Allopauropus Silvestri, 1902

Scheller, Ulf, 2013, Three new species of Pauropoda (Myriapoda) from Brazil with description of a new genus in Diplopauropodidae, Adelphopauropus, Zootaxa 3664 (1), pp. 69-77 : 69-71

Genus Allopauropus Silvestri, 1902

Allopauropus prolongus n. sp Figs 1 –8

Type locality. Brazil, Amazonas, 10 km from Carauari (4°52´56´´S, 66°03´45´´W), topsoil sample in Mardiocca vegetation.

Type specimen. Holotype: subad. 8(Ƥ), 1982, leg. A. Sortwell. – 1 specimen.

Diagnosis. The pygidial characters of the new species are typical for Allopauropus (pygidial sternum with setae b 1, b 2 and b 3, two setae, d 1 and d 2, in the subadult stage) but the sternal antennal branch is distinctly truncated anteriorly and more like those found in e.g. Decapauropus . Because the shape of the anal plate and the pygidial setae a 1 and st are also not easily referred to other species in Allopauropus the relationships of the species are difficult to trace.

Derivation of name. From the Latin prolongus = elongated, referring to the shape of the anal plate.

Description. Length. 1.07 mm.

Head (Fig. 1). Tergal setae subcylindrical striate-pubescent, lateral ones pointed. Relative lengths of setae, 1st row: a 1=10, a 2=12; 2nd row: a 1=10, a 2=20, a 3=14; 3rd row: a 1=9, a 2=10; 4th row: a 1≈ a 2≈10, a 3=15, a 4=16; lateral group setae: l 1= l 2=12, l 3 not studied. Ratio a 1/ a 1– a 1 in 1st and 3rd rows 1.0, 2nd row 0.4, 4th row ≈1.6. Length of temporal organs 0.8 of shortest interdistance. Head cuticle slightly granulated.

FIGURES 1-8. Allopauropus prolongus n. sp., holotype, subad. 8(Ƥ). 1, head, right half, tergal view. 2, left antenna, sternal view. 3, posterior part of tergite V, median part and right corner. 4, T 3. 5, T 1. 6, tarsus of leg 8. 7, pygidium, posteriomedian and left parts, sternal view. 8, pygidial setae d 1 and d 2. Scale a: 4, 5; b: 3, 6, 8; c: 1, 2, 7.

Antennae (Fig. 2). Segment 4 with 6 setae, p″′ rudimentary, the others thin cylindrical striate blunt, their relative lengths: p =10, p ′=6, p ″=4, r =3, u =1. Tergal seta p 1.1 times as long as tergal branch t. The latter branch 3.5 times as long as its greatest diameter and 1.1 times as long as sternal branch s, that branch 2.5 times as long as its greatest diameter; anterodistal corner distinctly more truncate than posterodistal one. Seta q as p of 4th segment, 0.5 of the length of s. Relative lengths of flagella (basal segments included) and basal segments: F 1=100, bs 1=7; F 2=42, bs 2=6; F 3=87, bs 3=8. F 1 3.6 times as long as t, F 2 and F 3 1.7 and 3.5 times as long as s respectively. Distal calyces helmet-shaped; distal part of flagella axes not widened below calyces. Globulus g pyriform, 1.4 times as long as wide, 5 bracts with distinct oblique pubescence, capsule subhemispherical on proportionately long stalk; width of g 0.8 of the greatest diameter of t. Segment 4 and antennal branches glabrous.

Trunk (Fig. 3). Collum segment studied only partly. Sublateral seta furcate, main branch tapering, striate, similar in length and shape to submedian setae on the tergal side of the head, secondary branch rudimentary; process pointed.

Setae on anterior tergites as submedian head setae; more posteriorly somewhat lengthened, tapering and slightly curved; 4+4 setae on tergite 1, 6+6 on II–IV, 6+4 on V (Fig. 3). Tergites with short dense pubescence of thin hairs.

Bothriotricha (Figs 4, 5). Relative lengths: T 1=100, T 2=102, T 3=109, T 5=202; all with thin simple straight axes, thickest in T 3 (Fig. 4), pubescence hairs short, simple, oblique except on distal third of T 1 (Fig. 5) and T 2, there short erect branched hairs.

Legs (Fig. 6). Setae on coxa and trochanter of all legs simple, cylindrical. Tarsus of leg 8 (Fig. 6) only slightly tapering, 3.8 times as long as its greatest diameter. Proximal seta pointed, with oblique pubescence, distal seta subcylindrical, densely striate; proximal seta almost 0.4 of the length of tarsus and 2.9 times as long as distal seta. Cuticle of tarsus with short pubescence.

Pygidium (Figs 7, 8). Tergum. Posterior margin slightly indented between setae st. Relative lengths of setae: a 1=10, a 2=60, a 3=160, st =20; a 1 and st directed posteriorly, straight, both with erect pubescence, a 2 and a 3 directed posteriorly-outwards, both also curved inwards and with oblique pubescence, a 1 short clavate, st lanceolate. Length of setae a 1 0.2 of distance a 1- a 1; distance a 1- a 2 ≈10 times as long as distance a 2 –a 3; distance st-st 2.4 times as long as st and very little longer than distance a 1 –a 1. Cuticle glabrous,

Sternum. Distinct triangular lateral lobes, posteriorly rounded; between them and below anal plate two large semi-circular lobes. Relative lengths of setae (pygidial a 1 =10): b 1=77, b 2=54, b 3=13; setae thin cylindrical tapering, b 1 with indistinct striation in apical half, b 2 and b 3 with oblique pubescence, b 1 and b 2 curved inward and converging; b 3 straight; b 1 1.1 times as long as interdistance; b 2 as long as distance b 1 –b 2, b 3 0.2 of interdistance.

Anal plate (Fig. 7) longish subrectangular, lateral margins straight, posterodistal corners obliquely truncate; two narrow-sublanceolate appendages protruding backwards from posteriolateral truncations, their length 0.8 of the length of the plate.

Pygidial setae d 1 and d 2 well developed (Fig. 8).