Decapauropus anatonus, Scheller, Ulf, 2011

Scheller, Ulf, 2011, New records of Pauropoda (Myriapoda) from north-western Thailand, International Journal of Myriapodology 4, pp. 51-77 : 61-62

Decapauropus anatonus sp. n. Figs 36-45

Material.

Holotype ad. 9(♂), Thailand, Chiang Mai province, Doi Inthanon, below the top, primary rain forest, litter, alt. 2400 m, 1991.vii.4, loc. CM-210.

Etymology.

From the Latin anatonus, extending upward (referring to the shape of the distal part of the bracts of the antennal globulus g).

Diagnosis.

There are some species with resembling though not identical anal plates but Decapauropus anatonus sp. n. is well defined by the shape of the antennal globulus g with slender stalk and distal parts of the bract turned upward, this also combined with a distal swelling on the bothriotricha T3. At present its relationships are not possible to trace.

Description.

Length. 0.43 mm. Head (Fig. 36). Setae on the tergal side subcylindrical striate. Relative lengths of setae, 1st row: a1=a2=10; 2nd row: a1=10, a2=14, a3=20; 3rd row: a1=11, a2=?; 4th row: a1=10, a2=17, a3=24, a4=13; lateral group setae not studied. Ratio a1/a1-a1 in 1st row 1.4, 2nd row 0.5, 3rd row 1.3, 4th row 1.2. Temporal organs in tergal view ovoid, length 0.8 of their shortest interdistance. Head cuticle glabrous.

Antennae (Fig. 37). Segment 4 with at least three cylindrical striate setae; their relative lengths: p=10, p’ =r=7. Tergal seta p 1.5 times as long as tergal branch t. The latter fusiform, twice longer than its greatest diameter and 0.7 of the length of sternal branchs,that branch 1.8 times as long as its greatest diameter; anterodistal corner distinctly truncate. Seta q cylindrical striate, 0.6 of the length of s. Relative lengths of flagella not available for study; F1 long, distal calyces flattened, distal part of flagella axes inconsiderably widened below calyx. F1 6.2 times as long as t. Globulus g pyriform, proportionally long, 1.7 times as long as the greatest diameter, stalk as long as globulus, bracts thin, turned upward distally, ≈10 bracts, capsule with flattened bottom, width of g 0.8 of the greatest diameter of t. Antennae glabrous.

Trunk (Figs 38, 39). Setae of collum segment (Fig. 38) simple cylindrical striate, sublateral setae 1.3 times as long as submedian setae; sternal process blunt anteriorly, lateral margins concave; caps low, roundly conical. Process and appendages glabrous.

Tergite I incompletely divided transversally; 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. 39) 0.5 of interdistance and 0.8 of the length of pygidial setae a1.

Genital papillae (Fig. 40). Conical, 1.9 times as long as the greatest diameter, seta thin, 0.5 of the length of papilla.

Bothriotricha (Fig. 41). Relative lengths: T1=100, T2=?, T3=112, T4=140, T5=157; axes simple straight, very thin and with faint pubescence only distally, T3 (Fig. 41) strongest, with narrowly ovoid end-swelling and with distinct oblique pubescence on swelling and just below it.

Legs (Figs 42, 43). Setae on coxa and trochanter (Fig. 42) of legs 1-9 simple cylindrical striate. Tarsus of leg 9 (Fig. 43) tapering, 3.6 times as long as its greatest dia meter; proximal seta very thin tapering, distal seta cylindrical blunt striate, proximal one 0.2 of the length of tarsus and 1.2 times as long as the length of distal seta. Cuticle of tarsus glabrous.

Pygidium (Fig. 44, 45). Tergum. Posterior margin rounded and with shallow lobe between st. Relative lengths of setae: a1=10, a2=8, a3=17, st=6; setae thin, directed posteriorly, a-setae tapering pointed, curved inward, st cylindrical blunt. Distance a1-a1 0.6 of the length of a1, distance a1-a2 1.8 times as long as a2-a3; distance st-st 1.8 times as long st and twice longer than distance a1-a1.

Sternum. Posterior margin rounded and with very small posterior lobe below anal plate. Relative lengths of setae (pygidial a1=10): b1=32, b2=8, setae thin tapering, striate, b1 1.3 times as long as interdistance, b2 0.5 of distance b1-b2.

Anal plate directed posteriorly, as long as broad, lateral margins convex, posterior margin with shallow incision, posterodistal corners lengthened into two clavate appendages, these 0.7 of the length of plate; plate glabrous.