations of A. corpuzae (Acariformes: Tetranychidae), Zootaxa 5324 (1), pp. 185-226 : 210-217

Aponychus firmianae ( Ma & Yuan, 1965)

( Figs 27–34 )

Euteranychus firmianae, Ma & Yuan, 1954: 247 (original description).

Aponychus firmianae, Ehara, 1980: 206 (new combination).

Chinotetranychus firmianae, Ma & Yuan, 1982: 109 (new combination, type species of Chinotetranychus ).

Aponychus firmianae, Rimando & Corpuz-Raros, 1996: 12 (new combination).

Material examined

One female and three males, collected on leaves of Firmiana simplex (Malvaceae) , from Shanghai City, China, by En-Pei Ma, on September 27, 1982. Five females, collected on leaves of Firmiana simplex , from Ruijin, Zhejiang Province, China, by En-Pei Ma, in July, 1987. All specimens are deposited at the Institute of Entomology, Guizhou University, China (GUGC).

Redescription

Female (n = 6)

Dorsum ( Figs 27–28 ). Idiosoma roughly round. Length of idiosoma 347–399 excluding gnathosoma, 414–479 including gnathosoma, 286–314 wide. Integument very finely plicate; in prodorsal and pygidial regions, surface plicae forming an irregular network pattern; surface cuticle appears soft and forms irregular folds and ridges with strong pattern on prodorsum ( Fig. 28 ). Prodorsum with 3 pairs of cylindrical lanceolate setae inserted on strong tubercles, covered with short barbs, v 2 41–52, sc 1 64–76 and sc 2 49–61. Distances between setal bases: v 2 – v 2 71–83, sc 1 – sc 1 90–123.

Hysterosoma with 11 pairs of setae (c 1–3, d 1 – 2, e 1–2, f 2, h 1–3), similar in shape to prodorsal setae, except with h 2–3 of differing morphology, similar to other ventral setae and inserted posteroventrally. Dorsal central pairs of setae (c 1, d 1 and e 1) inserted adjacent to each other; setae c 2 inserted adjacent to c 3; setae f 1 and f 2 appear marginally positioned; setae c 1, d 1 and e 1 as long as the distance to the seta in the next setal row. Length of setae: c 1 53–61, c 2 66–77, c 3 44–57, d 1 53–65, d 2 67–77, e 1 50 –58, e 2 57 –71, f 2 26–34, h 1 40–51, h 2 20–30, h 3 30–47. Distances between setal bases: c 1 – c 1 18–25, d 1 – d 1 34–46, e 1 – e 1 23 –37, f 1 – f 1 97–119, h 1 – h 1 31–37.

Venter ( Fig. 27B ). Striae mostly transverse, with longitudinal striae in pregenital region and on anal valves. Genital flap with a narrow band of arching transverse striae along anterior margin, longitudinal to oblique striae medially, and broad band of transverse striae along posterior margin. All ventral setae thin and smooth. Setae 1a, 3a and 4a shorter than distance between their bases respectively. Coxal setae count 2-1-1-1, one pair of pseudanal setae (ps 1), two pairs of smooth genital setae (g 1-2). Length of setae: 1a 35–50, 3a 38–47, 4a 38–49, ag 29–41, g 1 30–46, g 2 33–46, ps 1 16–29. Distances between setal bases: 1a–1a 46–70, 3a–3a 70–80, 4a–4a 98–119, ag–ag 33–39.

Gnathosoma ( Fig. 29A, 29C ). Stylophore with evenly rounded anterior margin and longitudinal striae (see Fig. 28 ). Ventral infracapitular setae m smooth, 21–25 in length. Palp setation and notation as shown in Figure 29A . Palptarsus: terminal eupathidium (suζ) club-like with blunt tip end, 3–4 long, two lateral eupathidia (ul′ζ and ul″ζ), ul′ζ 4.5–5.0 and ul″ζ 6–7.5 long, one solenidion (ω) 3–3.6 long; three short, smooth, tactile setae (a, b, c). Peritreme ending in small expansion ( Fig. 29C ).

Legs ( Fig. 30 ). Empodial claws absent. One set of duplex setae and one solenidion on tarsus I, solenidion ω′ 12–17, solenidion ω″ 18–20 long, single tc on tarsus I; tibia I with one solenidion φ 14–16 long; tarsi II one set of duplex setae, solenidion ω″ 14–17 long; tarsi III and IV without solenidion. Chaetotaxy of legs I–IV (eupathidia followed by solenidia in parentheses): trochanters 1-1-1-1, femora 6-4-2-1, genua 3-3-1-1, tibiae 5(0; 1)-4-3-3, tarsi 5(3; 2)-4(3; 1)-6-6. Legs I–IV setation and notation as shown in Figure 29 . Length of leg segments: femur I 100–121, genu I 45–54, tibia I 68–77, tarsus I 71–77; femur II 84–99, genu II 42–50, tibia II 58–65, tarsus II 67–76; femur III 79–92, genu III 35–42, tibia III 55–69, tarsus III 79–87; femur IV 90–101, genu IV 39–44, tibia IV 71–80, tarsus IV 80–93.

Male (n = 3)

Dorsum ( Figs 31–32 ). Idiosoma narrowing posteriorly. Length of idiosoma 248–285 excluding gnathosoma, 301–336 including gnathosoma, 156–188 wide. Integument with a pattern resulting in highly wrinkled ornamentation that irregular ridges. Prodorsum with 3 pairs of lanceolate setae on strong tubercle, covered stout barbs, v 2 24–25, sc 1 55–61 and sc 2 36–41. Distances between setal bases: v 2 – v 2 61–67, sc 1 – sc 1 85–86.

