Sinella qixiaensis, Xu, Heng & Zhang, Feng, 2016

Xu, Heng & Zhang, Feng, 2016, New blind species and new records of Sinella from Nanjing, China (Collembola, Entomobryidae), ZooKeys 604, pp. 31-40 : 34-36

Taxon classification Animalia Collembola Entomobryidae

Sinella qixiaensis sp. n. Figs 19-30, 31-37

Material.

Holotype: ♂ on slide, China, Jiangsu Province, Nanjing, Qixia Mountain, 32.160°N 118.960°E, altitude 114 m, 6 December 2014, Daoyuan Yu and Chunyan Qin leg. (#14NJQX4). Paratype: 4 ♀♀ on slides and 5 in alcohol, same data as holotype.

Etymology.

Named after the type locality.

Diagnosis.

No eyes. Two internal sens of Ant. III organ paddle-like. Long smooth straight chaetae present on antennae. Clypeal chaetae eight. Postlabial chaetae X and X2-4 ciliate. “Smooth” inner differentiated tibiotarsal chaetae present. Tenent hairs I and II pointed or clavate, and III always clavate. Manubrium with smooth chaetae. Tergal S-microchaetae as 1, 0|1, 0, 0, 0. Abd. II with 4(3) central mac on each side. Abd. IV with 7+7 central and 6+6 lateral mac.

Description.

Body length up to 2.01 mm. Body pale in alcohol.

Antenna 2.41-2.68 times as long as cephalic diagonal. Antennal segments ratio as I: II: III: IV = 1: 1.66-1.96: 1. 59-1.83: 2.44-3.00. Smooth spiny mic at base of antennae three dorsal, three ventral on Ant. I, one internal, one external and two ventral on Ant. II. Ant. II distally with two rod-like sens. Two internal sens of Ant. III organ paddle-like (Fig. 19). Ant. IV with a knobbed subapical organ. Long smooth straight chaetae at least five ventral on Ant. I, at least 13 ventral on Ant. II, and one ventral on Ant. III.

Eyes absent. Prelabral and labral chaetae 4/ 5, 5, 4, all smooth; median three chaetae of the row a longer than lateral ones; labral intrusion not U-shaped (Fig. 20). Labral papillae absent. Clypeal chaetae eight in number, of which three are ciliated and small (Fig. 21). Dorsal cephalic chaetotaxy with four antennal (An), three median (M) and five sutural (S) mac; Gr. II with 5-6 mac (Fig. 22). Mandible teeth 4+5. Subapical chaeta of maxillary outer lobe larger than apical one; three smooth sublobal hairs on maxillary outer lobe. Lateral process of labial palp slightly thicker than normal chaetae, with tip beyond apex of labial papilla E (Fig. 23). Labial chaetae as mrel1l2, all smooth, r/m=0.61-0.76; chaetae X and X2-4 ciliate; chaeta X3 rarely absent. Cephalic groove with 8-9 chaetae, 4(5) of them smooth and others ciliate (Fig. 24).

Trochanteral organ with approximately 24 smooth spiny chaetae; 13-15 in arms and 9-11 between them (Fig. 25). Partial inner differentiated tibiotarsal chaetae “smooth” with ciliations closely appressed to axis. Tibiotarsi distally with ten chaetae in a whorl. Unguis with three inner, one outer, and two lateral teeth; two paired inner teeth unequal, outer one large. Unguiculus with a large outer tooth. Tenent hairs I and II pointed or clavate, and III always clavate (Fig. 26). Abd. IV 3.13-4.67 as long as Abd. III along dorsal midline. Ventral tube anteriorly with 6+6 ciliate chaetae, two of them much larger than others (Fig. 27); posteriorly with 12 smooth chaetae (Fig. 28); each lateral flap with eight smooth chaetae (Fig. 29). Male genital plate with seven pairs of projections and internally with one pair of small chaetae (Fig. 30). Manubrium dorsally with about 13+13 smooth chaetae (Fig. 31); ventrally with 5+5 distal ciliate chaetae (Fig. 32). Manubrial plaque with 3+3 pseudopores and 3+3(2) ciliate chaetae. Base of dens with 2+2 smooth chaetae (Fig. 31). Distal smooth part of dens 1.04-1.12 as long as mucro. Mucro bidentate with apical tooth larger; basal spine long, with tip nearly reaching apical tooth (Fig. 33).

Th. II with three (m1, m2, m2i) medio-medial, three (m4, m4i, m4p) medio-lateral, 22-24 posterior mac, one ms and two sens; ms inner to sens. Th. III with 30-34 mac and two lateral sens; m5i, a6i, p5, p6, m6 and m6e as mac (Fig. 34). Abd. I with seven (a2-3, m2-4, m2i, m4p) mac, one ms and one sens; sens inner to ms. Abd. II with 4(3) (m3, m3e, m3ep, m3ei) central, one (m5) lateral mac and two sens; mac m3ei only absent on one side of one specimen. Abd. III with one (m3) central, three (am6, pm6, p6) lateral mac and two sens; ms absent (Fig. 35). Abd. IV with seven central (I, M, A5-6, B4-6), six lateral mac (D3, E2-4, E2p, F1), and at least 17 sens; sens as and ps short (Fig. 36). Abd. V with 3 sens (Fig. 37).

Ecology.

In decomposing leaves along the roads.

Remarks.

Sinella qixiaensis sp. n. is characterized by blindness, the paddle-like sens of Ant. III organ and abundant smooth chaetae on the manubrium. It is most similar to Sinella insolens Chen & Christiansen, 1993 and Sinella sineocula Chen & Christiansen, 1993. It differs from the former in the presence of smooth manubrial chaetae and the absence of labial chaeta M1s, and also differs from Sinella sineocula in the presence of smooth manubrial chaetae, the paddle-like sens of Ant. III organ, and the presence of mac m3ei on Abd. II.