Tylopus retusus Likhitrakarn & Golovatch & Panha 2016, sp. nov.
Creators: name: Likhitrakarn, Natdanai
name: Golovatch, Sergei I.
name: Panha, Somsak
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Diplopoda
Polydesmida
Paradoxosomatidae
Tylopus
Tylopus retusus

description: Tylopus retusus sp. nov.
urn:lsid:zoobank.org:act: 40D74A7C-61D7-442B-B388-3868C47102C5
Figs 10 – 11, 26
Diagnosis
Distinguished by its relatively small body with four transverse rows of setae forming no regular pattern of setation; in gonopod structure it is similar to T. haplorugosus Golovatch & Enghoff, 1993, but differs in process h being rather short, slightly flattened, blunt, coupled with the solenophore being strongly coiled.
Etymology
To emphasize the blunt tip of process h; adjective.
Material examined
Holotype
LAOS: ♂, Muang Xay City, Xay, Oudomxai, 20°41'00" N, 101°59'05" E, ca 640 m a.s.l., mango garden, 14 Oct. 2014, leg. C. Sutcharit & R. Srisonchai (CUMZ).
Paratype
LAOS: 1 ♀, Khoua, Phongsaly, ca 835 m a.s.l., 21°11'55" N, 102°06'40" E, forest near road, 15 Oct. 2014, leg. C. Sutcharit & R. Srisonchai (CUMZ).
Description
MEASUREMENTS AND COLOUR. Length 16.3 (♂) or 20.4 mm (♀), width of midbody pro- and metazonae 1.12 and 2.07 mm (♂) or 2.7 and 3.7 mm (♀), respectively. Live coloration light brown (Fig. 10A); prozonae dark brown; paraterga, antennae, head and legs light brown to yellow-brown. Coloration of alcohol material after one year of preservation faded to light brown to yellow-brown; paraterga, antennae, head, legs and venter light brown to light yellow (Fig. 10 B–J).
HEAD. Clypeolabral region and vertex sparsely setose, epicranial suture distinct. Antennae (Fig. 10A, B) rather short and stout, antennomeres 2–6 subequal in length, reaching body segment 3 (♂, ♀) when stretched dorsally. In width, head <segment 3 <4 <collum <segments 5–15; thereafter body gently and gradually tapering. Collum with three transverse rows of setae: 6+6 anterior, 4+4 intermediate and 6+6 posterior; a small lateral incision at about midway; caudal corner very broadly rounded, paraterga declined ventrad, slightly produced behind rear tergal margin.
BODY. Tegument smooth and shining, prozonae finely shagreened, metaterga leathery, finely rugulose (Fig. 10B, D, F); surface below paraterga roughly microgranulate (Fig. 10C, E, H). Postcollum metaterga with four transverse rows of setae forming no regulated pattern of setation, anterior row with the most dense setae growing increasingly dense towards segment 19 (Fig. 10B, D, F). Tergal setae long and slender, about 2/3 as long as metaterga. Axial line well visible on metazonae, traceable also on prozonae. Paraterga strongly developed (Fig. 10 B–H), especially so in ♂, set rather high (at upper 1/3 of body height), slightly upturned, but lying below dorsum; anterior edge broadly rounded and narrowly bordered, fused to callus; caudal corner very narrowly rounded, starting with segment 16 extending increasingly behind rear tergal margin (Fig. 10F, H). Paraterga 2 and 3 with two evident incisions at lateral edge (Fig. 10B). Following poreless segments with two similar incisions; pore-boring segments with one, often setigerous incision lying in front of pore (Fig. 10D, E). Calluses of paraterga delimited by a sulcus both dorsally and ventrally. Ozopores evident, lateral, lying in an ovoid groove at about 1/3 of metatergal length in front of posterior edge of metaterga. Transverse sulcus usually distinct (Fig. 10B, D, F), slightly incomplete on segment 19, complete on segments 5–18, narrow, undulate, shallow, not reaching bases of paraterga, beaded at bottom. Stricture between pro- and metazonae evident, wide and deep, beaded at bottom down to base of paraterga (Fig. 10B, D – F). Pleurosternal carinae complete crests with a sharp caudal tooth on segments 2–7 (♂) or 2–4 (♀), thereafter increasingly reduced to a small tooth until segment 15 (♂) or 13 (♀), missing more caudally. Epiproct (Fig. 10 F–H) conical, flattened dorsoventrally, with two evident, large, rounded apical papillae; tip subtruncate; lateral preapical papillae small, lying close to tip. Hypoproct (Fig. 10G) roundly subtrapeziform, setigerous knobs at caudal edge small and well-separated.
STERNA. Densely setose, with a small cone caudally near each coxa, rear cones being a little larger than fore ones (Fig. 11E); two small, rough, fully separated, setose cones between ♂ coxae 4 (Fig. 10I, J). Legs rather long and slender, midbody ones ca 1.2–1.3 (♂) or 0.9–1.0 (♀) as long as body height; all male legs until segment 16 with tarsal brushes, prefemora not swollen; prefemora, femora and tibiae with ventral microgranulations; femora, tibiae and tarsi each with an evident adenostyle (tubercle) medially (Fig. 11F – G).
GONOPOD. Rather simple (Fig. 11 A–D); coxa a little curved caudad, sparsely setose distoventrally. Femorite slightly curved and stout, with an evident mesal groove and a clear distolateral sulcus demarcating a postfemoral part; lobe l evident, rounded, with process h rather short, slightly flattened, blunt; solenophore (sph) strongly coiled, devoid of processes, pointed.
Remark
This species was found in a mango plantation in Muang Xay City.
description: Published as part of Likhitrakarn, Natdanai, Golovatch, Sergei I. & Panha, Somsak, 2016, The millipede genus Tylopus Jeekel, 1968 (Diplopoda, Polydesmida, Paradoxosomatidae), with a key and descriptions of eight new species from Indochina, pp. 1-47 in European Journal of Taxonomy 195 on pages 14-17, DOI: 10.5852/ejt.2016.195, http://zenodo.org/record/3837846