Phytoseiidae (Acari: Mesostigmata) is a well-known mite family, and more than 2,700 species have been recorded worldwide. Prior this study, 64 phytoseiid species had been recorded in main island of Taiwan and its neighboring islands. Nevertheless, many areas are still unexplored and need further investigation, such as the Penghu Islands. The present study was based on phytoseiid mite materials collected from the Penghu Islands in 1989 and 2020. A list of identified phytoseiid mites is provided herein, 16 species, eight genera, and three subfamilies. Proprioseiopsis penghuensis sp. nov. and Neoseiulus xiaomenensis sp. nov. are new to science, and Amblyseius cinctus Corpuz-Raros & Rimando, A. fletcheri Schicha, Phytoseius rachelae Swirski & Shechter are new records for the country. The further comprehensive phytoseiid investigation in Penghu Islands is needed for exploring the relationships among environmental and agricultural changes, and phytoseiid mites.
Introduction
The Penghu (Pescadores) Islands are an archipelago of 90 islands in the Taiwan Strait. The largest island has an area of 65 km2 (Fig. 1). Summers in Penghu are hot and dry, but winters are cold with strong winds (Hsu 2005). Farmlands are usually surrounded by walls made of coral stones for protection. The soil of Penghu is rich in salinity and poor in fertility; thus, agricultural development is limited. Population aging and migration are serious problems, and most farmland is fallow. Additionally, the exotic plant Leucaena leucocephala (Fabaceae) has invaded these islands and become a serious concern (Wei et al. 2020).
The main island of Taiwan is neighbored by many islands, such as Lanyu Island, Green Islands, and the Penghu Islands. Little is known about the mite fauna, except ticks (Robbins 2005), chigger mites (Chuang et al. 2015), and a species of podapolipid mites on a locust species (Lo 1990), of the Penghu Islands. Knowledge of the taxonomy of species of phytoseiid mites has grown considerably over the last 30 years due to their use as biological control agents worldwide (Huffaker et al. 1970; McMurtry et al. 1970, 2013). To date, more than 90 genera and 2,700 species have been recorded worldwide (Demite et al. 2020), but little is known about the distribution of this mite family in some areas. According to Liao et al. (2020), 64 phytoseiid species have been recorded in Taiwan and neighboring islands; however, nothing is known in the Penghu Islands.
In this study, we present the results of phytoseiid mite collections in the Penghu Islands from 1989 to date. In total, 16 species are reported, including two new species: Proprioseiopsis penghuensis sp. nov. and Neoseiulus xiaomenensis sp. nov.. Identification key for phytoseiid species found in the Penghu Islands is proposed.
Materials and Methods
Mite specimens examined in this study were collected from various plants and soils from the Penghu Islands in 1989 and 2020 (Fig. 2). Specimens were mounted in Hoyer's medium. Additionally, old specimens in poor condition were soaked with water at least one day, clean by lactic acid, bleached by high concentration (50%) H2O2 in the blacken specimen, rinsed in ethanol (75%), and remounted in Hoyer's medium (Yeh et al. 2008). Specimens were examined under Olympus BX51 microscope, and measurements taken using a stage-calibrated ocular micrometers and as well as ImageJ 1.47 (Schneider et al. 2012). All measurements were provided in micrometers (µm), holotype measurements are shown in boldface type for the specimens, followed by their mean and range in parenthesis. The dorsal shield lengths were measured from anterior to posterior margins along the midline and widths measured at j6 and S4 level. The sternal shield lengths and widths were taken from anterior to posterior margin along the midline and at broadest level, respectively. The genital shield widths were taken from broadest level. The ventrianal shield lengths were taken from anterior to posterior margins along the midline and ZV2 and anus levels. The general terminology used for morphological descriptions in this study follows that of Chant & McMurtry (2007). The notation for idiosomal setae follows that of Lindquist & Evans (1965) and Lindquist (1994), as adapted by Rowell et al. (1978) and Chant & Yoshida-Shaul (1992). The notation for gland pores and poroids is based on Athias-Henriot (1975). Specimens were deposited in the following institutions: five females of Typhlodromus (Anthoseius) obesus in NMNS (National Museum of Natural Science, Taichung, Taiwan), collection data #1 to #19 in TARL (Taiwan Acari Research Laboratory, Taichung City, Taiwan), collection data #20 to #30 in NTU (Department of Entomology, National Taiwan University, Taipei, Taiwan), type specimens were deposited based on the specimens examined section, respectively. If necessary, the locality names were translated using the Geographic Name Information System, Department of Land Administration, Ministry of the Interior (Taiwan) ( http://gn.moi.gov.tw/geonames/Translation/Translation.aspx). The map of the Penghu Islands was prepared using the Quantum GIS (QGIS Development Team 2020), based on the label data of examined material in this study.
Result
Collection data (Figure 1)
#1—Lintou, Huxi Township, Penghu County, Achyranthes obtusifolia (Amaranthaceae), 21 Apr 1989, C. C. Ho.
##2—Lintou Park, Huxi Township, Penghu County, Euphorbia heterophylla (Euphorbiaceae), 21 Apr 1989, C. C. Ho.
##3—Lintou Park, Huxi Township, Penghu County, Lantana camara (Verbenaceae), 21 Apr 1989, C. C. Ho.
##4—Baisha Township, Penghu County, Achyranthes obtusifolia (Amaranthaceae), 21 Apr 1989, C. C. Ho.
##5—Baisha Township, Penghu County, Cirsium japonicum (Asteraceae), 21 Apr 1989, C. C. Ho.
##6—Chengqian Village, Baisha Township, Penghu County, Xanthium strumarium (Asteraceae), 21 Apr 1989, C. C. Ho.
##7—Xiaomen Village, Xiyu Township, Penghu County, Penghu, soil, 21 Apr 1989, C. C. Ho.
##8—Xiaomen Village, Xiyu Township, Penghu County, Penghu, unknown plant, 21 Apr 1989, C. C. Ho.
##9—Chengqian Village, Baisha Township, Penghu County, Anagallis arvensis (Primulaceae), 21 Apr 1989, C. C. Ho.
##10—Chengqian Village, Baisha Township, Penghu County, soil, 21 Apr 1989, C. C. Ho.
##11—Wai'an Village, Xiyu Township, Penghu County, Achyranthes obtusifolia (Amaranthaceae), 21 Apr 1989, C. C. Ho.
##12—Wai'an, Xiyu Township, Penghu County, Macaranga tanarium (Euphorbiaceae), 21 Apr 1989, C. C. Ho.
##13—Fenggui, Magong City, Penghu County, Oxalis corniculata (Oxalidaceae), 22 Apr 1989, C. C. Ho.
