Stylopauropoides quadripartitus, Scheller, 2009

Scheller, Ulf, 2009, New species of Pauropoda (Myriapoda) from Tasmanian temperate rainforests, Memoirs of Museum Victoria 66 (2), pp. 289-329 : 314-316

Stylopauropoides quadripartitus sp.nov.

( Figs.128–141 )

Material Examined. Holotype. Ad. 9 (female), Savage River Pipeline Road , Loc. 1, (41°18.5'S, 145°16.3'E), litter, 21.iv.1989 ( PG).

Paratypes. Same data as holotype, 1 ad. 9 (female), 1 subad. 8 (female). Sandspit River, Loc. 8, (42°42.1'S, 147°51.5'E), in leaf litter, 3 ad. 9 (2 male, 1 female), 22.v.1989 ( PG) .

Other material. 60 specimens. Loc. 1, in moss on ground, 1 ad. 9 (female), 21.iv.1989 ( HM). Loc. 3, soil core , 1 ad. 9 (female), 9.iii.1989 ( PG). Loc. 4, in moss on ground , 1 ad. 9 (female), 17.xi.1989 ( RC), and in litter , 1 juv. 5, 18.xi.1989 ( HM), and in soil core , 2 ad. 9 (male), 2 subad. 8 (female), 3-8.xi.1989 ( PG). Loc. 6, suction , 1 juv. 6, 28.xi.1989 ( RC). Loc. 7, tree fern crown , 4 ad. 9 (female), 1 juv. 5, 17.v.1989 ( HM), and in leaf litter , 1 ad. 9 (female), 12.v.1989 ( PG). Loc. 8, in soil core , 1 ad. 9 (female), 22.v.1989 ( PG). Loc. 9, in soil core , 1 ad. 9 (female), 20.x.1989 ( RC), and in litter , 1 ad. 9 (female), 18.xi.1988 ( PG). Loc. 11, in moss on fallen log , 2 ad. 9 (male, female), 1 subad. 8 (female), 1 juv. 6, 21.iii.1989 ( JD). Loc. 12, litter , 12 ad. 9 (4 male, 8 female), 3 subad. 8 (1 male, 2 female), 9.iv.1989 ( PG). Loc. 13, litter , 14 ad. 9 (6 male, 8 female), 4 subad. 8 (1 male, 3 female), 27.ii.1989 ( SS). Loc. 17, in non-myrtle litter , 1 ad. 9 (male), 8.iii.1989 ( PG). Loc. 19, leaf litter , 2 ad. 9 (female), 1 subad. 8 (male), 1 juv. 6, 20.vi.1989 ( PG) .

Diagnosis. Stylopauropoides quadripartitus is a long-legged species which is clearly distinguished from its congeners by the shape of its two-part anal plate: each half divided into two pointed branches, one lateral and the other posterior. It may be closest to S. hirtus (Remy) from New Zealand ( Remy 1952b, 1956a) but, in that species, the posterior branches are cut squarely and have short cylindrical appendages and the pygidial setae a 1 do not reach more than 0.4–0.5 of the length of the a 2, not 0.7–0.9.

Description. Length.-(0.74-)1.25(-1.28) mm.

Head.-Submedian setae on the tergal side of medium length, somewhat clavate, striate; sublateral and lateral setae fairly long, cylindrical, densely striate. Relative lengths of setae, 1st row: a 1 =10, a 2 =(10-)11; 2nd row: a 1 =12(-14), a 2 =14(-15), a 3 =15(-16); 3rd row: a 1 =11(-13), a 2 =(12-)14; 4th row: a 1 =14(-15), a 2 =a 3 =(18-)19, a 4 =13(-14); lateral group setae: l 1 =26(-27), l 2 =(19-)24, l 3 =(26-)29. The ratio a 1 /a 1 -a 1 in 1st row 1.0(-1.2), 2nd row 0.6(-0.7), 3rd row 0.7(-1.0) and 4th row 1.1(-1.3). Temporal organs in tergal view ovoid, their length 0.7(-0.8) of their shortest distance apart. Just outside the posterior margin on a level with l 1, a small aperture in the cuticle and inside the posterior margin, in a depression, a clavate somewhat curved exterior vesicle. The latter almost 0.2 of the length of temporal organ and attached to it with its narrow anterior end. Head cuticle with indistinct transverse suture between 2nd and 3rd rows of setae; head cuticle with delicate granules, temporal organs with short erect pubescence.

