Vitronura paraacuta, Wan, Ya-Ru, Wang, Wen-Bin & Jiang, Jigang, 2016

Vitronura paraacuta sp. nov.

Figs 1–7 View FIGURE 1 View FIGURES 2 – 7 , Tab. 1–2 View TABLE 1 View TABLE 2 , 5 View TABLE 5

Type material. Holotype (female) and 7 paratypes ( 5 females and 2 males) on slides, China, Hunan Province, Changde City, Hefu forest park (29º03’021”N, 111º39’932”E), ca 50m a.s.l., under leaves at a small ditch in forest, 7.iv.2011, leg.: JiGang Jiang, Ya-Ru Wang and Wan-Jun Yu (collection number: J2012040701). All types deposited in Zoology Key Laboratory of Hunan Higher Education, Hunan University of Arts and Science, Changde, China.

Description. Body length: 1.7–2.6 mm ( holotype: 2.2 mm). Body color: red alive and white in alcohol.

Head: eyes 2+2 ( Fig. 1 View FIGURE 1 ). Antenna equal to diagonal of the head. Ant. I and II with 7 and 12 chaetae respectively. Ant. III dorsally fused to Ant. IV. Ant. III organ consists of 2 short microsensilla and 2 long sensilla (sgd and sgv); ventral ms present. Ant. IV with trilobed apical bulb, dorsally with 8 S, i -chaeta, 12 mou, 5 chaetae d and or ( Fig. 2 View FIGURES 2 – 7 ). Labrum distally not ogival, chaetotaxy as 0/2, 2( Fig. 6 View FIGURES 2 – 7 ). Labium with 2 x and 11 Chaetae ( Fig. 5 View FIGURES 2 – 7 ). Mandible with 4 teeth ( Fig. 3 View FIGURES 2 – 7 ). Maxilla crochet-like ( Fig. 4 View FIGURES 2 – 7 ). Cephalic tubercles and chaetotaxy see Fig. 1 View FIGURE 1 and Tab. 1 View TABLE 1 , dorsal macrochaetae and mesochaetae similar to those on thorax and abdomen; almost smooth with hyaline sheath and apically blunt. Microchaetae smooth and sharp. All dorsal cephalic tubercles (except L+So) independent. Tubercle Cl with 2 Mc and 2 me. Tubercle An with 1 Ml and 3 me. Tubercle Fr with 2 Ml and 1 Mc (O-chaeta). Tubercle Di on head with 1 Ml, and De with 1 Ml and 2 me. Tubercle Dl with 1 Ml and 3 me. Tubercle L+So with 3 Ml and 5 me.

Thoracic and abdominal tubercles and chaetotaxy shown in Figs. 1 View FIGURE 1 , 7 View FIGURES 2 – 7 and Tab. 2 View TABLE 2 . Chaetae formula of tubercle Di on Th. I–Abd. V as 1, 3, 3/2, 2, 2, 2, 3. Sensory chaetae and s-microchaeta formula on Th. I–Abd. V as 0, 2+ms, 2/1, 1, 1, 1, 1. Di tubercle on Abd. V with 1 Ml, 2 me ( Fig. 1 View FIGURE 1 ). Each tubercle on Abd. VI with 7 chaetae (4 Ml and 3 me).

Appendages: Ventral tube with 4+4 chaetae ( Fig. 7 View FIGURES 2 – 7 ). Furcal vestige with 5 (sometimes 4) chaetae ( Fig. 7 View FIGURES 2 – 7 ). Unguis with an inner tooth and without lateral tooth. Chaetotaxy of legs, ventral tube and furcal rest shown in Tab. 2 View TABLE 2 .

Etymology. The name of the new species derived from its similarity of chaetotaxy to North Korean species V. acuta Deharveng & Weiner, 1984 .

Terga Legs Remarks. This new species is most similar to V. a c ut a Deharveng & Weiner, 1984, but it differs by the bigger size (1.7–2.6 mm vs. 1.2 mm); trilobed apical bulb of Ant. IV ( vs. simple or bilobated in the latter); mandible with 4 teeth ( vs. 3 teeth in the latter); claw with inner tooth ( vs. claw without inner tooth in the latter), group Ve on Abd. IV with 7–8 chaetae ( vs. 10 chaetae to the latter). Diagnostic characters between the new species and some similar species of the genus are presented in Tab. 5 View TABLE 5 .