A remarkable new genus and species of Hansenauropodidae (Myriapoda Pauropoda) from the seashore of Hainan Island, China Author Bu, Yun text Zootaxa 2020 2020-06-26 4803 2 373 380 journal article 10.11646/zootaxa.4803.2.8 1175-5326 3909216 ADAC0F5A-B734-4FED-976F-7387EBEC1FF7 Psammopauropus macrospinus new species Figures 3–26 Material examined : Holotype , male with 9 pairs of legs (slide no. HN-SY-PA2017054) ( SNHM ), China , Hainan Province , Sanya City , flotation of sand and debris from seashore of Sanya Bay , 18°18’N / 109°22’E , 20-X-2017 , coll. Yun Bu. Paratypes , 4 females , in alcohol, same locality data as holotype . Diagnosis . As for the genus. Description . Body slender, with short legs, holotype length 1.23 mm ( Figs. 11, 12 ). Head ( Figs. 3 , 13 ). Dorsal setae short, rudimentary and bud-shaped, medial and lateral setae cylindrical, striate. Relative lengths of setae, 1 st row: a 1 = 10, a 2 = 10; 2 nd row: a 1 = 10, a 2 = 43, a 3 = 40; 3 rd row: a 1 = 10, a 2 = 17; 4 th row: a 1 = 10, a 2 = 40, a 3 = 16, a 4 = 45; lateral group setae l 1 = 40, l 2 = 37, l 3 = 40; the ratio a 1 / a 1 – a 1 in 1 st row 0.6, 2 nd row 0.3, 3 rd row 0.4 and 4 th row 0.4. Temporal organs oval in dorsal view, their length 1.4 times as long as their shortest distance apart ( Fig. 13 ). Pistil present. Head cuticle faintly granular. Antennae ( Figs. 4 , 16 ). Antennal segments 1–3 with 2, 2, 3 short bud-shaped pubescent setae, respectively. Antennal segment 4 with four cylindrical setae; relative lengths of setae: p = 10, p ’ = 8, p ’’ = 5, r = 4; tergal seta p 1.5 times as long as tergal branch t ; the latter cylindrical, 1.6 times as long as its greatest diameter and 1.3 times as long as sternal branch s , which itself is 1.3 times as long as its greatest diameter. Seta q cylindrical, striate, 1.2 times as long as s . Relative lengths of flagella (base segments included) and base segments: F 1 = 100, bs 1 = 9; F 2 = 38, bs 2 = 6; F 3 =89, bs 3 = 8. F 1 6.5 times as long as t, F 2 and F 3 1.9 and 4.5 times as long as s respectively. Distal calyces spherical; distal part of flagella axes slightly fusiform. Globulus g 1.3 times as long as wide; about 10 bracts, capsule subspherical; width of g 0.6 of the greatest diameter of t . Antennae glabrous. Trunk. Setae on collum subcylindrical, striate; sublateral setae length 25 μm, 3.1 times as long as submedian setae; sternite process triangular, pointed; appendages narrowing distally and with flat caps ( Figs. 8 , 14 ). Tergite I entire, with 4+4 short clavate setae ( Fig. 15 ); Tergites II–V transversally divided into a protergite and a metatergite ( Figs. 17–20 ), 6+6 short clavate setae on II–IV, 6+4 short setae on V; Tergite V with two symmetrical sclerotized patches posteriorly ( Figs. 11 , 20 ); Tergite VI entire, with one sclerotized and thickened middle patch of cuticle, 4+2 cylindrical setae, posterior seta 28 μm ( Fig. 21 ). Tergites I–V coarse granulated and tergite VI pubescent. Bothriotricha. Relative lengths: T 1 = 100, T 2 = 107, T 3 = 82, T 4 =108, T 5 = 128. T 1 , T 2 , T 4 and T 5 slim and long, with dense pubescence on shafts ( Figs. 7 ; 17–21 ). T 3 spatulate with short dense pubescence on axes and coarse granule on distal part ( Figs. 7 , 19 ). Legs. All legs short, leg 1 and 9 5-segmented, others 6-segmented ( Figs. 12 , 22 ). Setae on coxa and trochanter of all legs cylindrical, annulate ( Fig. 22 ), 13 and 15 μm long on leg 9 respectively. Tarsi 1–8 with globular distal seta only ( Fig. 5 ). Tarsus of leg 9 short, 30 μm in length, cylindrical, 2.1 times as long as its greatest diameter ( Fig. 6 ), proximal seta cylindrical, annulate, 12 μm in length; distal globular, 13 μm in length, pubescent; their lengths about 0.4 of the tarsal length. Cuticle of tarsus glabrous. Pygidium. Tergum . Posterior margin undulate. Relative lengths of setae: a 1 = 10, a 2 = 10, a 3 = 17.5 st = 9. Setae distinctly differentiated, a 1 as large spines, a 2 and a 3 slender and pubescent ( Figs. 9 ; 24, 25 ), st large , globular shaped and pubescent ( Figs. 10 ; 26 ). Distance a 1 – a 1 0.75 of length of a 1 ; distance a 1 – a 2 1.7 times as long as a 2 – a 3 ; distance st–st 1.4 times as long as st and 1.7 times as long as distance a 1 – a 1 . Sternum ( Figs. 10 ; 24 ). Posterior margin with deep indention between b 1 . Relative lengths of setae ( a 1 =10): b 1 = 19, b 2 =14. All setae slender, striate. Distance b 1 – b 1 0.9 of length of b 1 ; distance b 1 – b 2 1.6 times as long as b 2 . Male genital papillae ( Fig. 23 ) glabrous, rounded distally, 1.6 times as long as greatest diameter; seta 0.5 of the length of papilla. Anal plate shown in Figs. 10 and 24 , small, pubescent and complicated, basally divided into two triangular parts; with two pairs of globular appendages, inner one tiny and smaller than outer one. FIGURES 3–10. Psammopauropus macrospinus sp. n. holotype. 3 , head, right side, dorsal view; 4 , antenna, dorsal view; 5 , tarsus of leg 1; 6 , tarsus of leg 9; 7 , T3 and T5; 8 , collum; 9 , tergum of pygidium; 10 , sternum of pygidium. Scale bars: 20 μm. FIGURES 11–16. Psammopauropus macrospinus sp. n. holotype. 11 , habitus, dorsal view; 12 , habitus, ventral view; 13 , head, dorsal view—temporal organs are large oval structures; 14 , collum; 15 , tergite I; 16 , antenna. Scale bar: 100 μm ( 11–12 ); 20 μm ( 13–16 ). FIGURES 17–26. Psammopauropus macrospinus sp. n. holotype. 17–20 , tergites II–V, right side, dorsal view; 21 , tergite VI and pygidium; 22 , leg 5; 23 , male genital papillae; 24 , sternum of pygidium, shows anal plates; 25 , tergum of pygidium, shows spines; 26 , pygidium, shows globular seta st . Scale bars: 20 μm. Etymology. The species name “ macrospinus ” refers to the two large spines on the pygidium. Distribution. China ( Hainan Island). Only known from the type locality.