Sinella quinseta, 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 : 32-33

Taxon classification Animalia Collembola Entomobryidae

Sinella quinseta sp. n. Figs 1-14, 15-18

Material.

Holotype: ♀ on slide, China, Jiangsu Province, Nanjing, Purple Mountain, Tomb of Liao Zhongkai and his wife He Xiangning, 32.056°N, 118.830°E, altitude 38 m, 10 April 2009, Feng Zhang and Daoyuan YU leg. (# C9581). Paratypes: 1 ♂ and 4 ♀♀ on slides and 5 juveniles in alcohol, same data as holotype.

Etymology.

Named after the unique 5+5 central mac on Abd. II in this new species.

Diagnosis.

No eyes. Two internal sens of Ant. III organ expanded. Long smooth straight chaetae absent on antennae. Clypeal chaetae 7(5). Postlabial chaetae X, X2 and X4 ciliate. No “smooth” inner differentiated tibiotarsal chaetae. Tenent hairs clavate. Manubrium without smooth chaetae. Tergal ms as 1, 0|1, 0, 0, 0. Abd. II with 5+5 central mac. Abd. IV with 5+5 central and 5+5 lateral mac.

Description.

Body length up to 1.17 mm. Body pale in alcohol.

Antenna 1.69-1.80 times as long as cephalic diagonal. Antennal segments ratio as I: II: III: IV = 1: 2.00-2.17: 1. 82-1.90: 3.12-3.18. 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 S-chaeta. Two internal sens of Ant. III organ expanded (Fig. 1). Long smooth straight chaetae absent on antennae.

Eyes absent. Prelabral and labral chaetae 4/ 5, 5, 4, all smooth; the three median chaetae of the row a longer than lateral ones (Fig. 2). Labral papillae absent. Clypeal chaetae 7(5), arranged in two rows; the inner two chaetae of the anterior row of four chaetae smooth in one specimen; most lateral two small chaetae absent in two specimens (Fig. 3). Dorsal cephalic chaetotaxy with four antennal (An), three median (M) and five sutural (S) mac; Gr. II with four mac (Fig. 4). Mandible teeth 4+5. Subapical chaeta of maxillary outer lobe thicker than apical one and subequal in length; three smooth sublobal hairs on maxillary outer lobe (Fig. 5). Lateral process of labial palp slightly thicker than normal chaetae, with tip beyond apex of labial papilla E (Fig. 6). Labial chaetae as mrel1l2, all smooth, r/m = 0.60-0.68; chaetae X, X2 and X4 ciliate; X2 often absent; chaeta H1 ciliate; H2 smooth in one specimen and ciliate in others. Cephalic groove with 9(8) chaetae, 2(3) smooth and others ciliate (Fig. 7).

Trochanteral organ with 9-13 smooth spiny chaetae; 7-9 in arms and 2-4 between them (Fig. 8). Inner differentiated tibiotarsal chaetae ciliate with ciliations not closely appressed to axis. Tibiotarsi distally with ten chaetae in a whorl. Unguis with three inner teeth; two paired teeth unequal, outer one large. Unguiculus with a large outer tooth. Tenent hairs clavate (Fig. 9). Abd. IV 2.44-3.32 times as long as Abd. III along dorsal midline. Ventral tube anteriorly with 4-5 ciliate chaetae; one of them much larger than others (Fig. 10); posteriorly with 4 smooth chaetae; each lateral flap with 5 smooth and 2 ciliate chaetae (Fig. 11). Manubrium without smooth chaetae. Manubrium anteriorly with 5+5 ciliate chaetae in the most distal row (Fig. 12). Manubrial plaque with 2+2 pseudopores and 2+2 ciliate chaetae (Fig. 13). Distal smooth part of dens 1.34-1.85 times as long as mucro. Mucro bidentate with apical tooth longer than subapical one; basal spine long, nearly reaching tip of the apical tooth (Fig. 14).

Th. II with 3 (m1, m2, m2i) medio-medial, three (m4, m4i, m4p) medio-lateral, 20-22 posterior mac, one ms and two sens; ms inner to sens. Th. III with 29-32 mac and two lateral sens; mac a6i absent (Fig. 15). Abd. I with six (a3, m2-4, m2i, m4p) mac, one ms and one sens; sens inner to ms. Abd. II with five (a2, a3, m3, m3e, m3ep) central, one (m5) lateral mac and two sens. Abd. III with two (a2, m3) central, three (am6, pm6, p6) lateral mac and two sens; ms absent (Fig. 16). Abd. IV with five central (I, M, B4, B5, A6), five lateral mac (E2-4, E2p, F1), and approximately 13 sens; as and ps shorter than others (Fig. 17). Abd. V with three sens; chaeta p5a absent (Fig. 18).

Ecology.

In decomposing leaves along the roads.

Remarks.

Sinella quinseta sp. n. is characterized by blindness, ciliate postlabial chaeta H1 and 5+5 central mac on Abd. II. It is most similar to Sinella yunnanica Zhang & Deharveng, 2011 in being blind, its claw structure, the lateral process of labial palp, mucro, and chaetotaxy of head, thorax and Abd. IV, but differs from it in the presence of expanded internal S-chaetae on Ant. III organ, ciliate H2, X, X2 and X4 posterior to labium, 5+5 central mac on Abd. II, and the ventral tube.