##14—Lintou Park, Huxi Township, Penghu County, Achyranthes obtusifolia (Amaranthaceae), 22 Apr 1989, C. C. Ho.
##15—Lintou Park, Huxi Township, Penghu County, Chloris barbata (Gramineae), 22 Apr 1989, C. C. Ho.
##16—Xiaomen Village, Xiyu Township, Penghu County, wilt weed, 22 Apr 1989, C. C. Ho.
##17—Chengqian Village, Baisha Township, Penghu County, Achyranthes obtusifolia (Amaranthaceae), 22 Apr 1989, C. C. Ho.
##18—Chengqian Village, Baisha Township, Penghu County, soil, 22 Apr 1989, C. C. Ho.
##19—Wai'an Village, Xiyu Township, Penghu County, unknown plant, 22 Apr 1989, C. C. Ho.
##20—Yuwengdao Lighthouse, Wai'an Village, Xiyu Township, Penghu County (N 23°33.766′E 119°28.150′, 47m), Bidens pilosa (Asteraceae), 13 Jan 2020, J. R. Liao.
##21—Wai'an Village, Xiyu Township, Penghu County (N 23°33.916′E 119°29.166′, 43m), Broussonetia papyrifera (Moraceae), 13 Jan 2020, J. R. Liao.
##22—Wai'an Village, Xiyu Township, Penghu County (N 23°33.916′E 119°29.166′, 43m), Mallotus japonicus (Euphorbiaceae), 13 Jan 2020, J. R. Liao.
##23—Nei'an Village, Xiyu Township, Penghu County (N 23°34.233′E 119°29.650′, 11m), Hibiscus tiliaceus (Malvaceae), 13 Jan 2020, J. R. Liao.
##24—Dream Beach, Xiyu Township, Penghu County (N 23°36.733′E 119°30.550′, 9m), Hibiscus tiliaceus (Malvaceae), 13 Jan 2020, J. R. Liao.
##25—North Sea Visitor Center, Baisha Township, Penghu County (N 23°40.166′E 119°36.083′, 10m), Glebionis coronaria (Asteraceae), 13 Jan 2020, J. R. Liao.
##26—Lintou Park, Huxi Township, Penghu County (N 23°33.433′E 119°38.400′, 6m), Artemisia argyi (Asteraceae), 13 Jan 2020, J. R. Liao.
##27—Lintou Park, Huxi Township, Penghu County (N 23°33.433′E 119°38.400′, 6m), Hibiscus tiliaceus (Malvaceae), 13 Jan 2020, J. R. Liao.
##28—Longmen Beach, Huxi Township, Penghu County (N 23°33.916′E 119°40.883′, 6m), Hibiscus tiliaceus (Malvaceae), 16 Jan 2020, J. R. Liao.
##29—Longmen Beach, Huxi Township, Penghu County (N 23°33.916′E 119°40.883′, 6m), unknown plant, 16 Jan 2020, J. R. Liao.
##30—Shanshuei, Magong City, Penghu County (N 23°30.800′E 119°35.366′, 6m), Hibiscus tiliaceus (Malvaceae), 16 Jan 2020, J. R. Liao.
A list of identified phytoseiid mites during Penghu surveys*
*Numbers indicate locations where species was collected.
Amblyseius cinctus #5, #8, #9, #13
Amblyseius eharai #2, #3, #6, #12, #16#19 #22 #25
Amblyseius fletcheri #20 #29
Euseius ovalis #22
Neoseiulus barkeri #8, #11, #18, #19
Neoseiulus xiaomenensis sp. nov. #7
Neoseiulus womersleyi #13
Scapulaseius cantonensis #23
Paraphytoseius orientalis #23 #24 #26 #27 #28 #30
Proprioseiopsis penghuensis sp. nov. #5, #9, #15
Phytoseius rachele #1, #4, #5, #9, #11, #14, #17
Phytoseius coheni #3 #24 #28 #29
Phytoseius hongkongensis #21
Typhlodromus (Anthoseius) obesus #15
Typhlodromus (Anthoseius) neocrassus #15
Typhlodromus (Anthoseius) serrulatus#16
Key to phytoseiid species from the Penghu Islands based on adult females
1. Setae z3 and s6 absent 2
- Either or both of setae z3 and s6 present 11
2. Setae JV2 and ZV2 forward migrate to a row Euseius ovalis
- Setae JV2 and ZV2 locate in normal position 3
3. Setae S4 absent Paraphytoseius orientalis
- Setae S4 present 4
4. Ratio seta s4:Z1 > 3.0:1.0 5
- Ratio seta s4:Z1 < 3.0:1.0 8
5. Setae J2 absent Proprioseiopsis penghuensis sp. nov.
- Setae J2 present 6
6. Ventrianal shield pentagonal Amblyseius cinctus
- Ventrianal shield vase-shaped 7
7. Posterior margin of sternal shield with median projection Amblyseius eharai
- Posterior margin of sternal shield straight Amblyseius fletcheri
8. Genua II and III with macrosetae Scapulaseius cantonensis
- Genua II and III without macroseta 9
9. Leg IV with three macrosetae Neoseiulus xiaomenensis sp. nov.
- Leg IV with only one macroseta 10
10. Setae j5, j6 and J2 longer than distance to base of j6, J2 and Z4 Neoseiulus womersleyi
- Setae j5, j6 and J2 shorter than distance to base of j6, J2 and Z4 Neoseiulusbarkeri
11. Setae Z1, S2, S4 and S5 absent 12
- At least one of above mentioned setae present 14
12. Setae J2 and R1 present Phytoseius hongkongensis
- Setae J2 and R1 absent 13
13. Setae s4 much longer than s6 Phytoseius rachelae
- Setae s4 approximately as long as s6 Phytoseius coheni
14. Sternal shield with three pairs of setae Typhlodromus (Anthoseius) serrulatus
- Sternal shield with two pairs of setae 15
15. Movable digit of chelicera with one tooth Typhlodromus (Anthoseius) obesus
- Movable digit of chelicera with three teeth Typhlodromus (Anthoseius) neocrassus
Proprioseiopsis penghuensis Liao & Ho sp. nov.
(Figures 3–10)
Diagnosis
Female dorsal shield smooth, except some patches of reticulations visible laterally, and slightly reticulated in central part of podosoma, bearing 18 pairs of dorsal setae (including r3 and R1). All setae smooth, except Z4 and Z5 slightly serrated. Seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9) visible on dorsal shield. Peritreme extending to j1 level. Sternal shield with three pairs of setae; ventrianal shield pentagonal, bearing three pairs of pre-anal setae, with small and rounded gland pore gv3. Fixed digit of chelicera with three teeth; movable digit with one tooth. Calyx of spermatheca bell-shaped. Leg IV with three macrosetae; genu II with eight setae.
