Stachorutes cuihuaensis, Gao & Yin, 2007

GAO, YAN & YIN, WENYING, 2007, A new species of the genus Stachorutes Dallai, 1973 from China (Collembola, Neanuridae), Zootaxa 1469 (1), pp. 65-68 : 65-67

Stachorutes cuihuaensis sp. nov.

Figs 1 –12

Type material. Holotype: female on slide, northwest China, Shaanxi Province, Cuihua Mountain , 1400 m a.s.l., litter-rich soil in forest, 8 /6 / 2006, coll. Yun-Xia Luan, Yun Bu and Yan Gao. Paratypes: 3 females and 2 males on slides, the same data as holotype. Type material is deposited at the Insect Specimen Gallery, Institute of Plant Physiology and Ecology , Shanghai Institutes for Biological Sciences , Chinese Academy of Sciences .

Description. Habitus typical of the genus Stachorutes Dallai, 1973 (Fig. 1). Body length (without antennae) 600– 850µm (holotype: 720µm). Colour of the body grey, eyes dark. Cuticular granulation fine, homogenous.

Antennae length 120µm in holotype, shorter than head, cephalic diagonal length 220µm. Antennal segment I with 7 setae; antennal segment II with 12 setae; Antennal segments III and IV fused dorsally; length ratio of antennal segment I: II: II + IV as 1: 1.1: 2.8. Antennal III-organ with two small internal curved sensilla and two larger guard sensilla (Figs 2– 3). There has one microsensillum beside the ventral guard sensilla (Fig. 3). Antennal segment IV with large simple apical bulb, seta i and 6 cylindrical sensilla (Fig. 2). Ventral chaetotaxy of antennal segment IV as in Fig. 3 .

Postantennal organ elliptical, composed of 9 simple vesicles, 2.7 times larger than ocelli (Fig. 4). Eyes consist of 5+5 small ocelli (Fig. 4), about as large as skin granules, hard to detect. Buccal cone exceptionally elongated (labrum not clearly visible). Mandible with three teeth, maxilla styliform (Fig. 5). Labium with 4+4 distal and 8+8 proximal setae, setae L absent (Fig. 6).

Dorsal chaetotaxy as in Fig. 1. Seta a0 on the head present, unpaired seta d1 present. Thoracic tergum I with 3+3 setae. Setae a2 absent on the thoracic terga II and III. Setae s (setae sensuales) on the body in position of p3 and m7 on the thoracic terga II and III, p4 on abdominal terga I to IV and p2 on abdominal tergum V. Sensorial formula of the body: 022/11111. Setae s more than twice longer than ordinary setae. Thoracic sterna without setae, ventral tube with 4+4 setae (Fig. 7).

Furcula present, length 45µm. Manubrium length 13µm. Dens length 24 µm, with 6 setae. Mucro 3 times shorter than dens, triangular in shape (Fig. 8). Tenaculum with 3+3 teeth (Fig. 9). Genital apertures of female with 9 setae (Fig. 10) and male with 12 setae (Fig. 11).

Tibiotarsi I, II, III with 19, 19, 18 setae respectively, tenent hairs absent. Femora I, II and III with 12, 12 and 11–12 setae respectively, trochanters I, II and III with 6, 6 and 6 setae respectively, coxae I, II and III with 3, 6 and 6 setae respectively and 2.subcoxae I, II and III with 0, 3 and 3 setae respectively, 1.subcoxae with 1, 1–2 and 2 respectively. Unguis length 15µm. Claw inner tooth and unguiculus absent (Fig. 12).

Variation. One specimen observed with 6 setae on the segment I of the right antenna.

Discussion. The new Stachorutes species resembles S. navajellus Fjellberg, 1984 in having 5+5 ocelli, no setae a0 on head and dens with 6 setae. However, S. cuihuaensis sp. nov. differs from it by tenaculum tooth number (2+2 teeth in S. navajellus ) and the absence of seta a2 on thoracic tergum II (present in S. navajellus ). S. cuihuaensis is also close to S. scherae Deharveng & Lienhard, 1983 and S. longirostris Deharveng & Lienhard, 1983 with 5+5 ocelli and dens with 6 setae, but the new species differs from them by the chaetotaxy: seta a0 on head absent and seta a2 on thoracic tergum II present in S. scherae ; seta a0 on head absent and thoracic tergum I with 2+2 setae in S. longirostris .

Etymology. The species is named after the type locality: Cuihua Mountains, Shaanxi Province, China.