Antennae.-Segment 4 with six subcylindrical annulate-striate setae; their relative lengths: p =100, p' =(67-)72(-79), p'' =(44-)56, p''' =(21-)28, r =28(-35), u =(9-)10. Tergal seta p (0.8-)0.9(-1.1) times as long as tergal branch t. The latter fusiform, (2.9-)3.2(-3.4) times as long as its greatest diameter and as long as (-1.1) times as long as sternal branch s, that branch (2.1-)2.2(-2.3) times as long as its greatest diameter; posterodistal and anterodistal corners equally truncate. Seta q subcylindrical, tapering, annulate-striate, pointed, 0.7(-0.9) times the length of s. Relative lengths of flagella (basal segments included) and basal segments: F 1 =100, bs 1 =(6-)8(-9); F 2 =(71-)74(-83), bs 2 =(9-)10(-11); F 3 =79(-87), bs 3 =(9-)10(-11). The F 1 (2.6-)3.0 times as long as t, F 2 and F 3 (1.9-)2.2(-2.5) and (2.2-)2.4(-2.7) times as long as s respectively. Distal calyces hemispherical; distal part of flagella axes widened only between calyx and the distal lamella. Globulus g (1.2-)1.5 times as long as wide; (12-)13(-14) bracts, capsule subspherical; width of g (0.7-)0.8 of the greatest diameter of t. Rudimentary globulus on posterotergal side of 3rd segment. Antennae glabrous.

Trunk.-Setae of collum segment furcate; primary branch folioform with short oblique pubescence, secondary branch rudimentary, cylindrical, glabrous. Sublateral setae as long as (-1.2 times as long as) submedian ones; sternite process short and broad, anterior part narrow and with very small incision; appendages low and wide with flat caps; process with short lateral pubescence, appendages with delicate pubescence.

Setae on anterior tergites as lateral setae on the head, tapering posteriorly and with short, oblique pubescence; setae on posterior tergites not longer than those on anterior tergites; 4+4 setae on tergite I, 6+6 on II-V, 4+2 on VI. Submedian posterior setae on VI 0.4(-0.5) of their distance apart and (1.1-)1.2(-1.4) times as long as pygidial setae a 1.

Relative lengths of bothriotricha: T 1 =100, T 2 =(103-)?(-110), T 3 =95(-108), T 4 =116(-127), T 5 =149 and 180(-196); axes simple, thin, straight except proximal half of T 3 being moderately thickened. Pubescence hairs on T 5 very short, on proximal halves of T 1 -T 4 stronger, oblique, increasing in length outwards and on distal 1/3 long, ramose, whorled, most distally erect, for the rest directed obliquely downwards.

Genital papillae (paratype) short, conical, rounded distally, about as long as wide, glabrous; seta very thin, 0.4 of the length of the organ.

Legs.-Setae on coxa and trochanter of leg 9 furcate, densely pubescent, main branch leaf-shaped, broadest in the middle, secondary branch clavate, protruding from the middle of the primary one and reaching (0.6-)0.7 of the length of primary branch. These setae on more anterior legs with proportionately broader main branch and rudimentary glabrous secondary branch. Tarsus of leg 9 (4.4-)4.5(-4.7) times as long as its greatest diameter. Proximal seta tapering, pointed, with very short oblique pubescence; distal seta subcylindrical, annnulate, blunt. Proximal seta 0.4 of the length of tarsus and (2.9-)3.0 times as long as distal seta. Cuticle of tarsus with short pubescence.

Pygidium. Tergum.-Posterior margin between st straight. Relative lengths of setae: a 1 =100, a 2 =(112-)140(-148), a 3 =181(-188), st =(38-)52; setae curved inwards, tapering, pointed, very shortly pubescent; a 1 and a 2 pointing inwards. Distance a 1 -a 1 (2.3-)2.7 times as long as a 1; distance a 1 -a 2 as long as (-1.4) times as long as distance a 2 -a 3; distance st-st (3.6-)4.0 times as long as st and (0.6-)0.7 of distance a 1 -a 1.

Sternum.-Posterior margin above b 1 with a broad triangular lobe. Relative lengths of setae (a 1 =100): b 1 =(204-)214 and 236; setae thin, shortly pubescent, tapering, 1.3 and 1.4(-1.5) times as long as their distance apart. Anal plate directed obliquely upwards, 1.3(-1.5) times as broad as long; divided longitudinally into two branches each in turn divided into two branches by a posterolateral incision; the secondary branches tapering, pointed, the posterior ones longest; lateral branches pointing outwards, posterior ones pointing inwards.

Stage subad. 8. Pygidial setae d 1 and d 2 thin pointed, the former 0.5 of their distance apart, d 2 0.6 of distance d 1 -d 2.

Etymology.-From Latin quadripartitus = four-parted (anal plate).

Distribution in Tasmania. Probably one of the most widespread pauropods of the Tasmanian rainforests as it occurs in all major regions and has been collected at nine of the 12 main collecting sites and in three of the additional ones.

Figures

Figs. 128–141. Stylopauropoides quadripartitus sp.nov., holotype 128–135, 137–141; paratype 136: 128, head, median and right part, tergal view; 129, temporal organ, posterior part with pistil, lateral view; 130, right antenna, tergal view; 131, 3rd antennal segment, tergal view; 132, collum segment, median and left part, sternal view; 133, tergite VI, posterior part; 134, T; 135, T; 136, genital papillae and seta on coxa of 2nd pair of 1 3 legs, anterior view; 137, seta on coxa of 9th pair of legs; 138, seta on trochanter of 9th pair of legs; 139, tarsus of 9th pair of legs; 140, pygidium, median and left part, sternal view; 141, anal plate, lateral view. Scale line a for figures 133–136; b for figures 128, 129, 132, 137–139; c for figures 130, 131, 140, 141.