Gracilentulus fjellbergi Szeptycki 1993
Creators: name: Bu, Yun
name: Yin, Wen Ying
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Entognatha
Protura
Acerentomidae
Gracilentulus
Gracilentulus fjellbergi

description: Gracilentulus fjellbergi Szeptycki, 1993, new record to Chinese fauna
(Figs. 12 – 26)
Description (Chinese specimens). Adult. Body length 1108 – 1173 µm (n=10).
Head— Oval, length 100 – 118 µm, width 78 – 93 µm (n=10). Postpseudocular seta present, additional seta absent. Seta ls short. Rostrum not protruded (Fig. 12). Pseudoculus almost circular, length 7.5µm, width 7.5 – 10 µm. PR=13.3 – 15.7 (Figs. 13). Maxillary gland small, with short canal and smooth calyx, and with blind end obviously split into two leaves. Hind part of maxillary gland length 15 – 17.5 µm. CF=6.4 – 7 (Figs. 14). Maxillary palpus with two filiform sensilla, subequal (Fig. 15). Labial palpus reduced, with three setae and one short parallel-sided sensillum (Fig. 16)
Thorax— Chaeotaxy as shown in Table 2. Seta 1 on pronotum extremely long, about 2.5 times the length of seta 2 (Fig. 17). Thoracic tergites II – III with two anterior setae (A2 and A4), setae A4, P2 and P3 extremely long, seta P5a reduced (Fig. 17). Pronotum with no pores, mesonotum and metanotum with pore l. Thoracic sterna with no pores.
Foretarsal length 88 – 95 µm, claw length 20 – 25 µm, TR =3.6 – 4.5; Empodium short, EU=0.15 – 0.17; Sshaped seta length 25 – 28 µm. Dorsal sensillum t-1 claviform, BS=0.37 – 0.41; t-2 long and thin and curved; t- 3 gemmiform. Exterior sensillum a filiform, reaching base of γ 3; b very close to c, c obviously longer than b, reaching base of f; d situated half way between c and e; e extremely long, slightly surpassing base of claw; f and g filiform; g relatively short. Interior sensillum a' robust, slightly lower than level of t-1; b' slim, filiform; c' thin and long, its apex surpassing base of claw. Length formula of foretarsal sensilla as: t-3 <t-1 <g = b' <c' <d = a' = t-2 <f <a <b = e <c (Figs. 18 – 19). Middle tarsal length 40 – 43 µm, claw length 15 – 18 µm, hind tarsal length 48 µm, both claw 18 – 20 µm in length.
Abdomen —Chaeotaxy as shown in Table 2. Abdominal tergite I with three pairs of anterior setae (A1, A2 and A5), posterior seta P1a absent. Urotergites II – VI with four pairs of anterior setae (A1, A2, A4 and A5), without posterior setae P1a and P3a. Urotergite VII with medial anterior setae Ac, posterior seta P1a present. Urotergite I with pore psm, other pores absent. Urotergites II – VII with pores al and psm, with no pores psl and l.
Abdominal legs II and III with subapical seta about three times the length of apical one (Fig. 20). Urosternites I – IV without pores. Urosternites V – VII with one pair of symmetrical pores. Two membranal pores present on the membrane between laterotergite and sternite of abdominal segments V – VI (Fig. 21).Pore on laterotergite VII situated anterior to A5 (Fig. 22).
Striate band on abdominal segment VIII well developed. Segment VIII with paired pores psm on urotergite and without pores on urosternite. Comb oblique rectangle, with 10 teeth on hind margin (Fig. 25).
Segments IX – XI without pores on urotergites and urosternites. Urosternite XI with 3 + 3 setae, seta 2 very short, setae 1 and 3 long. Segment XII with single middle pore on the tergite, with paired pores al on sternite (Figs. 23 – 24).
Female squama genitalis with pointed acrostyli (Fig. 26). Male unknown.
Younger instars
Maturus junior— Body length 1025 – 1060 µm (n=4). Head length 95 – 100 µm, width 78 – 80 µm (n=4). Pseudoculus length 6.3 – 7.5 µm, width 5 – 7.5 µm, PR=12.7 – 13.3. Hind part of maxillary gland length 15 µm. CF=6.3 – 6.7. Fortarsal length 73 – 80 µm; claw length 18 – 20 µm; TR =3.6 – 4.3, EU=0.13 – 0.14; S-shaped seta length 18 µm; BS=0.36 – 0.41; Middle tarsal length 35 – 38 µm, claw length 13 – 15 µm. Hind tarsal length 40 – 43 µm, claw length 13 – 15 µm. Compared with imago, urotergites II – VII lack A4, urotergite IX lack seta 4a, urotergite X lack setae 1a and 2a, urosternite XI lack setae 1 and 3. Comb on abdominal VIII with seven teeth.
Other younger instars —unknown.
Chaetal variability —Imagoes (18 specimens). Urosternite I asymmetrical with P2 on the right (W0602).Urotergite I asymmetrical lack P2 on the right (W0630). Urotergite VII asymmetrical lack A2 on the right (W0653), presence of A1 + A1 instead of Ac (W0654). Urotergite VIII with Mc instead of M1 + M1 (W0630, W0631, W0633, W0653, W0654, W0657, W0661).
Maturus juniors (4 specimens). Urotergite VII asymmetrical with A2 on the right (W0650). Urosternite VII asymmetrical lack P2 on the left (W0650-W0652).
Specimens examined. 18 females (No: W0602, W0630-W0633, W0653-W0665), 4 maturus juniors(No: W0649-W0652), mounted, from latifoliate forest of Mt. Hongshan, 43 o 48' N, 87 o 36' E, 910 m alt., Urumchi, Xinjiang Province, China, 21-V-2006, collected by Dr. Yun-Xia Luan, Yan Gao and Yun Bu.
Distribution. Urumchi, Xinjiang Province, Northwest China; Portual; Spain (Canary Island); Poland; Azerbaijan.
description: Published as part of Bu, Yun & Yin, Wen Ying, 2007, The Protura from Xinjiang, Northwestern China, pp. 29-46 in Zootaxa 1437 on pages 33-35, DOI: 10.5281/zenodo.175891