Sinella abietis sp. nov.

Figs 1, 11–27, Table 1

Types. Holotype: male on slide, China: Zhejiang Province: Qingyuan County: Baishanzu Natural Reserve, alt. 1149 m, 27.739°N, 119.179°E, 22.v.2011, Feng Zhang and Daoyuan YU leg. (# C9662). Paratypes: three females on slides, same data as holotype.

Description. Body length up to 1.33 mm. Body light orange in alcohol (Fig. 1).

Antenna 1.8 of cephalic diagonal length. Antennal segments ratio as I: II: III: IV = 1: 1.67–1.87: 1. 27–1.53: 2.67–2.93. Smooth spiny mic at base of antennae 3 dorsal, 3 ventral on Ant. I, 1 internal, 1 external and 1 ventral on Ant. II. Ant. II distally with 1 sens having basal part expanded (Fig. 11). Two internal sens of Ant. III organ paddle-like; chaeta 8 dagger-like (Fig. 12). Ant. IV with a knobbed subapical organ (Fig. 13); 2 extero-dorsal short sens as those on Ant. II distally (Fig. 11), 0.17 and 0.45 distance from the apex, respectively. Long smooth straight chaetae absent on antennae.

Eyes 1+1. Prelabral and labral chaetae 4/ 5, 5, 4, all smooth; the five chaetae of the first row subequal in length. Seven ciliate clypeal chaetae arranged in two rows (Fig. 14). Dorsal cephalic chaetotaxy with 4 antennal, 3 median (M) and 5 sutural (S) mac; Gr. II with 3–4 mac (Fig. 15). Subapical chaeta of maxillary outer lobe slightly thicker than apical one; 3 smooth sublobal hairs on maxillary outer lobe. Lateral process of labial palp as thick as normal chaetae, with tip not reaching apex of labial papilla (Fig. 16). Labial chaetae as mrel1l2, all smooth, r/m=0.8; chaetae X, X2, X4, H1, and H4 ciliate. Chaetae along cephalic groove 6–7, the proximal one smooth and others ciliate (Fig. 17).

Trochanteral organ with 12–16 smooth spiny chaetae; 10–13 in arms and 2–4 between them (Fig. 18). Inner differentiated tibiotarsal chaetae ciliate with ciliations not closely appressed to axis. Tibiotarsi distally with 11 chaetae in a whorl. Unguis with 3 inner teeth; 2 paired teeth unequal, outer one large. Unguiculus outer edge smooth. Tenent hairs pointed (Fig. 19). Abd. IV 3.2–5.1 of Abd. III dorsal midline length. Ventral tube anteriorly with 6+6 ciliate chaetae and 1+1 pseudopore; two of them much larger than others (Fig. 20); posteriorly with 14 chaetae, 4 apical ones smooth and others weakly ciliate; each lateral flap with 7 smooth and 2 ciliate chaetae (Fig. 21). Manubrium without smooth chaetae. Manubrial plaque with 3+3 pseudopores and 3+3 ciliate chaetae (Fig. 22). Distal smooth part of dens 2.0 of mucro length. Mucro bidentate with two teeth subequal; basal spine reaching tip of the subapical tooth (Fig. 23).

Th. II with 3 (m1, m2, m 2i) medio-medial, 3 (m4, m 4i, m4p) medio-lateral, 24–25 posterior mac, 1 ms and 2 sens; ms inner to sens. Th. III with 25–26 mac and 2 lateral sens; a 6i, p6 and m6 as mac (Fig. 24). Abd. I with 6 (a3, m2–4, m 2i, m4p) mac, 1 ms and 1 sens; sens inner to ms. Abd. II with 3 (m3, m3e, m3ep) central, 1 (m5) lateral mac and 2 sens. Abd. III with 1 (m3) central, 2 (pm6, p6) lateral mac and 2 sens; ms absent (Fig. 25). Abd. IV with 4 central (M, B5, B6, A6) and 6 lateral mac (D3, E2–4, E2p, F1) (Fig. 26); two sens (as, ps) of normal length and others elongate. Abd. V with 3 sens (Fig. 27).

Ecology. Leaves in decomposition along the roads.

Etymology. Named after the famous national key protected wild plants Abies beshanzuensis in natural reserve.

Remarks. S. abietis sp. nov. is characterized by 1+1 eyes, paddle-like sens of Ant. III organ, ciliate clypeal chaetae, ciliate chaetae X, X2, X4, H1, and H4 posterior to labium, 2+2 lateral mac on Abd. III, 4+4 central mac on Abd. IV, and smooth outer edge on unguiculus. It is most similar to S. affluens Chen & Christiansen, 1993, but differs from it in having ciliate H4, X, and X4 posterior to labium, smooth outer edge on unguiculus, short mucronal spine, three pseudopores on manubrial plaque, 2+2 lateral mac on Abd. III, and chaetotaxy of Abd. IV. The new species differs from another 1+1 eyed species S. fuyanensis in having paddle-like sens of Ant. III organ, ciliate H4, X, X2, and X4 posterior to labium, 3+3 chaetae and 3+3 pseudopores on manubrial plaque, longer smooth part of dens, p5 as mic on Th. III, 2+2 lateral mac on Abd. III, and 4+4 central mac on Abd. IV (Table 1).

