Tylopus hilaris (Attems, 1937)

Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2014, Three new species of the millipede genus Tylopus Jeekel, 1968 from Thailand, with additional notes on the species described by Attems (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 435, pp. 63-91 : 77-80

Taxon classification Animalia Polydesmida Paradoxosomatidae

Tylopus hilaris (Attems, 1937) Figs 10, 11

Anoplodesmus hilaris Attems, 1937: 105 (D).

Anoplodesmus hilaris - Attems 1938: 215 (D).

Agnesia hilaris - Jeekel 1965: 97 (M, D).

Tylopus hilaris - Jeekel 1968: 60 (M); Hoffman 1973: 371 (M, D); Golovatch 1983: 182 (M); 1984: 69 (M, D); Golovatch and Enghoff 1993: 90 (M, D); Enghoff et al. 2004: 40 (R); Likhitrakarn et al. 2010: 25 (R, D); Nguyen 2012: 301 (R, D).

Holotype

♂ of Anoplodesmus hilaris (NHMW-4248), Vietnam, Danang Prov., Mount Bana, 1,500 m, 28.09.1931, leg. C. Dawydoff.

Redescription.

Length ca 38 mm, width of midbody pro- and metazonae 3.7 and 5.1 mm, respectively (vs 3.4 and 5.0 mm in width, as given in the available descriptions ( Attems 1937, 1938)). Coloration of alcohol material after long preservation brown (Fig. 10 A–G) with light yellow antennae, paraterga, epiproct and legs (versus dark brown with prozonae and posterior halves of metazonae blackish brown; edge of paraterga, antennae and legs yellowish brown, as given in the descriptions ( Attems 1937, 1938)).

Clypeolabral region densely setose, vertex smooth, epicranial suture distinct. Antennae rather long (Fig. 10A, B), reaching behind body segment 3 when stretched dorsally. In width, head <segments 3 and 4 <collum <2 <5-16, gently and gradually tapering thereafter. Collum smooth, with three transverse rows of setae, 4+4 anterior, 2+2 intermediate, and 3+3 posterior; caudal corner of paraterga subrectangular, narrowly rounded (Fig. 10A, B). Tegument smooth and shining; metaterga faintly rugulose, prozonae finely shagreened, surface below paraterga finely microgranulate. Postcollum metaterga with an anterior transverse row (pre-sulcus) of 2+2, mostly abraded setae; caudal (post-sulcus) row barely traceable as 3+3 insertion points. Tergal setae short, simple, slender, about 1/5 metatergal length. Axial line barely visible, starting from collum. Paraterga very strongly developed (Fig. 10 A–F), all subhorizontal and lying below dorsum, thin blunt blades in lateral view, a little thicker only on pore-bearing segments, on postcollum segments extending increasingly beyond rear tergal margin, nearly pointed to pointed, caudal tips on paraterga 17-19 evidently curved mesad. Calluses delimited by a sulcus only dorsally, rather narrow. Paraterga 2 broad, anterior edge rounded, lateral edge with three small incisions in anterior half; posterior edge concave (Fig. 10A). Anterior edge of postcollum segments broadly rounded, bordered and fused to callus, lateral edge with two small incisions in anterior half on poreless segments, with only one incision near front 1/3 on pore-bearing ones; posterior edge oblique. Ozopores evident, lateral, lying inside an ovoid groove at about 1/4 metazonital length in front of caudal corner. Transverse sulcus complete on metaterga 5-18, incomplete on metaterga 4 and 19, rather deep, wide, line-shaped, reaching bases of paraterga, ribbed at bottom (Fig. 10A, C, F). Stricture between pro- and metazonae shallow, broad, beaded at bottom down to base of paraterga. Pleurosternal carinae complete crests only on segment 2 (Fig. 10B), with a sharp tooth caudally on segments 3-7, only a small sharp caudal tooth on segments 8-16, onward missing (Fig. 10A, D, E). Epiproct (Fig. 10 E–G) conical, flattened dorsoventrally, apical papillae very small; tip subtruncate; pre-apical papillae very small, lying close to tip. Hypoproct (Fig. 10G) roundly subtriangular, setiferous knobs at caudal margin small and well-separated.

Sterna sparsely setose, until segment 6 with an evident cone caudally near coxae; on segment 4 with an evident, central cone between coxae; on segment 5 with a small central lobe with a paramedian pair of evident, sparsely setose, apical cones between coxae (Fig. 10H, I). Legs long and slender, midbody ones ca 1.2-1.3 (♂) or 0.8-0.9 (♀) times as long as midbody height, all legs until segment 17 with an evident adenostyle on each postfemur and tibia (Fig. 11C); tarsal brushes absent.

Gonopods (Fig. 11A, B) simple; coxa a little curved caudad, sparsely setose distoventrally. Prefemur densely setose, about 1/3 as long as femorite + “postfemoral” part. Femorite rather stout, expanded distad, slightly curved, showing a mesal groove; lobe l simple; process z with two small spines along ventral margin; process h short and stout, curved, tip acute; solenophore long and slender, typically coiled, tip subtruncate.

Remark.

Endemic to Vietnam, Tylopus hilaris is currently known from Mount Bana, 1,500 m a.s.l., Danang Province (Attems, 1937); Bach Ma National Park (16°05'-16°05'N, 107°43'-107°53'E), Thua Thein Hue Province; Mount Ngoc Linh (15°00'-15°18'N, 107°41'-108°01'E), Kon Tum Province, central Vietnam ( Nguyen 2012).