Two new species of the genus Sinella Brook, 1882 (Collembola: Entomobryidae) from East China Author Qu, Jiqiang Author Zhang, Feng Author Chen, Jian-Xiu text Journal of Natural History 2010 2010-10-12 44 41 - 42 2535 2541 http://dx.doi.org/10.1080/00222933.2010.499576 journal article 10.1080/00222933.2010.499576 1464-5262 5210587 Sinella hexaseta sp. nov. ( Figure 1 , Table 1 ) Types Female holotype and three female paratypes . China : Anhui Province , Yi County , Taoyuandong village , in and under rotting timbers, 19 October 2004 , J. Qu . Description Body length. Up to 1.43 mm . Colour. White to pale yellow. Head. Eyes absent. Antennae 1.6–1.9 times as long as cephalic diagonal. Ant. III organ with setae 2 and 3 rod-like, others not clearly seen. Apical bulb absent on Ant. IV. Labral setae 4/5, 5, 4, all smooth; labral papillae absent. Lateral process of labial palp slightly thicker than normal setae with tip exceeding apex of same papilla by 0.14–0.16 of its length ( Figure 1A ). Labial setae M 1 REL 1 L 2 all smooth; seta R about 0.84–0.88 as long as seta M 1 . Postlabial setae G 1–4 and H 1–4 smooth; seta X smooth, X 2 weakly ciliate, X 3 weakly ciliate, respectively 0.27–0.29, 0.54–0.62, 0.28–0.36 as long as seta R; X 4 not clearly seen ( Figure 1B ). Dorsal cephalic chaetotaxy with four macrochaetae in Gr. I and four in Gr. II ( Figure 1C ). Thorax. Th. II with three (m1, m2, m2i) macrochaetae in Gr. I, three (a5, m4, m4p) in Gr. II, three (p1a, p1, p1i) in Gr. III, five or six in Gr. IV, five plus five in Gr. V and one (p4) in Gr. VI; Th. III with 9–11 in Gr. I, 9–11 in Gr. II, three (m5, a6i, a6) in Gr. III, three (m6, p5, p6) macrochaetae and three (m6ai2, m6e, m6p) mesochaetae in Gr. IV ( Figure 1D ). Abdomen. Abd. I with six (m2i, m2, m3, m4, m4p, a3) macrochaetae; Abd. II with three (m3e, m3ep, m3) in m3 arch and one (m5) lateral macrochaeta; Abd. III with one (m3) central and two (am6, pm6) lateral macrochaetae ( Figure 1E ); Abd. IV with six (A3, A4, A6, B4, B5, C1) central and five (E2, E2p, E3, E4, D3) lateral macrochaetae ( Figure 1F ). Appendages. Trochanteral organ with 16 setae seen in holotype . Inner differentiated setae of tibiotarsus ciliate with ciliations moderatedly appressed to setal axis. Outstanding inner macrochaeta of hind tibiotarsus at about 0.25–0.35 distance from base, basal half somewhat swollen, distal half gradually tapered and strongly tapered at extreme tip. Unguis with three inner teeth, basal paired two unequal, outer one obviously larger with tip reaching 0.53–0.59 distance from base to tip of inner edge; odd tooth 0.69–0.74 from base. Unguiculus with large outer tooth. Tenent hair longer than unguiculus, with tip acuminate ( Figure 1G ). Ventral tube with 12 smooth setae on posterior face and six smooth setae on each lateral flap ( Figure 1H ); anterior face not clearly seen. Manubrium without posterior smooth setae. Manubrial plaque with three ciliate setae and two pseudopores on each side ( Figure 1I ). Distal smooth part of dens about 1.25–1.40 times as long as mucro. Mucronal apical tooth about 1.41–1.61 times as long as subapical tooth, distal base of latter at about 0.65–0.70 of mucro. Mucronal basal spine long, with tip about reaching apex of apical tooth ( Figure 1J ). Figure 1. Sinella hexaseta sp. nov. (A) Lateral process of labial palp; (B) setae on labial base; (C) dorsal cephalic chaetotaxy; (D) dorsal thoracic chaetotaxy; (E, F) dorsal abdominal chaetotaxy; (G) hind foot; (H) posterior face of ventral tube and lateral flap; (I) manubrial plaque; (J) mucro. Symbols used for setae in (C–F): full circle: macrochaeta; circle with diagonal line: pseudopore; cross: bothriotrichum. Table 1. Comparison among Sinella hexaseta , Sinella insolens and Sinella christianseni .

Characters	S. hexaseta	S. insolens	S. christianseni
X3 on ventral head	weakly ciliate	ciliate	absent
m4i on Th. II	absent	present	absent
m5i on Th. III	absent	present	absent
a2 on Abd. I	absent	present	absent
m3 on Abd. II	absent	present	absent
Dorsocentral chaetotaxy on Abd. IV	6+6, pattern II	7+7, pattern I	5+5, pattern IV
Outer tooth on unguiculus	absent	present	absent
Smooth setae on manubrium	absent	absent	present
Mucronal basal spine	long	long	short
Tenent hair	acuminate	acuminate	clavate

Etymology The name of the new species is derived from Latin hex and seta referring to the existence of 6+6 central macrochaetae on Abd. IV. Remarks The new species differs from all known species of the genus by the Abd. IV with unique dorsocentral chaetotaxic pattern, which was designated by Chen and Christiansen (1993) as pattern II, but has not been recorded in any known Sinella species. So far, 18 blind Sinella species have been reported all over the world. Among them, two Chinese species, Sinella insolens Chen and Christiansen, 1993 and Sinella christianseni Ma and Chen, 1997 , share many characters with the new species, but differ from the latter in some important characters. A comparison of the three species is given in Table 1 .