Stylopauropus plicatus, Scheller, Ulf, 2011

Scheller, Ulf, 2011, Pauropoda (Myriapoda) from Great Smoky Mountains National Park, U. S. A., with descriptions of four new species, Zootaxa 2962, pp. 36-48 : 40-42

Stylopauropus plicatus n. sp.

Figs 12–20

Type locality. U.S.A., Tennessee, Blount Co., Great Smoky Mountains National Park, Reed Creek.

Type specimens. Holotype: ad. 9 (Ƥ), 27 June 1997, leg. P.J. Obenauer. Paratypes: 1 ad. 9(3), 1 subad. 8(Ƥ), 1 juv. 5, Tennessee, Blount Co., Great Smoky Mountains National Park, Cades Cove, Parsons Branch Road, 5 minutes from Jet Force Creek Road, hemlock log litter, 35º 37.75N, 83º 51.62W, 28 July 2004, leg. S.A. Gil & J. Hilten; 1 ad. 9(Ƥ), North Carolina, Swain Co., Lakeshore Trail, Pilky Creek, UTM 0 2 57 998E, 39 25 761N, 14 April 2004, leg. A.J. Mayor.

Nontypes: Tennessee, Blount Co., lower Gregory Ridge trail, 1 mile from trail-head, litter, Berlese extraction, 1 subad. 8(Ƥ), 28 July 2004, leg. A.K. Tishechkin & B. Blitz; Cooper Road Trail, 0.8 miles from trail-head, elev. 1211 ft, 35º 37.021N, 83º 55.608W, 1 subad. (Ƥ), 31 July 2004, leg. J. Ceigier & S.A. Gil. Sevier Co., Cades Cove, Crooked Arm Ridge Trail, 35º 36.659N, 83º 46.796W, conifer cones, Berlese extraction, 2 subad. 8(Ƥ), 31 July 2004, leg. B. Blitz & V.M. Bayless. – 9 specimens.

Diagnosis. S. plicatus n. sp. belongs to a group of Nearctic species related by similarities in the general shape of the anal plate, subsimilar shape and length of the pygidial setae a 1, a 2 and a 3 and antennal globulus with a strikingly high number of bracts: S. californianus Remy , S. fratuelis Remy, S. canadensis Scheller and S. boreus Scheller. The first is widely distributed, known from NE Siberia ( Scheller 1986), California ( Remy 1958), British Columbia ( Scheller 1984) and the southern Appalachians. The other three have, as far as we know now, restricted ranges. Thus S. boreus Scheller is known only from Alaska ( Scheller 1986), S. fratuelis Remy only from Tennessee ( Remy 1958) and S. canadensis Scheller only from British Columbia ( Scheller 1984). The new species can be distinguished from these species particularly by the shape of the styli of the pygidial tergum (thin and pointed, not more or less thick and blunt) and by the shape of the anal plate (posteriorly directed submedian branches parallel and very close to each other, not diverging). Similarities can be traced in the direction of the two Alaskan species S. longipes Scheller and S. longitarsus Scheller (Scheller 1986) but to a lesser degree.

Derivation of name. From the Latin plicatus = fold (referring to the longitudinal folds of the anal plate). Description. Length. (0.89–) 0.99 mm.

Head ( Fig. 12 ). Tergal setae pubescent, median and submedian setae clavate, lateral and sublateral ones cylindrical, blunt, a 3 in 2nd row and l -group setae tapering pointed. Relative lengths of setae (holotype only), 1st row: a 1=10; a 2=11; 2nd row: a 1=11, a 2=12, a 3=18; 3rd row: a 1= a 2=10; 4th row: a 1=12, a 2=16, a 3=18, a 4 = 10; l 1= l 3=15, l 2=?. The ratio a 1 /a 1 -a 1 in 1st row 1.4, 2nd row 0.6, 3rd row 0.7, 4th row 1.5. Temporal organs mainly lateral, their length in tergal view 0.7 of shortest interdistance. Head cuticle glabrous.

