Sinella gei, Pan, Zhi-Xiang, Zhang, Feng & Shi, Shi-Di, 2012

Pan, Zhi-Xiang, Zhang, Feng & Shi, Shi-Di, 2012, Contribution to study of eyed species of Sinella (Collembola: Entomobryidae), with a key to this group of species from China, Zootaxa 3180, pp. 35-46 : 38-41

Sinella gei n. sp.

Figs 17–29 , Table 2

Type materials. Holotype: male on slide, CHINA: Qinhai Province, Xining City, National Food station, 1. viii. 2009, collected by C. Ge (sample number C9588), deposited in NJU. Paratypes: 1 male and 1 female, same data as holotype. Male paratype deposited in TZU, holotype and other paratypes in NJU.

Description. Body length up to 2.7 mm, pale yellow to white.

Antenna about 1.2 times as long as cephalic diagonal. Antennal segments ratio as I:II:III:IV = 1:2.0–2.2:1.5– 1.8:3.6–3.7. Basal Ant. I with 3 dorsal and 4 ventral smooth spiny mic. Basal Ant. II with 5 smooth spiny mic. Distal Ant. II with 2–3 dorsal rod-like setae.

Eyes 5+5. Labral papillae absent. Prelabral and labral setae 4/554, all smooth; labial intrusion U-shaped Lateral process of labial palp slightly curved, thicker than normal setae, with tip beyond apex of labial papilla ( Fig. 17 ). Subapical seta of maxillary outer lobe slightly thicker than apical one; 3 smooth sublobal hairs on maxillary outer lobe. Labial setae as MREL1L2; R ciliate and others smooth; seta R about 0.5 length of seta M; setae X, X2 and X4 as ciliate mic; seta X3 absent ( Fig. 18 ). Dorsal cephalic chaetotaxy with 4 antennal (An), 5 sutural (S) mac and 4 (5) mac in Gr. II ( Fig. 19 ).

Th. II with 2 (3) (m1, m2; m 2i only one examined specimen present) medio-medial, 3 medio-lateral mac (m4, m 4i, m4p), 19–23 posterior mac and 3 s-chaetae (ms internal to s); p4 as mac; p5 as mic. Th. III with about 32–34 mac and 2 lateral s-chaetae; p5 as mic ( Fig. 20 ).

Trochanteral organ with about 34 smooth spiny setae ( Fig. 21 ). Inner differentiated tibiotarsal with about 8 “smooth” setae in 2 lines, with ciliations not closely appressed to axis. Unguis with 3 inner teeth; basal paired teeth unequal; outer one larger. Unguiculus acuminate with a large tooth on outer edge. Tenent hair on fore leg pointed, clavate on mid and hind leg (rarely pointed), subequal to unguiculus in length ( Fig. 22 ).

Abd. IV 4.3–4.6 times as Abd. III in length along dorsal midline. Abd. I with 7 (a2, a3, m2–4, m 2i, m4p) mac and 2 s-chaetae (ms external to s). Abd. II with 4–5 (a2, m3, m3e, m3ep; a3 sometimes absent) central, 1 (m5) lateral mac and 2 s-chaetae. Abd. III with 1 (m3) central, 3 (am6, pm6, p6) lateral mac and 3 s-chaetae (1 ms and 2 s, Fig. 23 ). Abd. IV with 7 central, 6 (F1, E2–4, E2p, D3) lateral mac and about 9 elongated s and 2 s of normal length ( Fig. 24 ). Abd. V with 3 s-chaetae; chaetae m2, m3 and m5 always much larger than others ( Fig. 25 ). Tenaculum with 4+4 teeth and one large ciliate seta. Ventral tube anteriorly with 8+8 ciliate setae ( Fig. 26 ); each lateral flap with 9–10 smooth setae (sometimes 1 of them ciliate); posteriorly with distal 4 smooth ( Fig. 27 ). Manubrium without smooth setae. Manubrial plaque with 2 (3) pseudopores and 4 ciliate setae ( Fig. 28 ). Distal smooth part of dens 1.0–1.2 times length of mucro. Mucro bidentate with basal spine with tip reaching apex of subapical tooth ( Fig. 29 ). Genital plate papillate.

Ecology. In the leaf litter and under stone.

Etymology. Named after Mr C. Ge, who collected the specimens.

Remarks. The new species is characterized by ciliate seta R on labial base, abundant spiny setae on trochanteral organ and chaetotaxy of Abd. I and Abd. V. It is most similar to S. umesaoi in eyes number, labial process, chaetotaxy of Abd. II–IV, structure of claw and mucro; however, it could be distinguished from the latter by unpigmented body, ciliate setae R, spiny setae on trochanteral organ, chaetotaxy on Th. II–III and Abd. I. It also differs from another species with 5+5 eyes, S. quinocula Chen & Christiansen, 1993 , by chaetotaxy of Abd. I–III, smooth setae on ventral tube and tenent hair. More details are listed in Table 2.

characters S. gei n. sp. S. umesaoi S. quinocula Maximum body length (mm) 2.7 1.6 1.8 Colour pattern (except eye patches) unpigment grey unpigment Lateral process of labial palp compared with beyond beyond reaching papilla E

Tenent hair on fore leg acuminate acuminate clavate Spiny setae on trochanteral organ about 34 13–15? Setae on anterior face of ventral tube 16 c 14 c 14 c Setae on posterior face of ventral tube 4 s, 8–15 c 11 s? Setae on lateral flap of ventral tube 8–9 s, 0–1 c 9–10 s 7 s Setae on manubrial plaque 4 4 3 Setae R on labial base c s c Mac p4 on Th. II present present absent Mac p 1i 2 on Th. II absent present? Mac a 4i and m 5i on Th. III present present absent Number of mac on Abd. I 7 6 6 Number of mac on Central Abd. II 1 (2) 1 0 Number of mac on Central Abd. III 1 +1 1+1 2+2

Notes: s, smooth; c, ciliate;?, unclear.

Figures

FIGURES 17 – 22. Sinella gei n. sp.: 17, lateral process of labial palp; 18, setae on ventral side of head; 19, dorsal cephalic chaetotaxy; 20, thoracic chaetotaxy; 21, trochanteral organ; 22, hind claw.

FIGURES 23 – 29. Sinella gei n. sp.: 23 – 25, abdominal chaetotaxy: 23, Abd. I – III; 24, Abd. IV; 25, Abd. V; 26 – 27, ventral tube: 26, anterior face; 27, posterior face and lateral flap; 28, manubrial plaque; 29, mucro.