Hysterosoma with 11 pairs of setae (c 1–3, d 1 – 2, e 1–2, f 2, h 1–3). Dorsal central setae (c 1, d 1 and e 1) close to each other and c 2 near to c 3, f 1 and f 2 marginally positioned. Setae h 2–3 of differing morphology, similar to other ventral setae and inserted posterodorsally. Dorsal central setae c 1, d 1 and e 1 as long as the distance to setae in the next setal row. Length of setae: c 1 30–34, c 2 41–52, c 3 38–42, d 1 29–35, d 2 38–46, e 1 28 –33, e 2 29 –36, f 1 30–33, f 2 21–23, h 1 22–24, h 2 11–15, h 3 12–13. Distances between setal bases: c 1 – c 1 15–18, d 1 – d 1 23–28, e 1 – e 1 15 –20, f 1 – f 1 53–57, h 1 – h 1 17–18.

Venter. Striae mostly transverse and opisthosoma with wide space striae. All ventral setae thin and smooth. Setae 1a, 3a and 4a shorter than distance between their bases respectively. Coxal setae count 2-1-1-1, one pairs of pseudanal setae (ps 1), two pairs of smooth genital setae (g 1-2). Length of setae: 1a 27–54, 3a 27–40, 4a 24–34, ag 19–20, g 1 10–13, g 2 10–13, ps 1 9–11. Distances between setal bases: 1a–1a 36–40, 3a–3a 49–56, 4a–4a 60–64, ag–ag 9–20.

Gnathosoma ( Figs 29B, 29D ). Stylophore with round anterior margin and longitudinal striae. Ventral infracapitular setae m smooth, 24–27 in length. Palp setation and notation as shown in Figure 29B . Palptarsus: terminal eupathidium (suζ) stout with blunt tip end, 1.4–1.9 long, two lateral eupathidia (ul′ζ and ul″ζ), ul′ζ 5–5 and ul″ζ 8–8 long, one solenidion (ω) 3–3.9 long; three short, smooth, tactile setae (a, b, c). Peritreme ending in small expansion ( Fig. 29D ).

Aedeagus ( Figs 29E–G , 33 ). Aedeagus gradually narrowing and bent distally to form a somewhat S shape.

Legs ( Fig. 34 ). Empodial claws absent. One pairs of duplex setae and four solenidia on tarsus I, solenidion ω′ 16–17, ω″ 1 13–15 long, ω″ 14–21 long, ω′ 2 13–16, ω″ 2 14–15. single tc present; tibia I with four solenidion, φ 16–17, φ′ 14–17, φ" 13–14, φ" 1 13–14 long; tarsi II with one duplex setae, solenidion ω″ 15–19 long, solenidion ω′ 13–14, ω″ 1 14–15 long; tibia II with four solenidion in one male and three solenidion in two males (φ" 1 missing), φ 13–14, φ′ 13–15, φ" 12 (n = 1), φ" 13–3 long; tarsi III with one solenidion ω′ 13–15; tarsi IV with one proximal solenidion ω′ 11–134 long. Number of tactile setae on leg (I–IV) segments: trochanters 1-1-1-1, femora 7 or 8 or 9-6-3-1, genua 3-3-2-2, tibiae 6-4-3-3, tarsi 6-3-7-7. Number of eupathidia on tarsi I-V: 3-3-0-0. Legs I–IV setation and notation as shown in Figure 34 . Length of leg segments: femur I 81–141, genu I 65–69, tibia I 103–108, tarsus I 87–89; femur II 105–116, genu II 59–63, tibia II 92–93, tarsus II 82–83; femur III 105–106, genu III 48–48, tibia III 93–99, tarsus III 92–102; femur IV 103–120, genu IV 53–53, tibia IV 92–113, tarsus IV 78–101.

Remarks

A. firmianae was erected based on one pair of pseudanal setae and lanceolate dorsal setae by Ma & Yuan (1965). Although they pointed out that one pair of pseudanal setae is a new character for the Tetranychidae , A. firmianae was placed into the genus Eutetranychus Banks in the original description. The setal counts of male and female tarsi I described here are the same as those of Ehara’s (1980) description.

The setal count of male femur I is seven in Ma’s description (Ma & Yuan 1964, Ma et al. 1984), while this study shows one in four males femur I with seven setae, one in four males femur I with eight setae, one in four males femur I with seven setae in left side and nine setae in right side. and one in four males femur I with seven setae in left side and eight setae in right side. Ehara (1980) argued that seven to nine setae (usually seven) are present on male femur I.

Figures

FIGURE 27 Aponychus firmainae. Female, A, dorsum; B, genital and anal area.

FIGURE 28 Aponychus firmainae. Photograph. Female: dorsal view of idiosoma.

FIGURE 29 Aponychus firmainae.A, female, palp, lateral-ventral view; B, male, palp, lateral-dorsal view; C, female, peritreme; D, male, peritreme, E–G, aedeagus.

FIGURE 30 Aponychus firmainae. Female, A–D, left side legs I–IV, respectively.

FIGURE 31 Aponychus firmainae. Male: dorsum.

FIGURE 32 Aponychus firmainae. Photograph. Male: dorsal view of idiosoma.

FIGURE 33 Aponychus firmainae. Photographs. Male: A–B, aedeagus.

FIGURE 34 Aponychus firmainae. Male: A–D, left side legs I–IV, respectively.