Decapauropus attenuatus, Scheller, 2009

Scheller, Ulf, 2009, New species of Pauropoda (Myriapoda) from Tasmanian temperate rainforests, Memoirs of Museum Victoria 66 (2), pp. 289-329 : 296-299

Decapauropus attenuatus sp.nov.

( Figs. 39–50 )

Material Examined. Holotype. Ad. 9 (female), Bruny Island , Mount Mangana, Loc. 12, (43°22.1 ' S, 147°17.0'E), litter, 4.iv.1989 ( PG).

Paratypes. Locality as for holotype, in moss, 3 ad. 9 (2 male, 1 female), 1 subad. 8 (female), 9.iv.1989 ( JD) .

Other material. 10 specimens. Loc. 4, moss on log, 1 ad. 9 (female), 1 subad. 8 (female), 18.xi.1989 ( HM). Loc. 7, rotten log , 1 ad. 9 (female), 17.v.1989 ( JD). Loc. 11, moss on dead log , 1 ad. 9 (female), 21.iii.1989 ( JD). Loc. 12, moss on log , 1 juv. 3, 9.xi.1989, and leaf litter, 2 ad. 9 (female), 9.iv.1989, and moss on dead log, 2 ad. 9 (male, female), 9.iv.1989 ( PG), and in moss , 1 ad. 9 (female), 9.iv.1989 ( JD) .

Diagnosis. The affinities are difficult to trace but the species is well delineated by the combination of the following characters: rather long tergal head setae, anterior ones clavate; the T 3 with proximal 2/3 fusiform but very thin distally; the shape of the anal plate with concave lateral margins, distal incision and two long appendages which are curved inwards.

Description. Length.- (0.56-)0.63(-0.74) mm.

Head.-Most tergal setae of medium length, some posterolateral rather long, anterior and submedian ones somewhat clavate, others cylindrical, striate, blunt but lateral group setae pointed. Relative lengths of setae, 1st row: a 1 =10, a 2 =10(-12); 2nd row: a 1 =(11-)13, a 2 =(14-)16(-18), a 3 =(13-)16; 3rd row: a 1 =11(-12), a 2 =13(-15); 4th row: a 1 =(14-)15(-16), a 2 =19(-23), a 3 =(17-)19, a 4 =(13-)15(-16); lateral group setae: l 1 =(22-)25, l 2 =13(-18), l 3 =?(22). The ratio a 1 /a 1 -a 1 in 1st row 1.0(-1.1), 2nd row (0.6-)0.7, 3rd row 1.0(-1.2) and 4th row 1.4(-1.7). Length of temporal organs 0.7(-0.9) of their shortest distance apart; small aperture in posterior part anterior of l 1. Head cuticle somewhat granular, temporal organs glabrous.

Antennae.-Segment 4 with five thin cylindrical striate setae; their relative lengths: p =100, p' = (71-)76(-78), p'' =(22-)24(-28), p''' =11(-18), r=24(-27), u absent. Tergal seta p (1.4-)1.5(-1.6) times as long as tergal branch t. The latter fusiform, 2.8(-3.6) times as long as its greatest diameter and as long as sternal branch s, that branch (2.0-)2.2(-2.6) times as long as its greatest diameter; anterodistal corner of s truncate. Seta q cylindrical, striate, as long as (-1.2 times as long as) s. Antennal flagella often broken; relative lengths (basal segments included) and basal segments: F 1 =100, bs 1 =(6-)8; F 2 =(78-81), bs 2 =7; F 3 =(80-92), bs 3 =(6-)8. The F 1 2.8(-3.4) times as long as t, F 2 and F 3?(1.8-2.7) and (2.0-2.9) times as long as s respectively. (Antennal flagella broken in holotype). Distal calyces somewhat flattened; distal part of flagellar axes fusiform. Globulus g (1.2-)1.3 times as long as wide; nine bracts, capsule spherical; width of g 0.6(-0.8) of the greatest diameter of t. Antennae with short pubescence.

Trunk.-Setae of collum segment somewhat clavate, annulate, blunt, furcate, but with rudimentary glabrous blunt secondary branches; sublateral ones (1.8-)2.1(-2.6) times as long as submedian ones; sternite process triangular with small anterior incision; appendages obliquely barrel-shaped with flattened caps; process and basal segment of appendages with delicate pubescence.

