Corresponding author: Yun Bu (
Academic editor: Bruce A. Snyder
Jin Y-L, Bu Y (2023) Two new species of the genus
Symphylans are minute soil arthropods present in various habitats, and some species are important crop pests (
Specimens were obtained by extraction of soil and litter samples from broad-leaf and bamboo forests using Berlese-Tullgren funnels. Specimens were preserved in 80% ethanol. They were mounted on slides using Hoyer’s solution and dried in an oven at 50 °C. Observations were performed under a phase contrast microscope (Leica DM 2500). Photographs were taken with a digital camera (Leica DMC 4500) mounted on the microscope. Line drawings were made using a drawing tube. All specimens are deposited in the collections of Shanghai Natural History Museum (
Adult body 2.1 mm long in average (1.9–2.2 mm,
Numbers of setae and sensory organs on antennae of
Antennomere | Primary whorl setae | Secondary whorl setae | Rudimentary spined sensory organs | Cavity-shaped organs on dorsal side | Bladder-shaped organs |
---|---|---|---|---|---|
1 | 6 | 1 | |||
2 | 8 | 1 | |||
3 | 8 | 1 | |||
4 | 9 | 1 | |||
5 | 9 | 1 | |||
6 | 11 | 1 | 1 | ||
7 | 11 | 2 | 1 | 1 | |
8 | 11 | 2 | 0 | 1 | |
9 | 10 | 3 | 0 | 1 | |
10 | 11 | 3 | 1 | 1 | 1 |
11 | 11 | 4 | 1 | 1 | 1 |
12 | 11 | 5 | 1 | 1 | 1 |
13 | 11 | 6 | 1 | 1 | 2 |
14 | 11 | 6 | 0 | 1 | 3 |
15 | 10 | 7 | 0 | 1 | 3 |
16 | 10 | 6 | 3 | 5 | |
17 | 10 | 6 | 3 | 8 |
Chaetotaxy of tergites of
Tergite | Lateromarginal setae | Inserted setae | Central setae | Other setae |
---|---|---|---|---|
1 | 4+4 | |||
2 | 6–7 (6) | 1–2 (2) | 1–2 (2) | 6–10 (6) |
3 | 8–10 (8) | 1–2 (2) | 1–3 (2) | 14–25 (14) |
4 | 5–7 (6) | 1–2 (1) | 3–5 (3) | 10–15 (11) |
5 | 5–7 (6) | 1–2 (2) | 2–4 (3) | 7–13 (12) |
6 | 8–10 (9) | 1–2 (2) | 2–4 (4) | 17–28 (20) |
7 | 5–7 (6) | 1–2 (2) | 4–6 (4) | 10–14 (11) |
8 | 5–7 (6) | 1–3 (2) | 3–5 (4) | 10–14 (10) |
9 | 8–10 (9) | 1–3 (1) | 3–5 (3) | 20–27 (22) |
10 | 5–6 (6) | 1–2 (1) | 4–6 (4) | 9–14 (11) |
11 | 5–8 (6) | 1–2 (1) | 3–5 (4) | 7–14 (9) |
12 | 7–10 (8) | 1–2 (2) | 3–5 (3) | 15–24 (15) |
13 | 4–7 (5) | 0–2 (1) | 2–5 (3) | 8–14 (8) |
14 | 17–26 (21) | |||
15 | 6–9 (7) | 0/2 (0) | 2–4 (3) | 14–19 (14) |
16 | 12–17 (14) | |||
17 | 27–38 (29) |
Measurements of tergites and processes of
Tergite | Length | Width | Length of processes | Basal width of processes | Basal distance between processes |
---|---|---|---|---|---|
1 | 24 ± 7 (23) | 141 ± 13 (138) | |||
2 | 48 ± 5 (45) | 144 ± 7 (150) | 37 ± 3 (33) | 41 ± 3 (43) | 28 ± 4 (32) |