Female (n=3)
A lightly sclerotized mite. Idiosomal setal pattern: 10A:8E/JV-3:ZV.
Dorsal idiosoma (Figure 3). Dorsal shield smooth, laterally reticulated, central part of podosoma slightly reticulated; 364 356 (346–364) long (j1–J5 level) and 257 251 (243–257) wide at level of j6, 231 233 (229–237) wide at level of S4; seven pairs of gland pores on dorsal shield (gd1, gd2, gd4, gd5, gd6, gd8, gd9), twelve pairs of poroids (id1, id2, id4, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of setae: j1 22 22 (21–23), j3 51 48 (46–51), j4 4 5 (4–7), j5 5 5 (5–6), j6 11 7 (5–11), J5 9 10 (9–11), z2 24 24 (19–29), z4 37 35 (35–37), z5 5 5 (4–6), Z1 13 16 (13–17), Z4 64 64 (64–64), Z5 66 65 (64–67), s4 63 61 (56–64), S2 22 24 (22–26), S4 16 18 (16–21), S5 19 18 (15–20), r3 14 16 (14–19), R1 19 16 (14–19). All setae smooth, except for Z4 and Z5 slightly serrated. Peritreme extending to j1 level; peritremal shield with one pair of gland pores (gd3), and one pair of poroids (id3).
Ventral idiosoma (Figure 4). Sternal shield smooth, much wider than long, posterior margin concave, 61 60 (57–62) long, 95 98 (95–99) wide, and with three pairs of setae st1 28 32 (28–36), st2 23 26 (23–29), st3 26 23 (20–26), and two pairs of poroids (iv1, iv2). Exopodal shield at coxae I–IV. Metasternal platelets tear-shaped, with one pair of metasternal setae, st4 26 26 (22–29), with one pair of poroids (iv3). Genital shield reticulated, posteriorly truncate, 91 95 (91–99) wide at level of genital seta, st5 20 26 (20–30). Distances between st1-st1 51 53 (51–57), st2-st2 69 70 (69–72), st3-st3 83 80 (78–83), st1-st3 59 60 (59–62), st5-st5 82 83 (79–89). Ventrianal shield pentagonal, reticulated, 107 115 (107–119) long, 118 118 (115–121) wide at level of ZV2, 76 79 (76–83) wide at level of anus; with three pairs of pre-anal setae, JV1 23 23 (21–25), JV2 26 26 (24–27), ZV2 25 24 (23–25), Pa 13 14 (13–16), Pst 21 21 (21–22) on shield. Setae JV4 14 13 (13–14), JV5 51 49 (48–51), ZV1 24 22 (21–24), ZV3 14 14 (13–15) on interscutal membrane. All setae smooth. Two pairs of metapodal platelets: primary platelet 19 23 (19–26) long, secondary platelet 5 6 (5–7) wide; 11 10 (9–11) long, 1 1 (1–2) wide.
Chelicera (Figure 5). Movable digit 28 28 (28–28) long, with one tooth; fixed digit 27 28 (26–29) long, anterior half with three teeth, with pilus dentilis.
Spermatheca (Figure 6). Calyx bell-shaped, 11 12 (11–13) long, 11 14 (11–17) wide; atrium nodular incorporated within calyx, major duct long, minor duct visible.
Legs (Figures 7–10). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 2-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge IV (ad2) 45 39 (34–45), Sti IV (ad) 25 24 (22–25), St IV (d) 61 64 (61–68). Macrosetae setiform.
Type specimens
Holotype: one female (89-Am-0964) from #5 (TARL). Paratypes: one female (89-Am-0987) from #9 (NMNS); one female (89-Am-0985) from #15 (NTU).
Etymology
The epithet penghuensis refers to the Penghu Island, that type material of this species were collected.
Remarks
The new species was compared with all known species of the genus Proprioseiopsis. The species belongs to the belizensis subspecies of the belizensis species group as genu I without macroseta and spermatheca with calyx bell-shaped. Within the subgroup, it exhibits a close affinity to P. basis Karg, P. beatus (Chaudhri), P. campanulus Karg, P. exitus (Schuster), P. exopodalis (Kennett), P. fragariae (Kennett), P.lineatus (Wu & Lan), P. marginatus Denmark, P. mauiensis (Prasad), P. okanagensis (Chant), P. ovatus (Garman), P. phaseoloides Denmark & Evans, P. poculus Tuttle & Muma, P. reventus (Zack), P. rosellus (Chant), P. rotundus (Muma), P. weintraubi (Chant & Hansell) based on dorsal setae S2, Z4, Z5 length not extremely long. The differences between P. penghuensis sp. nov. and related species are given in Table 1. In addition, P. lineatus and P. okanagensis are most resembling species to the new species. The new species differs from P. lineatus by having z2<z4 (vs. z2>z4 in P. lineatus), and length of Z4 and Z5 about 65 (vs. about 80 and 100, respectively, in P. lineatus). Also, the new species differs from P. okanagensis in length of z2, z4, s4, S2, Z4, and Z5 (24, 37, 63, 22, 64, and 66 as oppose to 36, 62, 82, 40, 80, and 106 in P. okanagensis).
FIGURE. 3–6.
Proprioseiopsis penghuensis sp. nov., female. 3. Dorsal shield; 4. Ventral idiosoma; 5. Chelicera; 6. Spermatheca.
FIGURE. 7–10.
Proprioseiopsis penghuensis sp. nov., female, legs (trochanter–basitarsus). 7. Leg I; 8. Leg II; 9. Leg III; 10. Leg IV.
Neoseiulus xiaomenensis Liao & Ho sp. nov.
(Figures 11–25)
Diagnosis
Female dorsal shield reticulated, bearing 19 pairs of dorsal setae (including r3, R1). All setae smooth, except Z4, Z5 serrated. Six pairs of gland pores (gd1, gd4, gd5, gd6, gd8, gd9) visible on dorsal shield. Peritreme extending to j1-j3 level. Sternal shield with three pairs of setae; ventrianal shield pentagonal, bearing three pairs of pre-anal setae, with crescentic gland pore gv3. Fixed digit of chelicera with four teeth; movable digit with three teeth. Calyx of spermatheca bell-shaped; atrium connect to calyx with neck. Leg IV with three pairs of macrosetae; genu II with eight setae.
Female (n=5)
A slightly sclerotized mite. Idiosomal setal pattern: 10A:9B/JV-3:ZV.
