Decappauropus ungulatus, Scheller, 2009

Scheller, Ulf, 2009, New species of Pauropoda (Myriapoda) from Tasmanian temperate rainforests, Memoirs of Museum Victoria 66 (2), pp. 289-329 : 299-301

Decappauropus ungulatus sp. nov.

( Figs. 51–61 )

Material Examined. Holotype. Ad. 9 (female), Rivaux Creek , Loc. 16, (43°10'S, 146°38.6'E), litter, 20.xii.1988 ( PG).

Diagnosis. A single adult specimen is available but the singular shape of the anal plate in combination with the unusual shape of the antennal setae, the very small collum process and appendages and the arrangement and shape of the pubescence on the bothriotricha,make it well defined.It has some similarity with D. fibratus Scheller from Sri Lanka ( Scheller 1970), but the T 3 and the anal plate are dissimilar (the former with distal swelling in D. fibratus , not in D. ungulatus ; the appendages of the anal plate short, cylindrical and glabrous in D. fibratus , distinctly longer, clavate and pubescent in D. ungulatus ).

Description. Length.- 0.66 mm.

Head.-Tergal setae annulate, blunt, submedian ones somewhat clavate, lateral ones cylindrical. Relative lengths of setae, 1st row: a 1 =10, a 2 =13; 2nd row: a 1 =8, a 2 =20, a 3 =15; 3rd row: a 1 =12, a 2 =20; 4th row: a 1 =a 3 =17, a 2 =26, a 4 =19: lateral group setae: l 1 =30, l 2 = l 3 =27. The ratio a 1 /a 1 -a 1 in 1st row 1.0, 2nd row 0.5, 3rd row 0.9, 4th row 1.7. Temporal organs oval in tergal view, their length 1.1 times as long as their distance apart; small aperture outside posterior margin anterior of l 1. Head cuticle and temporal organs glabrous.

Antennae.-Segment 4 with 4 annulate setae: p, p' and p' ' somewhat clavate and distinctly annulate, r cylindrical; their relative lengths: p =100, p' =44, p'' =30, r =52. Neither p''', nor u. Tergal seta p 1.7 times as long as the length of tergal branch t. The latter somewhat fusiform, 2.1 times as long as its greatest diameter and as long as sternal branch s, that branch twice as long as its greatest diameter; anterodistal corner of s deeply truncate. Seta q subcylindrical, annulate, blunt, 1.2 times as long as s. Relative lengths of flagella (basal segments included) and basal segments: F 1 =100, bs 1 =7; F 2 =34, bs 2 =4; F 3 =?, bs 3 =7. The F 1 4.3 times as long as t, F 2 1.3 times as long as s. Distal calyces of F 1 subhemispherical, those of F 2 flattened. Distal part of flagella axes thickened, cylindrical in F 1, fusiform in F 2. Globulus g proportionally large, 1.5 times as long as wide; 10 bracts; capsule spherical; width of g 0.8 of the greatest diameter of t. Antennae glabrous.

Trunk. -Setae of collum segment cylindrical, annulate, blunt; rudiments of secondary branches not clear. Sublateral setae 2.3 times as long as submedian ones; sternite process very small and narrow; appendages subcylindrical with small flattened caps. Process and appendages glabrous.

Setae on tergites not studied.

Relative lengths of bothriotricha: T 1 =100, T 2 =108, T 3 =117, T 4 =127, T 5 =148; with simple, straight axes, somewhat thickened in T 3 only. Pubescence on proximal half of T 1 -T 4 simple, oblique, increasing in length outwards, more distally longer, branched, arranged in whorls; T 5 with short oblique pubescence of simple hairs.

Legs.-Setae on coxa and trochanter of leg 9 cylindrical, annulate, pointed; the former simple and the latter furcate with secondary branch somewhat shorter than primary branch, these setae of legs 1-8 simple. Tarsus of leg 9 distinctly tapering, 2.9 times as long as its greatest diameter. Setae cylindrical, annulate, blunt; proximal one 0.3 of the length of tarsus and 1.1 times as long as distal seta. The latter more densely annulate than the former. Cuticle of tarsus with short pubescence.

Pygidium. Tergum.-Posterior margin between st straight. Relative lengths of setae: a 1 =100, a 2 =83, a 3 =126, st =79, setae thin, cylindrical, striate, all but st directed posteriorly, pointed; st blunt, pointing inwards; a 1 curved outwards and somewhat pointing outwards, a 2 and a 3 curved inwards. Distance a 1 -a 1 0.8 of the length of a 1; distance a 1 -a 2 1.3 times as long as distance a 2 -a 3; distance st-st 1.6 times as long as st and 1.5 times as long as distance a

1

-a

1

. Cuticle glabrous.

Sternum.-Posterior margin between b 1 with deep broadly V-shaped indentation. Relative lengths of setae (a 1 =100): b 1 =?, b

2

=125. The b

2

as pygidial a

3

, 1.9 times as long as distance b 1 -b 2. Anal plate 2.4 times as long as broad with concave lateral margins and decreasing in width in distal 1/3, posterior margin with a deep median incision with parallel sides; two clavate pointing outwards appendages protrude posteriorly from sternal side; their length 0.3 of the length of plate; lateral margins and appendages with short pubescence.

Etymology.-From Latin ungula = hoof (shape of the anal plate).

Distribution in Tasmania. Probably rare, distribution outside the type locality unknown.

Figures

Figs. 51–61. Decapauropus ungulatus sp.nov., holotype: 51, head, median and right part, tergal view; 52, temporal organ, posterolateral part, lateral view; 53, left antenna, sternal view; 54, collum segment, median and left part, sternal view; 55, T; 56, T; 57, seta on coxa of 9th pair of 1 3 legs; 58, seta on trochanter of 9th pair of legs; 59, tarsus of 9th pair of legs; 60, pygidium, posterior and left part, sternal view; 61, anal plate, lateral view. Scale line a for figures 55, 56; b for figures 51, 52, 54, 57–59; c for figures 60, 61; d: 53.