Eosentomon xinjiangense, Bu, Yun & Yin, Wen Ying, 2007

Bu, Yun & Yin, Wen Ying, 2007, The Protura from Xinjiang, Northwestern China, Zootaxa 1437, pp. 29-46 : 40-43

Eosentomon xinjiangense new species

( Figs. 24 – 29 )

Diagnosis. Sensillum b'-1 on foretarsus present; metanotum with 10 pairs of posterior setae, with very short setae P5a and P5a', P5a adhere to P5; urotergites V – VII lack seta A3, with four pairs of anterior setae; urosternites VIII – XI with chaetotaxy 2/7, 6, 6, 8; seta D2 of leg III in normal shape.

Description. Adult. Body length 1165 – 1433 µm (n=8).

Head— elliptic, length 95 – 105 µm, width 93 – 100 µm (n=8). Head setae short, subposterior seta 1.3 – 1.5 x length of posterior seta. Anterior additional seta, m4 and posterior additional present ( Fig. 39 ). Pseudoculus circular, width 7.5 – 10 µm, with three lines, the middle line longer than lateral ones ( Fig. 40 ). PR=11 – 14. Clypeal apodeme indistinct. Rostral seta simple, subequal to subrostral( Fig. 41 ). Labral seta present. Mandibles with three small distinct apical teeth ( Fig. 42 ). Digits of galea well-developed, median and inner equal, shorter and thicker than outer ( Fig. 43 ). Maxillary palpus with two sensilla, dorsal sensillum obviously longer than lateral one ( Fig. 44 ).

Thorax— Chaetotaxy as shown in Table 5 . Tracheal camerae long and slender. Spiracle diameter 4 – 5 µm ( Fig. 46 ). Three little setae present on the lateral pleuron between pronotum and mesonotum. On mesonotum and metanotum, P1a situated posterior to the row of P1 and P2, length ratio of P1: P1a: P2 on mesonotum as 1.7 – 2: 1: 2 – 2.2(in larvae II 1.3 – 1.5: 1: 1.7 – 2). P2a short than P3a, P3a setiform. Metanotum with very short setae P5a and P5a', P5a adhere to P5 ( Fig. 45 ). Sternites of thorax with no pores.

Foretarsal length 83 – 85 µm, claw length 10 – 13 µm, TR =7.3 – 8.5; Empodium shorter than claw, EU=0.7 – 0.8; S – shaped seta short. Dorsal sensillum t-1 short claviform, situated at half distance α 3 – α 3', BS=0.93 – 1; t- 2 and t-3 short. Exterior sensillum a, b, and c short, subequal; d robust, broad at the basal; e and g spatulate; f- 1 filiform; f-2 short. Interior sensillum a' relatively robust, not reaching level of α 4; b'-1 and b'-2 short, filiform; c' very short ( Figs. 47 – 48 ). Middle tarsal length 33 – 35 µm, claw length 9 – 10 µm. Hind tarsal length 38 – 42 µm, claw length 10 – 13 µm. Empodial appendage of II and III legs long; basal seta (seta D2) of III leg of normal shape ( Fig. 49 ).

Abdomen —Chaetotaxy as shown in Table 5 . Urotergite I with two pairs of anterior setae (A1, A2), with six pairs of posterior setae (P1, P1a, P2, P3, P3a, P4a), P3a and P4a modified as short sensillum-like ( Fig. 50 ). Seta A3 on urotergites V – VII absent. Seta P1a on urotergites I – VI long, longer than P1; on urotergite VII situated posteriorly to the level of P1 – P2, short; P2a on Urotergites II – IV as P1a, on VII slightly shorter. P1 a' on urotergite VIII short and thin ( Fig. 51 – 53 ). Urosternite VIII with one pair of anterior setae and seven posterior setae; sternites IX – X with three pairs of setae (1, 1a, 2). Lateral sclerotization on sternite distinct. Urotergites I – V with no pores, VI – X with one pair of pores, situated posteriorly. Urosternites I – III with no pores, IV – X with one medial pore. Segment XII with two anterior medial pores on tergite and one medial pore on sternite.

On female squama genitalis, caput processus big and curved towards the median edge of stylus, filum processus slim and long ( Fig. 54 ). Penis with short setae.

Younger instars

Larva II —Body length 885 – 1133 µm. Head length 90 – 100 µm, width 85 – 95 µm. Pseudoculus width 7.5 µm, PR=11 – 14. Fortarsal length 65 – 75 µm; claw length 7.5 – 10 µm; TR =6.8 – 7.5; Empodium short, EU=0.83 – 0.9; BS=0.93 – 1; Middle tarsal length 28 – 33 µm, claw length 7.5 µm. Hind tarsal length 33 – 37 µm, claw length 7.5 – 10 µm. Spiracle diameter 2.5 – 3 µm.

Other younger instars —unknown.

Holotype —female (No: W0615) (mounted), from coniferous forest of Mt. Nanshan, 43 o 25' 338 N, 87 o 09' 875 E, 2100 m alt., Urumchi, Xinjiang Province, China, 21 – V-2006, collected by Dr. Yun-Xia Luan, Yan Gao and Yun Bu.