Dorsal idiosoma (Figure 11). Dorsal shield reticulated, 364 356 (346–364) long (j1–J5 level) and 172 168 (162–174) wide at level of s4, 179 175 (167–180) wide at level of S4; six pairs of gland pores (gd1, gd4, gd5, gd6, gd8, gd9), fourteen pairs of poroids (id1, id1a, id2, id4, id6, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of dorsal setae: j1 22 21 (17–24), j3 42 42 (32–50), j4 34 32 (30–35), j5 34 34 (34–34), j6 39 42 (39–46), J2 ? 47 (41–53), J5 10 11 (9–12), z2 39 36 (33–39), z4 44 42 (40–44), z5 25 26 (25–26), Z1 47 50 (46–55), Z4 62 63 (62–64), Z5 82 83 (82–86), s4 50 53 (48–61), S2 48 57 (48–65), S4 42 44 (40–49), S5 35 36 (32–44), r3 29 28 (26–31), R1 29 26 (22–32). All setae smooth, setiform, except Z4 and Z5 slightly serrated. Peritreme extending to j1 level; peritremal shield smooth, with one pair of gland pores (gd3), and one pair of poroids (id3).
Ventral idiosoma (Figure 12). Sternal shield reticulated, posterior margin almost straight; 70 67 (65–70) long, 84 79 (75–84) wide at level of st3, with three pairs of setae st1 28 27 (26–28), st2 27 26 (23–27), st3 19 22 (19–24), and two pairs of poroids (iv1, iv2). Metasternal platelets tear-shaped, with a pair of metasternal setae, st4 18 20 (18–23), one pair of poroids (iv3). Genital shield reticulated, truncate posteriorly, with one pair of genital setae st5 19 21 (19–21), 80 75 (67–80) wide at level of genital setae. Exopodal shield at coxae II–IV. Distances between st1-st1 51 47 (44–51), st2-st2 54 56 (54–57), st3-st3 75 69 (63–75), st1-st3 58 61 (58–67), st5-st5 68 64 (61–68). Ventrianal shield reticulated, pentagonal, 119 117 (111–122) long, 101 100 (98–102) wide at ZV2 level, 74 69 (65–74) wide at level of anus; with three pairs of preanal setae, JV1 17 17 (15–20), JV2 15 16 (14–19), ZV2 13 13 (13–13), one pair of para-anal; Pa 15 15 (14–15), Pst 14 17 (14–19) on shield; gland pore gv3 crescentic. Setae ZV1 11 15 (11–18), ZV3 13 13 (11–14), JV4 13 15 (13–16), JV5 55 55 (50–60) on interscutal membrane. All setae smooth, setiform. Two pairs of metapodal platelets: primary platelet 23 24 (23–26) long, 5 4 (2–5) wide; secondary platelet 12 12 (11–13) long, 3 2 (1–3) wide.
Chelicera (Figure 13). Movable digit 22 21 (19–23) long, with three teeth; fixed digit 24 21 (20–24) long, with four teeth, with pilus dentilis.
Spermatheca (Figure 14). Calyx bell-shaped, 10 10 (8–13) long, 8 9 (8–10) wide; atrium connect to calyx with neck, major duct and minor duct visible.
Legs (Figures 15–18). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): leg I, 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/ 1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 2-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge IV (ad2) 25 27 (24–30), Sti IV (ad) 29 31 (25–37), St IV (d) 53 54 (49–61). Macrosetae setiform. Male (n=1)
Idiosomal setal pattern: 10A:9B/JV-3,4:ZV-1,3.
Dorsal idiosoma (Figure 19). Dorsal shield reticulated, 295 long (j1-J5 level) and 183 wide at level of j6, 158 wide at level of S4; six pairs of gland pores (gd1, gd4, gd5, gd6, gd8, gd9), fourteen pairs of poroids (id1, id1a, id2, id4, id6, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of setae: j1 17, j3 31, j4 24, j5 26, j6 25, J2 40, J5 8, z2 28, z4 34, z5 22, Z1 42, Z4 60, Z5 70, s4 38, S2 45, S4 38, S5 28, r3 29, R1 22. All setae smooth, except Z5 slightly serrated. Setae r3 and R1 inserted on dorsal shield. Peritreme extending beyond j3 level; peritremal shield smooth
Ventral idiosoma (Figure 20). Sternogenital shield lateral slightly reticulated, longer than wide, 120 long, 77 wide at level of st2, with five pairs of setae, st1 20, st2 16, st3 14, st4 13, st5 15, three pairs of poroids (iv1, iv2, iv3). Exopodal shield at coxae II–IV. Distances between st1–st1 45, st2–st2 53, st3–st3 57, st4–st4 52, st5–st5 38, st1–st5 109. Ventrianal shield subtriangular, reticulated, 120 long and 165 wide at level of anterior corner, 70 wide at level of anus, not fused with peritremal shield; with three pairs of preanal setae, JV1 9, JV2 8, ZV2 13; gland pore gv3 crescentic; Pa 8, Pst 8 on shield. Setae JV5 30 on interscutal membrane.
Chelicera (Figure 21). Movable digit 19 long, with one tooth. Fixed digit 18 long, with one tooth, with pilus dentilis; spermatodactyl heel-and-toe variant, shaft 13 long, heel rounded, foot 8 long.
Legs (Figures 22–25). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): leg I, 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/ 1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 2-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge IV (ad2) 19, Sti IV (ad) 26, St IV (d) 47. Macrosetae setiform.
Type specimens
Holotype: one female (89-Am-92) from #7 (NTU). Paratypes: seven females one male (89-Am-0966, 1059, 60, 61, 64, 67, 68) from #7 (NMNS, NCHU, TARL).
Etymology
The epithet xiaomenensis refers to Xiaomen, the village that type material of this species were collected.
Remarks
The new species was compared with all species of the cucumeris species subgroup in the genus Neoseiulus for identification. It shows a close affinity to 16 known species, N. aegyptocitri (Kandeel & El-Halawany), N. anonymus (Chant & Baker), N. argillaceus (Kolodochka & Bondarenko), N. bayviewensis (Schicha), N. bellinus (Womersley), N. crataegi (Jorgensen & Chant), N. curvus (Wu & Li), N. esculentus (El-Badry), N. fallacis (Garman), N. fallacoides Tuttle & Muma, N. idaeus Denmark & Muma, N. imbricatus (Corpuz & Rimando), N. lamticus (Athias-Henriot), N. malaban Beard, N. placitus (Khan & Chaudhri), N. tarapacensis Peralta, and most based on the longer dorsal setae, ventrianal shield pentagonal, calyx of spermatheca bell-shaped, and they were considered as “N. fallacis appearance”. These species are different in the relative lengths of dorsal setae. The differences between N. xiaomenensis sp. nov. and related species are given in Table 2. Neoseiulus fallacis and N. imbricatus which seems most close to the new species, but the new species differs from N. fallacis in spermatheca with neck (vs. without neck in N. fallacis), and lengths of setae z2, z4, Z1, S2, S4, and S5 (39, 44, 47, 48, and 42 as oppose to 47, 51, 57, 66 and 54 in N. fallacis). Additionally, the new species differs from N. imbricatus in length of seta S5 about 35 (vs. 55 in N. imbricatus), posterior margin of sternal shield straight (vs. with a median projection in N. imbricatus).
