Decapauropus capillaris, Scheller, Ulf, 2011

Scheller, Ulf, 2011, New records of Pauropoda (Myriapoda) from north-western Thailand, International Journal of Myriapodology 4, pp. 51-77 : 55-57

Decapauropus capillaris sp. n. Figs 10-19

Material.

Holotype ad. 9(♂), Thailand, Chiang Mai province, Doi Inthanon, Mae Chaem road, secondary dry forest, litter, alt. 1150 m, 1991.vi.30, loc. CM-080. - Paratypes: 3 ad. 9 (2♀, 1♂), same data as holotype. - 4 specimens.

Etymology.

From the Latin capillaris, slender as a hair (referring to the thin setae).

Diagnosis.

Decapauropus capillaris shows striking resemblances to Decapauropus virgininsularis Scheller ( Scheller 1990) from the U.S. Virgin Islands. They can be distinguished by the shape of the tergal antennal branch, 3.4-3.5 times as long as its greatest diameter in Decapauropus capillaris , not 4.9-5.3, the setae of the collum segment, both of the same shape, not sublateral seta much longer and thicker than submedian one, the tarsus of the last pair of legs, only somewhat tapering, not strongly tapering and very slender distally, the size of the st, rudimentary, not well developed, and the shape of the lateral margins of the anal plate, convex, not concave.

Description.

Length. (0.50-)0.52(-0.65) mm. Head (Fig. 10). Setae on the tergal side thin striate. Relative lengths of setae (holotype only), 1st row: a1=a2=10; 2nd row: a1=11, a2=13, a3=15; 3rd row: a1=?, a2=11; 4th row: a1=?, a2=14, a3=16, a4=?; lateral group setae, l1=19, l2=17, l3=10. Ratio a1/a1-a1 in 1st row 1.0, 2nd row 0.8, 3rd and 4th row?. Temporal organs in tergal view broadest in posterior part, length 0.9 of their shortest distance apart. Pore not ascertained. Head cuticle glabrous.

Antennae (Fig. 11). Segment 4 with five setae, all thin cylindrical striate; their relative lengths: p=10, p’ =44, p’’ =11, p’’’ =5, r=39. Tergal seta p 1.2 times as long as the length of tergal branch t. The latter fusiform, (3.4-)3.5 times as long as its greatest diameter and 1.3 times as long as the length of sternal branchs,that branch 2.1 times as long as its greatest diameter; anterodistal corner distinctly truncate. Seta q thin cylindrical striate, 1.3 times as long as the length of s. Relative lengths of flagella (basal segments included) and basal segments: F1=100, bs1=5; F2=?, bs2=4; F3=76, bs3=5. F1 3.7 times as long as t, F3 3.0 times as long as s. Distal calyces small rounded, distal part of flagella axes not widened below calyces. Globulus g subspherical, 1.2 times as long as wide, 8 bracts, capsule with flattened bottom; width of g 0.8 of the greatest diameter of t. Antennae glabrous.

Trunk (Figs 12, 13). Setae of collum segment (Fig. 12) furcate, main branch cylindrical blunt striate, secondary branch rudimentary, sublateral setae 1.7 times as long as submedian setae; sternite process triangular, pointed anteriorly; appendages tapering distally. Process and appendages glabrous.

Setae on tergites as setae on the head, 4+4 setae on tergite I, 6+6 on II-V, 4+2 on VI. Submedian posterior setae on VI (Fig. 13) long tapering pointed, 1.4 times as long as interdistance.

Genital papillae (Fig. 14). Conical, 2.0 times as long as the greatest diameter, seta thin, 0.4 of the length of papilla.

Bothriotricha (Fig. 15). Relative lengths (holotype only): T1=100, T2=152, T3=105, T4=123, T5=131; axes simple straight, very thin and with short pubescence, erect distally; T3 only (Fig. 15) stronger, fusiformly thickened in proximal ¾ and with distinct oblique pubescence.

Legs (Figs 16, 17). Setae on coxa and trochanter (Fig. 16) 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 (paratype male). Tarsus of leg 9 (Fig. 17) tapering, 3.5(-3.6) times as long as its greatest diameter; setae thin, proximal one tapering pointed, distal one subcylindrical blunt, faintly striate, proximal seta (0.3-)0.4 of the length of tarsus and (3.4-)3.5 times as long as distal seta. Cuticle of tarsus glabrous.

Pygidium (Figs 18, 19). Tergum. Posterior margin rounded but with small posterior lobe between st. Setae a1 broken or rudimentary, relative lengths of setae: a2=10, a3=18, st rudimentary; setae directed posteriorly, a2 and a3 long thin tapering glabrous, somewhat curved inward. Distance a1-a2 three times longer than distance a2-a3; distance st-st ≈20 times as long as st and 0.4 of distance a1-a1.

Sternum. Posterior margin with distinct indentation and broadly triangular lobe below anal plate. Relative lengths of setae (pygidial a2=10): b1=7, b2=3, setae thin tapering, b1 indistinctly striate in distal half, as long as interdistance, b2 0.7(-0.8) of distance b1-b2.

Anal plate somewhat turned up, narrowest anteriorly, linguiform, lateral margins a little convex, on underside of rounded distal part two very short cylindrical blunt appendages protruding backwards-downwards; plate glabrous.