Decapauropus prolixus, Scheller, Ulf, 2011

Scheller, Ulf, 2011, New records of Pauropoda (Myriapoda) from north-western Thailand, International Journal of Myriapodology 4, pp. 51-77 : 52-55

Decapauropus prolixus sp. n. Figs 1-9

Material.

Holotype ad. 9(♂), Thailand, Chiang Mai province, Doi Inthanon, Mae Chaem road, secondary dry forest, litter, alt. 1150 m, 1991.vii.4, loc. CM-096. - 1 specimen.

Etymology.

From the Latin prolictus, stretched out long (referring to the posterolateral appendages of the anal plate).

Diagnosis.

Decapauropus prolixus may be close to Decapauropus bispinus Scheller (2009) from Sulawesi in Indonesia but can readily be distinguished from it by the shape of the temporal organs of the head, in tergal view small and longish in Decapauropus prolixus , large in Decapauropus bispinus , the antennal globulus g, pyriform, not spherical, the shape of the pygidial st, long, thin, cylindrical, not short, globular, and the lateral margins of the anal plate, parallel, not distinctly convex.

Description.

Length. 0.48 mm. Head (Fig. 1). Setae on the tergal side subcylindrical striate. Relative lengths of setae, 1st row: a1=10, a2=12; 2nd row: a1=14, a2=15, a3=17; 3rd row: a1=12, a2=15; 4th row: a1=14, a2=15, a3=18, a4=11; lateral group setae, l1=18, l2≈17, l3=?. Ratio a1/a1-a1 in 1st row 0.9, 2nd row 0.5, 3rd row 0.8, 4th row 1.5. Temporal organs small, in tergal view ovoid, as long as their shortest distance apart. Head cuticle glabrous.

Antennae (Fig. 2). Segment 4 with 4 cylindrical striate setae; their relative lengths: p=10, p’ =8, p’’ =2, r=5. Tergal seta p 0.9 of the length of tergal branch t. The latter fusiform, 2.7 times as long as its greatest diameter and 1.1 times as long as the length of sternal branchs,that branch 1.7 times as long as its greatest diameter; anterodistal corner distinctly truncate. Seta q cylindrical striate, 0.7 of the length of s. Relative lengths of flagella (basal segments included) and basal segments: F1=100, bs1=7; F2=58, bs2=5; F3=91, bs3=5. F1 3.4 times as long as t, F2 and F3 2.1 and 3.3 times as long as s respectively. Distal calyces of F1 and F3 conical, those of F2 hemispherical, distal part of flagella axes inconsiderably widened below calyces. Globulus g proportionally large, pyriform, 1.5 times as long as wide, ≈10 bracts, capsule subspherical; width of g as long as the greatest diameter of t. Antennae glabrous.

Trunk (Figs 3, 4). Setae of collum segment (Fig. 3) simple cylindrical striate, sublateral setae 1.3 times as long as submedian setae; sternite process triangular, blunt anteriorly; appendages tapering distally, caps low. Process and appendages glabrous. Setae on tergites as setae on the head, 4+4 setae on tergite I and?4+2 on VI, interposed tergites not studied. Submedian posterior setae on VI (Fig. 4) 0.5 of interdistance and 0.6 of the length of pygidial setae a1.

Genital papillae (Fig. 5). Proximal 2/3 subcylindrical, distal part tapering into an subcylindrical top, papillae 2.1 times as long as the greatest diameter, seta thin, 0.3 of the length of papilla.

Bothriotricha (Fig. 6). Relative lengths: T1=T3=100, T2=108, T4=138, T5=196; axes simple straight, very thin and with faint pubescence only distally, T3 only (Fig. 6) stronger, fusiformly thickened in distal ¾ and with distinct oblique pubescence.

Legs (Figs 7, 8). Setae on coxa and trochanter (Fig. 7) of leg 9 furcate, branches cylindrical striate, secondary branch shorter than primary one. These setae more anteriorly with rudimentary secondary branches except in coxal setae of leg 2. Tarsus of leg 9 (Fig. 8) tapering, 3.5 times as long as its greatest diameter; proximal seta very thin tapering pointed, distal seta subcylindrical blunt striate, proximal one 0.3 of the length of tarsus and as long as the length of distal seta. Cuticle of tarsus glabrous.

Pygidium (Fig. 9). Tergum. Posterior margin between st straight. Relative lengths of setae: a1=10, a2=9, a3=19, st=6; setae directed posteriorly, a1 and a3 almost straight, a2 and st curved inwards, a1 striate distally. Distance a1-a1 0.9 of the length of a1, distance a1-a2 twice longer than distance a2-a3; distance st-st 1.3 times as long as st and as long as distance a1-a1.

Sternum. Posterior margin with low and broad bulge below base of anal plate. Relative lengths of setae (pygidial a1=10): b1=31, b2=10, setae thin tapering, b1 with short pubescence distally, 1.4 times as long as interdistance, b2 0.7 of distance b1-b2.

Anal plate directed posteriorly, lateral margins parallel, posterodistal corners lengthened into two long tapering and distally faintly striate appendages, these ≈1.6 times as long as the length of plate; posterior margin between appendages U-shaped and with two short tapering glabrous appendages protruding backwards from sternal margin, length of short appendages ≈ ¼ of the length of posterolateral appendages; plate glabrous.