FIGURE. 11–14.
Neoseiulus xiaomenensis sp. nov., female. 11. Dorsal shield; 12. Ventral idiosoma; 13. Chelicera; 14. Spermatheca.
FIGURE. 15–18.
Neoseiulus xiaomenensis sp. nov., female, legs (trochanter–basitarsus). 15. Leg I; 16. Leg II; 17. Leg III; 18. lLeg IV.
FIGURE. 19–21.
Neoseiulus xiaomenensis sp. nov., male. 19. Dorsal shield; 20. Ventral idiosoma; 21. Chelicera and spermatodactyl.
FIGURE. 22–25.
Neoseiulus xiaomenensis sp. nov., male, legs (trochanter–basitarsus). 22. Leg I; 23. Leg II; 24. Leg III; 25. Leg IV.
Amblyseius cinctus Corpuz & Rimando, 1966
Amblyseius cinctus Corpuz & Rimando, 1966: 119
(Figures 26–40)
Female (n=2)
A lightly sclerotized mite. Idiosomal setal pattern: 10A:9B/JV-3:ZV.
Dorsal idiosoma (Figure 26). Dorsal shield, smooth, 327 (316–338) long, 216 (214–219) wide at level of s4, 209 (201–217) wide at level of S4; seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9), twelve pairs of poroids (id1, id2, id4, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of dorsal setae: j1 25 (21–28), j3 41 (36–46), j4 10 (9–11), j5 11 (10–12), j6 8 (7–10), J2 9 (8–10), J5 9 (8–10), z2 10 (8–12), z4 10 (8–11), z5 9 (8–9), Z1 10 (10–11), Z4 93 (86–101), Z5 226 (210–242), s4 80 (73–88), S2 11 (10–12), S4 10 (9–11), S5 9 (8–11), r3 9 (9–10), R1 10 (8–12). Setae j1, j3, s4 longer and smooth; Z4, Z5 greatly elongated, slightly serrated; other minute. Peritreme extending beyond to j1, peritremal shield smooth, lightly sclerotized, with one pair of gland pores (gd3) and one pair of poroids (id3).
Ventral idiosoma (Figure 27). Sternal shield lateral slightly reticulated, posterior margin straight, wider than long, 71 (67–74) long, 88 (84–92) wide at st3 level, with three pairs of setae st1 27 (27–27), st2 25 (23–27), st3 24 (23–25) and two pairs of poroids (iv1, iv2). Exopodal shield at coxae II–IV. Metasternal platelets tear-shaped, with a pair metasternal setae, st4 20 (19–21), and one pair of poroids (iv3). Genital shield smooth, with one pair of genital setae st5 20 (18–21), 74 (69–78) wide at level of genital setae. Distance between st1–st1 52 (49–54), st2–st2 64 (58–70), st3–st3 69 (68–70), st1–st3 61 (61–62), st5–st5 65 (59–71). Ventrianal shield smooth, pentagonal; 103 (102–103) long, 87 (79–95) wide at level of ZV2 and 71 (69–72) wide at level of anus; with three pairs of pre-anal setae, JV1 16 (15–16), JV2 17 (14–20), ZV2 11 (10–12), gland pore gv3 crescentic, Pa 13 (12–14), Pst 13 (12–15). Setae JV4 12 (11–13), JV5 76 (71–82), ZV1 14 (13–16), ZV3 11 (9–12) on interscutal membrane. All ventral setae smooth. Two pairs of metapodal platelets: primary platelet 19 (19–20) long, 6 (6–6) wide; secondary platelet 10 (10–11) long, 2 (1–2) wide.
Chelicera (Figure 28). Movable digit 30 (29–30) long, with three teeth; fixed digit 30 (29–30) long, with eleven teeth, with pilus dentilis.
Spermatheca (Figure 29). Calyx tubular, 9 (8–11) long, 3 (3–3) wide; atrium incorporate with calyx, minor and major ducts visible.
Legs (Figures 30–33). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): leg I, 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/ 1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge I (pd2) 41 (39–44), Sge II (pd2) 29 (29–30), Sge III (ad2) 60 (58–62), Sti III (ad) 44 (44–44), Sge IV (ad2) 102 (100–105), Sti IV (ad) 70 (67–72), St IV (d) 80 (80–80). Macrosetae setiform.
Male (n=2)
A lightly sclerotized mite. Idiosomal setal pattern: 10A:9B/JV-3,4:ZV-1,3.
Dorsal idiosoma (Figure 34). Dorsal shield smooth, anterolaterally reticulated; 258 (250–266) long, 188 (184–192) wide at level of s4, 156 (142–169) wide at level of S4, with seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9), twelve pairs of poroids (id1, id2, id4, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of setae: j1 19 (19–19), j3 41 (37–46), j4 7 (7–7), j5 6 (5–6), j6 6 (5–7), J2 5 (4–6), J5 7 (6–8), z2 6 (5–6), z4 7 (5–9), z5 5 (4–6), Z1 6 (5–7), Z4 81 (73–89), Z5 191 (191–191), s4 62 (58–67), S2 6 (6–6), S4 6 (6–7), S5 6 (6–6), r3 10 (9–10), R1 9 (8–10). Setae j1, j3, s4 longer and smooth; Z4, Z5 greatly elongated, slightly serrated; other minute. Setae r3 and R1 inserted on dorsal shield. Peritreme extending to j1 level; peritremal shield lightly sclerotized.