Types. Holotype: female on slide, China: Shanxi Province: Mishui county: Zhongshan town: Lishan National Natural Reserve, alt. 1469 m, 35.42806°N, 112.00194°E, 11.ix.2013, F. Zhang leg. (# 13SXLS2). Paratype: female on slide, alt. 1494 m, 35.43556°N, 112.01194°E, 12.ix.2013 (# 13SXLS4), other data same as holotype.

Description. Body length up to 1.07 mm. Orange pigments weakly scattered on head and body (Fig. 2).

Antenna 1.5–1.9 of cephalic diagonal length. Antennal segments ratio as I: II: III: IV = 1: 2.0: 1. 4: 3.7. Smooth spiny mic at base of antennae 3 dorsal, 3 ventral on Ant. I, 1 internal, 1 external and 1 ventral on Ant. II. Ant. II distally with 1 rod-like, unexpanded sens. Two internal sens of Ant. III organ rod-like; chaeta 8 posterior to chaeta 9 (Fig. 28). Long smooth straight chaetae absent on antennae.

Eyes 1+1. Prelabral and labral chaetae 4/ 5, 5, 4, all smooth. Clypeal chaetae 8, all ciliate (Fig. 29). Dorsal cephalic chaetotaxy with 4 antennal, 3 median (M) and 4 sutural (S) mac (Fig. 30). Subapical chaeta of maxillary outer lobe thicker than apical one; 3 smooth sublobal hairs on maxillary outer lobe (Fig. 31). Lateral process of labial palp as thick as normal chaetae, with tip beyond apex of labial papilla (Fig. 32). Labial chaetae as mRel1l2, all smooth except R, R/m=0.7; chaetae G1-3 smooth and others ciliate. Cephalic groove with 7 chaetae, 1 (G1) of them smooth (Fig. 33).

Trochanteral organ with 10–12 smooth spiny chaetae; 7–9 in arms and 3 between them. Inner differentiated tibiotarsal chaetae ciliate with ciliations not closely appressed to axis. Tibiotarsi distally with 10 ciliate chaetae in a whorl. Unguis with 3 inner teeth; 2 paired teeth unequal, outer one large. Unguiculus outer edge with a large tooth. All tenent hairs pointed (Fig. 34). Abd. IV 2.4–2.6 of Abd. III dorsal midline length. Ventral tube anteriorly with 2+2 large and 4+4 small ciliate chaetae (Fig. 35); posteriorly with 9 (3, 2, 4 in three rows) chaetae, the extero-apical two ciliate (Fig. 36); each lateral flap with 7 chaetae, 3 of them ciliate (Fig. 35). Manubrium without smooth chaetae. Manubrial plaque with 2+2 pseudopores and 2+2 ciliate chaetae. Distal smooth part of dens 2.3–2.7 of mucro length. Mucronal basal spine nearly reaching tip of the apical tooth (Fig. 37).

Th. II with 4 (m1, m2, m 2i, m 2i 2) medio-medial, 3 (m4, m 4i, m4p) medio-lateral, 18–20 posterior mac, 1 ms and 2 sens; ms internal to sens; mac p2ep2 often absent. Th. III with 25 mac and 2 lateral sens; mac a 6i and m 5i absent (Fig. 38). Abd. I with 6 (a3, m2–4, m 2i, m4p) mac, 1 ms and 1 sens; ms inner to sens. Abd. II with 5 (a2, a3, m3, m3e, m3ep) central, 1 (m5) lateral mac and 2 sens. Abd. III with 2 (a2, m3) central, 1 (pm6) lateral mac and 2 sens. Abd. IV with 4 central (M, B5–6, A4), 5 lateral mac (D3, E2–4, F1) and at least 9 sens; two sens of normal length and others elongate (Fig. 39). Abd. V with 3 sens (Fig. 40).

Ecology. In rotten leaves of forest.

Etymology. Named after the 1+1 lateral mac on Abd. III.

Remarks. S. uniseta sp. nov. is the eighth species with 1+1 eyes from China (Zhang, 2013). It is characterized by the reverse position of chaetae 8 and 9 on Ant. III, 4 sutural cephalic mac, 1+1 lateral mac on Abd. III, and unique 4+4 central and 5+5 lateral mac on Abd. IV. It is most similar to S. affluens Chen & Christiansen, 1993 in 1+1 eyes, long mucronal spine nearly reaching the tip of the apical tooth and claw structure, but differs from the latter in having ciliate chaetae posterior to G1-3, Ant. III organ, absence of mac a 6i on Th. III, 5+5 central mac on Abd. II, 2+2 central and 1+1 lateral mac on Abd. III, unique arrangement of central mac on Abd. IV, and pointed tenent hair.