Paratype — 4 females (No: W0618, W0640, W0671, W0672) (mounted), 6 males (No: W0611, W0616, W0666-W0669), same data as for holotype.

Other specimens examined— 3 males, 5 Larvae II, same data as for holotype.

Etymology. The species was named after Xinjiang Province where the type specimens were collected.

Distribution. Xinjiang Province, Northwest China.

Remarks. Eosentomon xinjiangense sp. n. is similar to E. dissimilis Yin, 1979 , E. linearis Yin, 1979 and E. konsenense Imadat, 1994 . It can be distinguished from E. dissimilis by the caput of female squama genitalis, chaetotaxy of metanotum and urotergite I, from E. linearis by the position of seta P1a' on urotergite VIII and the presence of sensillum b'-1 on foretarsus, from E. konsenense by the shape of caput of female squama genitalis and the structure of pseudoculus.

Figures

FIGURES 21 – 26. Gracilentulus fjellbergi Szeptycki, 1993. 21, urosternite V (arrows – pores). 22, urosternite VII (arrows – pores). 23, urotergites VIII – XII. 24, urosternites VIII – XII. 25, comb on abdominal VIII. 26, female squama genitalis.

FIGURES 27 – 38. Nanshanentulus urumchiensis sp. n. 27, head, dorsal view. 28, pseudoculus 29, canal of maxillary gland. 30, maxillary palpus. 31, labium. 32, foretarsus, exterior view. 33, foretarsus, interior view. 34, urotergites VIII – XII. 35, urosternites VIII – XII. 36, comb on abdominal VIII. 37, female squama genitalis. 38, penis.

FIGURES 39 – 54. Eosentomon xinjiangense sp. n. 39, head. 40, pseudoculus. 41, rostral (r) and subrostral (sr) setae. 42, mandible. 43, galea. 44, maxillary palpus. 45, parts of pronotum, mesonotum and metanotum. 46, spiracle. 47, foretarsus, exterior view. 48, foretarsus, interior view. 49, leg III. 50, hind part of urotergite I. 51, hind part of urotergite VI. 52, hind part of urotergite VII. 53, hind part of urotergite VIII. 54, female squama genitalis.

Tables

TABLE 5. Chaetotaxy of Eosentomon xinjiangense sp. n.

	Larva II		Imago
	Formula	Composition of Setae	Formula	Composition of Setae
Dorsal
Thorax I	4	1,2	4	1,2
II	6 ------ 16	A1,2,M P1,1a,2,2a,3,4,5,5a	6 ------ 16	A1,2,M P1,1a,2,2a,3,3a,4,5
III	6 ------ 18	A1,2,M P1,1a,2,2a,3,4,5,5a,5a'	6 ------ 20	A1,2,M P1,1a,2,2a,3,3a,4,5,5a,5a'
Abdomen I	0 ------ 10	P1,1a,2,3,3a	4 ------ 12	A1,2 P1,1a,2,3,3a,4a
II	2 ------ 14	A5 P1,1a,2,2a,3,4,4a	10 ------ 16	A1,2,3,4,5 P1,1a,2,2a,3,4,4a,5
III	4 ------ 14	A4,5 P1,1a,2,2a,3,4,4a	10 ------ 16	A1,2,3,4,5 P1,1a,2,2a,3,4,4a,5
IV	4 ------ 16	A4,5 P1,1a,2,2a,3,4,4a,5	10 ------ 16	A1,2,3,4,5 P1,1a,2,2a,3,4,4a,5
V – VII	4 ------ 16	A4,5 P1,1a,2,2a,3,4,4a,5	8 ------ 16	A1,2,4,5 P1,1a,2,2a,3,4,4a,5
VIII	6 --- 9	M2,3,4 Pc,1,2,3,4	6 --- 9	M2,3,4 Pc,1,2,3,4
IX	8	1,2,3,4	8	1,2,3,4
X			8	1,2,3,4
XI			8	1,2,3,4
XII	9		9
Ventral
Thorax I	6 – 2 ------------ 6	A1,2,3,M P1,2,3	6 – 2 ------------ 6	A1,2,3,M P1,2,3
II	6 – 2 ------------ 6	A1,2,3,M P1,2,3	6 – 2 ------------ 6	A1,2,3,M P1,2,3
III	6 – 2 ------------ 6	A1,2,3,M1 P1,2,3	6 – 4 ------------ 6	A1,2,3,M1,2 P1,2,3
Abdomen I	4 --- 4	A1,2 P1,2	4 --- 4	A1,2 P1,2
II	4 --- 4	A1,2 P1,2	6 --- 4	A1,2,3 P1,2
III	4 --- 4	A1,2 P1,2	6 --- 4	A1,2,3 P1,2
IV – VI	4 --- 8	A1,2 P1,2,2a,3	6 ------ 10	A1,2,3 P1,2,2a,2a',3
VII	4 --- 8	A1,2 P1,2,2a,3	6 ------ 10	A1,2,3 P1,2,2a,2a',3
VIII	0 --- 7	Pc,1,1a,2	2 --- 7	A Pc,1,1a,2
IX	4	1,2	6	1,1a,2
X			6	1,1a,2
XI			8	1,2,3,4
XII	12		12