Ventral idiosoma (Figure 35). Sternogenital shield smooth, lateral slightly reticulated, posterior margin almost straight, longer than wide 117 (115–119) long, 79 (79–80) wide at level st2, with five pairs of setae st1 21 (20–23), st2 19 (17–20), st3 20 (17–23), st4 13 (12–13), st5 13 (13–14), three pairs of poroids (iv1, iv2, iv3). Exopodal shield at coxae II–IV. Distance between st1-st1 50 (50–51), st2-st2 57 (55–59), st3-st3 52 (52–53), st4-st4 45 (43–47), st5-st5 34 (33–34), st1-st5 102 (101–104). Ventrianal shield subtriangular, reticulated, 110 (108–111) long, 141 (138–144) wide at level of anterior corner and 47 (46–49) wide at level of anus, fused with peritremal shield cingulum; with three pairs of pre-anal setae, JV1 12 (11–13), JV2 10 (10–10), ZV2 9 (9–9), gland pore gv3 crescentic, Pa 9 (7–11), Pst 11 (11–12) on shield; JV5 34 (34–34) on interscutal membrane. All ventral setae smooth.
Chelicera (Figure 36). Movable digit 18 (17–18) long, with one tooth; fixed digit 20 (20–20), with eight teeth, with pilus dentilis; spermatodactyl heel-and-toe variant, shaft 14 (14–15) long, heel rounded, foot 13 (12–13) long.
Legs (Figures 37–40). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): leg I, 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/ 1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge I (pd2) 31 (30–32), Sge II (pd2) 28 (28–29), Sge III (ad2) 36 (35–37), Sti III (ad) 34 (33–36), Sge IV (ad2) 66 (64–68), Sti IV (ad) 48 (48–49), St IV (d) 58 (56–60). Macrosetae setiform.
Specimens examined
Two females (89-Am-0963, 65) from #5 (TARL); one female and two males (89-Am-0989, 90, 1052) from #8 (TARL); one female and one male (89-Am-0986, 92) from #9 (TARL); one female (89-Am-1051) from #13 (TARL).
Distribution
Asia: China (Chen et al. 1980), Malaysia (Ehara 2002), Philippines (Corpuz & Rimando 1966), Singapore (Corpuz-Raros 1995), Taiwan [Penghu island (present study)], Thailand (Ehara & Bhandhufalck 1977), Vietnam (Kreiter et al. 2020);
Remarks
Corpuz & Rimando (1966) described this species on Panicum pilipes (Poaceae) in the Philippines. The second author of present study collected individuals on three different plant families, namely Asteraceae, Primulaceae, and Oxalidaceae. We compared the holotype (deposited in the University of the Philippines Los Baños Museum of Natural History [UPLB-MNH]) with these specimens, and no major difference were observed.
This species was only found in the Penghu Islands but not in the main island of Taiwan. Of the two Penghu Island investigations, this species was found on low-growing plants only in the 1989 survey, possibly owing to environmental changes in the past 30 years.
Vichitbandha & Chandrapatya (2009) evaluated the biological control potential of using this species against Polyphagotarsonemus latus (Banks), a major pest that affects cultivated (crop) plants worldwide.
FIGURE. 26–29.
Amblyseius cinctus Corpuz & Rimanos, 1966, female. 26. Dorsal shield; 27. Ventral idiosoma; 28. Chelicera; 29. Spermatheca.
FIGURE. 30–33.
Amblyseius cinctus Corpuz & Rimanos, 1966, female, legs (trochanter–basitarsus). 30. Leg I; 31. Leg II; 32. Leg III; 33. Leg IV.
FIGURE. 34–36.
Amblyseius cinctus Corpuz & Rimanos, 1966, male. 34. Dorsal shield; 35. Ventral idiosoma; 36. Chelicera and spermatodactyl.
Amblyseius fletcheri Schicha, 1981
Amblyseius fletcheri Schicha, 1981: 102.
(Figures 41–48)
Female (n=2)
A lightly sclerotized mite. Idiosomal setal pattern: 10A:9B/JV-3:ZV.
Dorsal idiosoma (Figure 41). Dorsal shield, smooth, 358 (339–376) long, 219 (211–227) wide at level of s4, 222 (221–223) wide at level of S4; seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9), fourteen pairs of poroids (id1, id1a, id2, id4, idm2, idm3, idm4, idm5, idm6, idx, is1, idl2, idl3, idl4); length of dorsal setae: j1 37 (33–40), j3 52 (50–54), j4 7 (6–8), j5 6 (4–7), j6 7 (7–7), J2 8 (7–9), J5 8 (7–10), z2 8 (8–9), z4 7 (7–8), z5 9 (7–10), Z1 10 (9–11), Z4 128 (128–128), Z5 283 (260–307), s4 119 (108–130), S2 10 (10–11), S4 10 (8–11), S5 9 (9–9), r3 12 (11–14), R1 11 (11–11). Setae j1, j3, s4 longer and smooth; Z4, Z5 greatly elongated, slightly serrated; other minute. Peritreme extending beyond to j1, peritremal shield smooth, lightly sclerotized, with one pair of gland pores (gd3) and one pair of poroids (id3).
Ventral idiosoma (Figure 42). Sternal shield lateral slightly reticulated, posterior margin straight, wider than long, 67 (63–70) long, 94 (93–94) wide at st3 level, with three pairs of setae st1 34 (32–37), st2 22 (19–25), st3 27 (21–32) and two pairs of poroids (iv1, iv2). Exopodal shield at coxae II–IV. Metasternal platelets tear-shaped, with a pair metasternal setae, st4 24 (22–25), and one pair of poroids (iv3). Genital shield smooth, with one pair of genital setae st5 29 (28–30), 78 (77–80) wide at level of genital setae. Distance between st1-st1 62 (58–67), st2-st2 66 (64–68), st3-st3 70 (70–70), st1-st3 61 (61–61), st5-st5 70 (65–75). Ventrianal shield smooth, pentagonal with waist at JV2 level; 111 (109–113) long, 62 (61–62) wide at level of ZV2 and 72 (70–74) wide at level of anus; with three pairs of pre-anal setae, JV1 16 (13–20), JV2 19 (18–21), ZV2 15 (14–15), gland pore gv3 crescentic, Pa 17 (15–18), Pst 19 (18–20). Setae JV4 12 (12–12), JV5 76 (69–83), ZV1 12 (9–15), ZV3 11 (9–12) on interscutal membrane. All ventral setae smooth. Two pairs of metapodal plates: primary platelet 23 (22–24) long, 7 (6–7) wide; secondary platelet 14 (12–16) long, 2 (1–2) wide.
Chelicera (Figure 43). Movable digit 30 (29–32) long, with three teeth; fixed digit 36 (34–39) long, with eleven teeth, with pilus dentilis.
Spermatheca (Figure 44). Calyx elongated, tubular, wider toward vehicle, 36 (34–39) long, 4 (4–4) wide; atrium incorporate with calyx, minor and major ducts visible.