3 | 102 ± 14 (100) | 186 ± 25 (180) | 41 ± 4 (42) | 45 ± 3 (47) | 33 ± 3 (37) |
4 | 57 ±7 (55) | 194 ± 17 (205) | 33 ± 3 (35) | 49 ± 5 (52) | 60 ± 8 (65) |
5 | 71 ± 12 (65) | 183 ± 10 (190) | 41± 5 (45) | 43 ± 4 (45) | 62 ± 7 (67) |
6 | 121 ± 9 (125) | 223 ± 38 (235) | 47± 5 (47) | 48 ± 4 (47) | 62 ± 6 (67) |
7 | 70 ± 9 (65) | 229 ± 18 (242) | 36 ± 5 (40) | 48 ± 6 (50) | 85 ± 10 (95) |
8 | 74 ± 5 (82) | 204 ± 13 (205) | 45 ± 4 (50) | 45 ± 3 (50) | 77 ± 10 (85) |
9 | 114 ± 26 (120) | 253 ± 21 (250) | 46 ± 4 (50) | 46 ± 4 (50) | 72 ± 6 (75) |
10 | 76 ± 14 (82) | 235 ± 23 (250) | 34 ± 3 (37) | 48 ± 4 (50) | 92 ± 16 (100) |
11 | 73 ± 7 (70) | 207 ± 13 (210) | 41 ± 4 (45) | 43 ± 3 (42) | 78 ± 9 (85) |
12 | 115 ± 7 (115) | 255 ± 12 (260) | 41 ± 4 (45) | 47 ± 7 (50) | 74 ± 9 (77) |
13 | 68 ± 10 (60) | 233 ± 24 (245) | 28 ± 5 (32) | 48 ± 6 (55) | 89 ± 12 (90) |
14 | 68 ± 10 (60) | 205 ± 20 (210) | |||
15 | 93 ± 9 (90) | 226 ± 21 (247) | 28 ± 3 (32) | 45 ± 5 (52) | 67 ±8 (75) |
16 | 72 ± 6 (80) | 185 ± 25 (200) | |||
17 | 110 ± 8 (125) | 172 ± 21 (175) |
From the Greek words “macro” meaning “large” and “chaeta” meaning “seta”. The species name “
China (Shanghai, Zhejiang).
Adult body 2.4 mm long in average (1.8–2.6 mm,
Numbers of setae and sensory organs on antennae of
Antennomere | Primary whorl setae | Secondary whorl setae | Rudimentary spined sensory organs | Cavity-shaped organs on dorsal side | Bladder-shaped organs |
---|---|---|---|---|---|
1 | 6 | ||||
2 | 8 | 1 | |||
3 | 8 | 1 | |||
4 | 9 | 1 | |||
5 | 10 | 1 | |||
6 | 10 | 1 | |||
7 | 10 | 1 | 1 | ||
8 | 10 | 0 | 1 | ||
9 | 10 | 0 | 1 | ||
10 | 10 | 1 | 0 | 1 | |
11 | 10 | 1 | 1 | 1 | |
12 | 11 | 3 | 1 | 1 | 1 |
13 | 11 | 4 | 0 | 1 | 3 |
14 | 11 | 4 | 0 | 1 | 5 |
15 | 11 | 5 | 2 | 9 | |
16 | 11 | 4 | 3 | 13 | |
17 | 10 | 5 | 2 | 13 |
Chaetotaxy of tergites of
Tergite | Lateromarginal setae | Inserted seta | Central setae | Other setae |
---|---|---|---|---|
1 | 3+3 | |||
2 | 5–6 (6) | 1 (1) | 1 (1) | 5–7 (6) |
3 | 7–8 (7) | 1 (1) | 1 (1) | 16–19 (16) |
4 | 5 (5) | 1 (1) | 1–2 (2) | 8–8 (8) |
5 | 5 (5) | 1 (1) | 1–2 (1) | 7–10 (8) |
6 | 7–8 (7) | 1 (1) | 2–3 (2) | 15–20 (20) |
7 | 5 (5) | 1 (1) | 2–3 (2) | 8–10 (8) |
8 | 5 (5) | 1 (1) | 2 (2) | 0–11 (9) |
9 | 7–8 (7) | 1 (1) | 2–3 (3) | 16–20 (18) |
10 | 5 (5) | 1 (1) | 2–3 (3) | 8–10 (8) |
11 | 5–6 (5) | 1 (1) | 2–3 (2) | 6–10 (9) |
12 | 6–7 (7) | 0/1 (1) | 2–3 (3) | 15–20 (17) |
13 | 4–5 (5) | 0/1 (1) | 1–2 (2) | 7–8 (7) |
14 | 15–18 (16) | |||