Antennae ( Fig. 13 ). Segment 3 with 3 setae and rudimentary, almost cylindrical, globulus g´on distal part of tergal side. Segment 4 with at least 3 cylindrical striate setae, r thinnest. Relative lengths of setae (holotype only): p = 100, p ' = 73, r = 15. Tergal seta p 1.1 times as long as tergal branch t. The latter cylindrical, (4.5)4.9 times as long as its greatest diameter and as long as sternal branch s which is 2.3 times as long as its greatest diameter and with its posterodistal corner distinctly truncate. Seta q as tergal-anterior setae of 4th segment, 1.1 times as long as s. Relative lengths of flagella (with base segments included) and base segments: F 1=100, bs 1=6, F 2=90, bs 2=6, F 3=50, bs 3=5. F 1 2.7(2.9) times as long as t, F 2 and F 3 2.5 and 1.4 times as long as s respectively. Distal calyces of F 1 conical, longer than wide, glabrous, other calyces not studied. Globulus g 1.8 times as long as its greatest diameter; (16)19 bracts; capsule spherical. Diameter of g 2.7 times as long as greatest diameter of t. Antennae glabrous.

Trunk ( Figs 14, 15 ). Setae of collum segment ( Fig. 14 ) leaf-shaped, blunt, shortly pubescent, furcate with rudimentary secondary branch, the latter blunt glabrous. Sternite process triangular, anterior part incised; appendages broadly conical with thick caps. Pubescence faint on appendages, distinct on anterior part of process.

Setae on tergites only partly studied. 4+4 setae on tergite I, 6+6 setae on II–V, 4+2 on VI. Posterior setae on VI ( Fig. 15 ) long tapering, 1.5 times as long as interdistance and 2.3 times as long as pygidial setae a 1. Tergites glabrous.

Genital papillae (fig. 16). 1.7 and 2.0 times as long as greatest width, proximal half cylindrical, seta 0.4 of the length of papilla.

Bothriotricha. Most bothriotricha lost or broken. Relative lengths: T 1 = 100, T 5 = 244(–324). Axes simple straight; pubescence consisting of simple straight hairs, oblique on most proximal parts, outwards erect.

Legs. Setae on coxa ( Fig. 17 ) and trochanter of legs 1–8 leaf-shaped blunt, very shortly pubescent, secondary branch rudimentary glabrous; these setae on leg 9 furcate with secondary branch clavate, shortly pubescent, 0.8 of the length of seta. Tarsus of leg 9 ( Fig. 18 ) somewhat bow-shaped, tapering, (4.7)4.8 times as long as its greatest diameter. Proximal seta long tapering pointed, with short oblique pubescence, seta (0.6)0.7 of the length of tarsus and (4.2)4.3 times as long as distal seta, the latter cylindrical blunt striate. Cuticle of tarsus weakly pubescent.

Pygidium ( Figs 19, 20 ). Tergum. Posterior part broadly triangular, distinct semicircular posterior lobe between st. Setae thin with short oblique pubescence; their relative lengths: a 1=10, a 2=9(10), a 3=10(11), st =5; a- setae directed posteriorly, somewhat curved inwards, subcylindrical, in distal half tapering, st straight tapering pointed, distinctly converging. Distance a 1 -a 1 0.7 of interdistance, distance a 1 -a 2 1.7(2.0) times as long as distance a 2- a 3; distance st-st (1.7)1.8 times as long as st and (1.2)1.3 times as long as distance a 1 -a 1. Cuticle glabrous.

Sternum. Setae b 1 on small lobes, posterior margin in between almost straight. Relative lengths of setae (pygidial a 1=10): b 1=20. b 1 subcylindrical blunt, with short oblique pubescence, 1.3 times as long as interdistance.

Anal plate narrowest anteriorly, as broad as long, lateral margins convex, posterior corners lengthened into short tapering, posteriorly directed, points; posterior margin with two submedian subcircular indentations and between them two long appendages protruding backwards close to each other; appendages as long as plate, cylindrical tapering. Plate and appendages glabrous.

Figures

FIGURES 12 – 20. Stylopauropus plicatus sp. n., holotype (Ƥ) 12 – 15, 17 – 20. paratype (3) 16. 12, head, right half, tergal view. 13, right antenna, tergal view. 14, collum segment, median and left part, sternal view. 15, tergite VI, posteriomedian part. 16, genital papillae and seta on coca of leg 2, anterior view. 17, seta on coxa of leg 9. 18, tarsus of leg 9. 19, pygidium, posteriomedian and left posterior part, sternal view. 20, anal plate, lateral view. Pubescence only partly drawn in 18. Scale a: 17, 18; b: 12, 14 – 16; c: 13; d: 19, 20.