Legs (Figures 45–48). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): leg I, 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/ 1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge I (pd2) 48 (43–52), Sge II (pd2) 35 (34–36), Sge III (ad2) 56 (47–65), Sti III (ad) 43 (39–47), St III (d) 29 (28–30), Sge IV (ad2) 125 (120–130), Sti IV (ad) 98 (98–98), St IV (d) 74 (67–82). Macrosetae setiform.
Specimens examined
One female (no. 2522–1) from #20 (NTU); one female (no. 2540–4) from #29 (NTU).
Distribution
Africa: Madagascar (Schicha 1987). Asia: Philippines (Schicha & Corpuz-Raros 1992), Taiwan [Penghu Islands (present study)]. Oceania: Australia (Schicha 1987), New Caledonia (Schicha 1981).
Remarks
Schicha (1981) described the species based on the material collected from Musa paradisiaca in New Caledonia. We compared the specimens (deposited in UPLB-MNH) with these specimens, and no major differences were identified.
FIGURE. 37–40.
Amblyseius cinctus Corpuz & Rimanos, 1966, male, legs (trochanter–basitarsus). 37. Leg I; 38. Leg II; 39. Leg III; 40. Leg IV.
FIGURE. 41–44.
Amblyseius fletcheri Schicha, 1981, female. 41. Dorsal shield; 42. Ventral idiosoma; 43. Chelicera; 44. Spermatheca.
FIGURE. 45–48.
Amblyseius fletcheri Schicha, 1981, female, legs (trochanter–basitarsus). 45. Leg I; 46. Leg II; 47. Leg III; 48. Leg IV.
Phytoseius rachelae Swirski & Shechter, 1961
Phytoseius (Dubininellus) rachelae Swirski & Shechter, 1961: 108
Phytoseius (Phytoseius) rachelae.—Ehara 1966: 26.
(Figures 49–63)
Female (n=5)
A lightly sclerotized mite. Idiosomal setal pattern: 12A:3A/JV-3,4:ZV.
Dorsal idiosoma (Figure 49). Dorsal shield smooth, longer than wide, 298 (284–313) long, 147 (132–168) wide at level of s4, 133 (119–140) wide at level of S4, seta r3 inserted on dorsal shield; seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9), fourteen pairs of poroids (id1, id1a, id2, id4, id6, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of dorsal setae: j1 30 (27–32), j3 30 (27–32), j4 8 (6–10), j5 7 (6–8), j6 6 (5–7), J5 8 (6–11), z2 8 (6–10), z3 18 (16–21), z4 9 (7–14), z5 7 (6–9), Z4 64 (59–67), Z5 75 (65–80), s4 92 (87–97), s6 63 (56–71), r3 41 (35–44). Setae j1, j3, z3, Z4, Z5, s4, s6, r3 longer, thickened and serrated, other short and smooth. Setae r3 inserted on dorsal shield. Peritreme extending to j1 level, peritremal shield smooth, lightly sclerotized, with one pair of gland pores (gd3) and one pair of poroids (id3).
Ventral idiosoma (Figure 50). Sternal shield smooth, much wider than long, posterior margin straight, 67 (63–71) long, 88 (84–91) wide at st3 level, with three pairs of setae st1 29 (25–34), st2 26 (19–33), st3 24 (19–27) and two pairs of poroids (iv1, iv2). Exopodal shield at coxae II–IV. Metasternal platelets tear-shaped, with a pair metasternal setae, st4 24 (16–27), and one pair of poroids (iv3). Genital shield smooth, posteriorly truncate, st5 25 (22–27), 80 (77–85) wide. Distances between st1-st1 56 (55–58), st2-st2 65 (62–69), st3-st3 74 (70–78), st1-st3 59 (54–62), st5-st5 71 (68–73). Ventrianal shield smooth, much longer than wide, with waist, 92 (84–101) long, 55 (50–64) wide at level of ZV2 and 55 (50–67) wide at level of anus; with three pairs of pre-anal setae, JV1 17 (16–20), JV2 15 (13–17), ZV2 13 (10–16); gland pore gv3 small, round, migrate to the margin of ventrianal shield, Pa 14 (13–15), Pst 14 (12–16) one shield. Setae JV5 48 (41–51), ZV1 19 (17–20), ZV3 13 (10–17) on interscutal membrane. All ventral setae smooth, except seta JV5 thickened and serrated. One pair of metapodal plates: primary platelet 24 (18–29) long, 4 (3–4) wide.
Chelicera (Figure 51). Movable digit 24 (23–27) long, with one tooth; fixed digit 25 (23–28) long, with three teeth, with pilus dentilis.
Spermatheca (Figure 52). Calyx of spermatheca goblet-shaped, flaring distally, 9 (8–11) long, 5 (5–6) wide, and atrium nodular, major and minor ducts visible.
Legs (Figures 53–56). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 2-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge IV (ad2) 21 (19–24), Sti IV (ad) 49 (48–50), Sbta IV (d) 30 (27–33), Sdta IV (d) 23 (21–25). Macrosetae apically shovel-shaped with expanded blade.
Male (n=5)
A lightly sclerotized mite. Idiosomal setal pattern: 12A:3A/JV-3,4:ZV-1,3.
Dorsal idiosoma (Figure 57). Dorsal shield smooth, longer than wide, 233 (225–245) long, 142 (130–157) wide at level of s4, 119 (107–135) wide at level of S4; seven pairs of gland pores (gd1, gd2, gd4, gd5, gd6, gd8, gd9), fourteen pairs of poroids (id1, id1a, id2, id4, id6, idm2, idm3, idm4, idm5, idm6, is1, idl2, idl3, idl4); length of setae: j1 21 (17–23), j3 26 (25–26), j4 6 (5–8), j5 6 (4–7), j6 5 (4–6), J5 6 (5–7), z2 7 (7–8), z3 11 (8–14), z4 8 (7–9), z5 6 (4–9), Z4 39 (36–43), Z5 44 (40–48), s4 60 (52–66), s6 41 (38–43), r3 33 (28–37), Setae j1, j3, z3, Z4, Z5, s4, s6, r3 longer, thickened and serrated, other short and smooth. Setae r3 inserted on dorsal shield. Peritreme extending to j3 level; peritremal shield lightly sclerotized.