15 | 4–7 (5) | 0/1 (1) | 1–2 (2) | 8–14 (14) |
16 | 10–14 (14) | |||
17 | 10–14 (14) |
Measurements of tergites and processes of
Tergite | Length | Width | Length of processes | Basal width of processes | Basal distance between processes |
---|---|---|---|---|---|
1 | 27 ± 3 (25) | 126 ± 2 (125) | |||
2 | 45 ± 6 (50) | 123 ± 10 (130) | 32 ± 2 (34) | 28 ± 2 (30) | 33 ± 3 (33) |
3 | 97 ± 16 (90) | 151 ± 8 (155) | 34 ± 2 (37) | 28 ± 2 (32) | 39 ± 2 (40) |
4 | 60 ± 8 (62) | 162 ± 9 (170) | 31 ± 2 (29) | 34 ± 1 (33) | 47 ± 6 (50) |
5 | 60 ± 12 (75) | 138 ± 5 (140) | 35 ± 4 (39) | 28 ± 3 (30) | 52 ± 5 (50) |
6 | 115 ± 12 (125) | 181 ± 17 (192) | 39 ± 3 (41) | 31 ± 4 (33) | 60 ± 4 (63) |
7 | 72 ± 12 (85) | 191 ± 10 (202) | 38 ± 4 (36) | 39 ± 6 (35) | 65 ± 7 (75) |
8 | 71 ± 12 (80) | 160 ± 9 (170) | 35 ± 3 (38) | 27 ± 3 (29) | 65 ± 5 (70) |
9 | 124 ± 10 (138) | 199 ± 6 (205) | 37 ± 3 (41) | 30 ± 3 (34) | 68 ± 7 (75) |
10 | 74 ± 12 (90) | 196 ± 17 (207) | 36 ± 3 (37) | 36 ± 6 (36) | 74 ± 5 (80) |
11 | 72 ± 9 (80) | 171 ± 5 (175) | 35 ± 1 (34) | 29 ± 3 (25) | 70 ± 6 (78) |
12 | 121 ± 18 (125) | 201 ± 14 (217) | 37 ± 4 (38) | 30 ± 6 (32) | 66 ± 7 (70) |
13 | 71 ± 6 (75) | 184 ± 16 (207) | 29 ± 3 (27) | 36 ± 12 (30) | 66 ± 9 (72) |
14 | 68 ± 10 (75) | 164 ± 8 (175) | |||
15 | 99 ± 10 (100) | 180 ± 13 (200) | 27 ± 2 (30) | 26 ± 3 (26) | 55 ± 8 (65) |
16 | 71 ± 7 (75) | 148 ± 16 (162) | |||
17 | 92 ± 9 (92) | 131 ± 9 (135) |
The species name is derived from the Latin words “
Known only from the type locality.
The mandible structure of
In our study of
Frons of
According to our observations, the frons of
Comparison of chaetotaxy on frons of
Characters |
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Number of macrosetae (M) | 10 | 8 | 6 | 8 | 8 | 4 |
Formula of M-setae | 4/4/2 | 4/2/2 | 2/2/2 | 4/2/2 | 4/2/2 | 0/2/2 |
length of M-setae (μm) | 58–73 | 21–28 | 25–37 | 22–37 | 20–30 | 12–20 |
length of a0 setae (μm) | 12–15 | 7–8 | 12 | 12–15 | 10–16 | 7–11 |
M/a0 | 4–5.6 | 2.8–3.7 | 2–3 | 1.5–2.7 | 1.6–2.7 | 1.4–2.4 |
We sincerely thank Dr Jing-Yang Li, Mrs Si-Qi Yang and Mr Cheng-Wang Huang for their generous help in the collection. We appreciate Dr Nerivania Nunes Godeiro for the linguistic corrections to the manuscript. Special thanks are given to Dr Derek Hennen (USA) and an anonymous reviewer for their valuable comments in review of the manuscript. This research was supported by the National Natural Science Foundation of China (no. 32170471) and the Research Foundation of Shanghai Science and Technology Museum.