Decapauropus bifurcodicoccus Qian & Dong

Qian, Changyuan, Dong, Yan, Guo, Hua, Chu, Kelin & Sun, Hongying, 2013, Pauropods (Myriapoda: Pauropoda) from eastern China, descriptions of three new species and revision of Pauropus bifurcus Zhang & Chen, 1988, Zootaxa 3608 (2), pp. 116-126 : 119-121

Decapauropus bifurcodicoccus Qian & Dong sp. nov.

( Figure 2 )

Type material. Holotype. ad.9 (female), Laoshan Mountain, Jiangsu, 13 October 2010, leg. Qian et al.

Paratypes. ad.9 (female), Laoshan Mountain, Jiangsu, 24 May 2011, leg. Qian et al.

Diagnosis. The new species may be close to two species previously described from North America and Australia: Decapauropus parkeri Scheller, 2005 from Great Smoky Mountains National Park, USA and Decapauropus saltuarius Scheller, 2009 from Bruny Island, Mount Mangana, Australia. There are similarities especially in the structure of the pygidium, but the new species is distinguished from both these species by the following characters: the length of two branches (length of t is longer than s in D. bifurcodicoccus ; t and s of the same length in D. parkeri and D. saltuarius ); the shape of setae on pygidium (b 1 and b 2 is glabrous in D. bifurcodicoccus ; b 1 and b 2 with striate in D. parkeri and D. saltuatius ); and the shape of the anal plate (V–shaped posterior incision in D. bifurcodicoccus is deeper than that in the other two species; appendages of the anal plate in D. bifurcodicoccus is glabrous, the appendages striate in D. parkeri and D. saltuarius ; appendage length in D. bifurcodicoccus is shorter than for others).

Etymology. From the Latin bifurc - = double forks and dicoccus = two corns (referring to the shape of the anal plate, with two appendages).

Description. Length. 1.2 (–1.9) mm

Head. Tergal setae of short to medium length, subcylindrical, striate, blunt. Relative lengths of setae, 1st row: a 1=(9–)10, a 2=7.7(–9); 2nd row: a 1=7.1–(8), a 2=15.4(–17), a 3=14.6(–16.5); 3rd row: a 1=13.8(–14), a 2=(13–)14.6; 4th row: a 1=(8.7–)10.8, a 2=?(–17.5), a 3=(15–)?, a 4=16.9(–17.8); The ratio a 1/ a 1– a 1 in 1st row 0.81(–0.88), 2nd row 0.36(–0.5), 3rd row (0.75–)0.9 and 4th row 1.2(–1.3). Temporal organs oval in tergal view, their length 2.3 times as long as their shortest distance apart. Head cuticle glabrous.

Antennae. Segment 4 with four cylindrical setae; Relative lengths of setae: p =100, p' =76.7(–81), p'' =(34.9–)37, r =(28–)30; Tergal seta p 1.3(1.2) times as long as tergal branch t. The latter fusiform, 2.7(2.8) times as long as its greatest diameter and 0.96 of length of sternal branch s; that branch 1.8(1.9) times as long as its greatest diameter. Seta q cylindrical, striate, somewhat tapering, 0.93 of length of s. Relative lengths of flagella (basal segments included) and basal segments: F 1=100, bs 1=8(–9); F 2=61(–63), bs 2=8(–10); F 3=(84–)86, bs 3=(7–)9. The F 2 thinnest; F 1 3.3 times as long as t, F 2 and F 3 2.0 (2.1) and 2.9 (2.8) times as long as s, respectively. Distal calyces spherical; distal part of flagella axes fusiform. Globulus g 1.1(1.2) times as long as wide; about nine bracts, capsule subspherical; width of g (0.7)0.8 of the greatest diameter of t. Antennae almost glabrous.

Trunk. Setae of collum segment clavate, striate, rudiments of secondary branches probably absent. Sublateral setae 1.6 times as long as submedian ones; sternite process triangular, blunt; appendages narrowing distally and with flat caps; process and basal segment of appendages with distinct, almost erect, short pubescence. Setae on tergites thin, cylindrical; 4+4 setae on tergite I, 6+6 on II–IV, 6+4 on V, 4+2 on VI. Submedian posterior setae on VI 0.7(–0.8) of their distance apart and about as long as pygidial setae a1. Tergites glabrous. Relative lengths of bothriotricha: T 1=100, T 2=104(–111), T 3=108(–115), T 4=(120–)129, T 5=166(–170), all with simple straight axes; all with pubescence thin, erect.

Legs. Setae on coxa and trochanter of leg 9 furcated with subcylindrical blunt branches. Tarsus of leg 9 short, somewhat tapering, 2.8 times as long as its greatest diameter. Setae subsimilar, thin, cylindrical, striate; their length 0.2 of the length of tarsus. Cuticle of tarsus with very delicate pubescence.

Pygidium. Tergum. Posterior margin between st evenly rounded. Relative lengths of setae: a 1= a 2=100, a 3=181(–185), st =44(–47). All setae but st point, with short oblique pubescence; st blunt, subcylindrical, glabrous; distance a 1 –a 1 as long as a 1; distance a 1– a 2 (1.5–)1.7 times as long as a 2– a 3; distance st – st (4.8)–5.7 times as long as st and 2.1 length of distance a 1– a 1.

Sternum. Posterior margin with shallow indentation between b 1. Relative lengths of setae (a 1=100): b 1=413(–419), b 2=75(–81). All setae subcylindrical, blunt. Distance b 1– b 1 0.72(–0.74) of length of b 1; distance b 1– b 2 0.35(–0.42) of length of b 2.

Anal plate. 2.1 times as long as broad with a V–shaped posterior incision separating two long, subcylindrical posterolateral lobes; lateral margin with indentation, two short, blunt, elliptical, appendages stick out from distal part of lobes, 0.11 of length of the plate; plate and appendages glabrous.

Figures

FIGURE 2. Decapauropus bifurcodicoccus sp. nov. holotype (female). A, head, submedian and right part, tergal view. B, right antenna, tergal view. C, collum segment, median and left part, sternal view. D, tergite VI. E, T 3. F, seta on trochanter of leg 9. G, tarsus of leg 9. H, pygidium, sternal view.