Ventral idiosoma (Figure 58). Sternogenital shield smooth, posterior margin almost straight, much longer than wide, 119 (117–121) long, 84 (82–89) wide at level st2, with five pairs of setae st1 25 (22–27), st2 22 (16–26), st3 21 (19–22), st4 19 (18–18), st5 17 (14–20), three pairs of poroids (iv1, iv2, iv3). Exopodal shield at coxae II–IV. Distance between st1-st1 52 (52–54), st2-st2 57 (54–61), st3-st3 66 (64–68), st4-st4 56 (55–57), st5-st5 49 (43–51), st1-st5 103 (99–106). Ventrianal shield subtriangular, reticulated, 95 (91–100) long, 145 (136–151) wide at level of anterior corner and 75 (70–79) wide at level of anus, not fused with peritremal shield cingulum; with three pairs of pre-anal setae, JV1 14 (11–16), JV2 12 (10–14), ZV2 11 (11–12); gland pore gv3 small, round, migrate from the normal position, Pa 12 (11–13), Pst 12 (10–12) on shield; JV5 20 (17–22) on interscutal membrane. All ventral setae smooth.
Chelicera (Figure 59). Movable digit 17 (16–21) long, with one tooth; fixed digit 17 (16–20), with four teeth, with pilus dentilis; spermatodactyl L-shaped, shaft 15 (13–16) long, heel rounded, foot 9 (8–9) long.
Legs (Figures 60–63). Complement of setae on coxae I–IV: 2-2-2-1. Complement of setae on trochanter I–IV: 5-5-5-5. Chaetotaxy (femur to basitarsus): 2-3/1-2/2-2, 2-2/1-2/1-2, 2-2/1-2/1-2, 1-1/1-1; leg II, 2-3/1-2/1-1, 2-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg III, 1-2/1-1/0-1, 1-2/0-2/0-1, 1-1/1-2/1-1, 1-1/1-1; leg IV, 1-2/1-1/0-1, 1-2/1-2/0-1, 1-1/1-2/0-1, 1-1/1-1. Macrosetae: Sge IV (ad2) 15 (13–18), Sti IV (ad) 25 (21–30), Sbta IV (d) 28 (26–29). Sdta IV (d) 21 (19–23). Macrosetae apically shovel-shaped with expanded blade.
Specimens examined
Three females one male (89-Ph-0270, 71, 72, 80) from #1 (TARL); 11 females 5 males (89-Ph-0241, 42, 44, 51, 52, 54, 55, 56, 57, 62, 63, 74, 75, 77, 89, 90) from #4 (TARL); two females (89-Ph-0273- 76) from #5 (TARL); two females (89-Ph-0268, 86) from #9(TARL); four females two males (89-Ph-0240, 43, 53, 58, 59, 88) from #11 (TARL); seven females four males (89-Ph-0245, 46, 65, 66, 67, 81, 82, 83, 84, 85, 87) from #14 (TARL); one female (89-Ph-0264) from #17 (TARL).
Distribution
Asia: China [Hong Kong (Swirski & Shechter 1961)], India (Gupta 1980), Indonesia (Ehara 2002), Taiwan [Penghu Islands (present study)].
Remarks
Swirski & Shechter (1961) described the species, having found it on the lower side of leaves of Rhus chinensis (Anacardiaceae) in Hong Kong. After that, this species was reported in India (Gupta 1980) and Indonesia (Ehara 2002). Based on our phytoseiid survey, this species was only found in the Penghu Islands; no specimens were found in the main island of Taiwan. Additionally, this species was only found in the 1989 survey.
The holotype of the species was collected from the lower side of leaves of R. chinensis (Anacardiaceae), and paratypes and additional specimens were collected from plants with pubescent leaves. Therefore, the species is considered to have a subtype III-a lifestyle which is characterized as a generalist predator that lives on pubescent leaves (McMurtry et al. 2013).
FIGURE. 49–52.
Phytoseius rachelae Swirski & Shechter, 1961, female. 49. Dorsal shield; 50. Ventral idiosoma; 51. Chelicera; 52. Spermatheca.
FIGURE. 53–56.
Phytoseius rachelae Swirski & Shechter, 1961, female, legs (trochanter–basitarsus). 53. Leg I; 54. Leg II; 55. Leg III; 56. Leg IV.
FIGURE. 57–59.
Phytoseius rachelae Swirski & Shechter, 1961, male. 57. Dorsal shield; 58. Ventral idiosoma; 59. Chelicera and spermatodactyl.
FIGURE. 60–63.
Phytoseius rachelae Swirski & Shechter, 1961, male, legs (trochanter–basitarsus). 60. Leg I; 61. Leg II; 62. Leg III; 63. Leg IV.
Discussion
The Phytoseiidae fauna in the Penghu Islands is studied for the first time in this study. Herein, we reported the results of two phytoseiid surveys conducted in the Penghu Islands in 1989 and 2020. We documented 16 phytoseiid species, including two new species belonging to the Proprioseiopsis and Neoseiulus genera, and three species not recorded in the main island of Taiwan (Liao et al. 2020). The Phytoseiidae species in the Penghu Islands are similar to the species found in the main island of Taiwan, Southern China, Okinawa, and the Philippines. The lists of phytoseiid species recorded from the investigations in 1989 and 2020, however, are quite different. Several possible reasons that may be changed over time such as climate, habitat, plant species, invasive plant influences, human activities and socioeconomic structures etc. (Hsu 2005; Wei et al. 2020). The comprehensive phytoseiid investigation in Penghu Islands is needed in the future to explore what factors affected the phytoseiid mite fauna.
In addition, the land of the Penghu Islands has high salinity owing to its proximity to the sea, coastal plants dominate these islands. Hibiscus tiliaceus is the most dominant plant on which we observed many phytoseiid individuals with a subtype III-a lifestyle. Also, Liao et al. (2017) described T. (A.) crossostephium from rocky shores on Lanyu Island, a special habitat for phytoseiid mites based on the lifestyle classification proposed by McMurtry et al. (2013). We assumed that the species would also be present in the Penghu Islands where rocky shores are also quite common. However, we did not find any in the present study. Many islands of the Penghu archipelago have a potential for description of new species and new records are waiting for further expedition.
Acknowledgements
We thank to İ. Döker (CU, Turkey), S.F. Lin (NCHU, Taiwan) and Y. Hsiao (CSIRO & ANU, Australia) for their valuable suggestions. We also thank M. Ohara and H. Kajihara (HUM, Japan), L. A. Corpuz-Raros, and J. Naredo (UPLB-MNH, Philippines) for lending type specimens for comparison. Thanks to Y. H. Lin and Julia Chang (NTU, Taiwan) for field collection of the Penghu Islands. Thanks to S. F. Shiao (NTU, Taiwan) for providing great help after CCK passed away. Thanks to Wallace Academic Editing for English editing of the draft. This study was supported by grants MOST105-2621-B-002-002-MY3 and MOST108-2621-B-002-005-MY3 from the Ministry of Science and Technology, Taiwan.