Setae on anterior tergites cylindrical, annulate, blunt; on posterior tergites somewhat shorter, subcylindrical, tapering, with oblique pubescence. 4+4 setae on tergite I, 6+6 on II–IV, 6+4 on V, 4+2 on VI. Submedian posterior setae on VI (0.6–)0.7 of their distance apart and (0.8-)0.9 of the length of pygidial setae a 1. Tergites with short minute pubescence.

Relative lengths of bothriotricha: T 1 =100, T 2 =95(-101), T 3 =(97-)112(-113), T 4 =(107-)108(-130), T 5 =(165-)167(-187), with simple straight axes, in all but T 3 very thin; the latter with proximal 2/3 thickened, fusiform, tapering into a thin distal 1/3. Pubescence hairs on T 1, T 2 and T 4 similar, hairs thin, straight, rather sparse, on proximal halves short and oblique, erect and longer distally. The T 5 with very short oblique pubescence.

Genital papillae (paratypes) subcylindrical, glabrous, 2.2(-2.3) times as long as their greatest diameter; seta 0.3(-0.4) of the length of organ.

Legs.-Setae on coxa and trochanter of leg 9 similar, furcate; branches striate, blunt, subequal in length, primary branch somewhat clavate, secondary branch cylindrical, these seta more anteriorly with blunt glabrous rudimentary secondary branches; setae on trochanter somewhat widened distally, those on coxa clavate. Coxal seta on leg 2 in male clavate too. Tarsus of leg 9 slender, 3.8(-4.3) times as long as its greatest diameter. Setae thin, proximal one tapering pointed, with oblique pubescence; distal one cylindrical, blunt, striate; proximal seta (0.4-)0.5 of the length of tarsus and (2.2-)2.5(-2.6) times as long as distal seta. Cuticle of tarsus with distinct pubescence.

Pygidium. Tergum.-Posterior margin between st rounded and with shallow median indentation. Relative lengths of setae: a 1 =100, a 2 =(100-)106(-113), a 3 =(135-)137(-160), st =(60-)62(-80), setae thin, tapering, pointed, indistinctly striate, somewhat curved inwards, a 1 and a 3 with short pubescence distally; a 1 directed posteriorly, a 2 and st pointing inwards, a 3 somewhat pointing outwards. Distance a 1 -a 1 0.9(-1.2) times as long as a 1; distance a 1 -a 2 (1.5-)1.8 times as long as distance a 2 -a 3; distance st-st (2.1-)2.4 times as long as st and (1.4-)1.6(-1.7) times as long as distance a 1 -a 1. Cuticle glabrous.

Sternum.-Posterior margin between b 1 with a broad shallow indentation. Relative lengths of setae (a 1 =100): b 1 =(343-)362(-404), b 2 =(80-)94(-100), setae thin, b 1 subcylindrical, tapering, striate, blunt; b 2 tapering, pointed, striate. The b 1 (1.3-)1.4(-1.5) times as long as their distance apart; b 2 (0.8-)0.9 of distance b 1 -b 2. Anal plate as long as (-1.2 times as long as) broad, granular, broadest anteriorly, with somewhat indented lateral margins and posterior margin divided into two rounded lobes by a broadly V-shaped indentation; from posterosternal margin of the lobes protrude backwards two pointing outwards appendages slightly curving inwards, being 1.3(-1.6) times as long as the length of plate.

Stage subad. 8. The setae d 2 of pygidial tergum thin, straight, cylindrical, striate, 0.4 of the length of pygidial setae a 1; d 2 -d 2 about 10 times longer than d 2.

Etymology.-From Latin attenuatus = drawn out, thin (T 3; setae of the pygidial tergum).

Distribution in Tasmania. Seems to be a rare species collected in the eastern parts only.

Figures

Figs. 39–43. Decapauropus attenuatus sp.n., holotype: 39, head, median and right part, tergal view; 40, right temporal organ, posterior part, lateral view; 41, left antenna, tergal view; 42, collum segment, median and left part, sternal view; 43, tergite VI, posterior part. Scale line a for figures 39, 40, 42; b for figures 41, 43.

Figs. 44–50. Decapauropus attenuatus sp.nov., holotype 44–45, 47–50; paratype 46: 44, T; 45, T; 46, genital papillae and seta on coxa of 2nd 1 3 pair of legs; 47, seta on trochanter of 9th pair of legs; 48, tarsus of 9th pair of legs; 49, pygidium, posteromedian and left part, sternal view; 50, anal plate, lateral view. Scale line a for figures 44–48; b for figures 49, 50.