Tylopus extremus, Likhitrakarn, Natdanai, Golovatch, Sergei I., Prateepasen, Rujiporn & Panha, Somsak, 2010

Likhitrakarn, Natdanai, Golovatch, Sergei I., Prateepasen, Rujiporn & Panha, Somsak, 2010, Review of the genus Tylopus Jeekel, 1968, with descriptions of five new species from Thailand (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 72, pp. 23-68 : 28-30

Tylopus extremus sp. n. Figs 79

Holotype

♂ (CUMZ), Thailand, Chiang Mai Province, Fang District, Doi Phahom Pok National Park, 6.07.2009, leg. A. Pansook.

Paratypes:

1 ♂, 1 ♀ (CUMZ), 1 ♂ (ZMUC), 1 ♂ (ZMUM), same locality, together with holotype.

Name:

To emphasize the extremely long spines h and m of the gonopod.

Diagnosis:

Differs from congeners in process h being subflagelliform while process m extremely long and prominent.

Description:

Length ca 30 mm (holotype), 27-30 mm (♂), 32.5 mm (♀), width of midbody pro- and metazona 2.0 and 2.9 mm (holotype), 1.9-2.4 and 2.8-3.3 mm (♂), 2.5 and 3.0 mm (♀), respectively. Coloration of live animals, as well as of alcohol material black-brown (Fig. 7 A–G): calluses of paraterga and antennae only slightly lighter, light brown to brown, venter and legs contrastingly light, yellow (Fig. 7 A–G), tip of antennae pallid.

All characters as in Tylopus bispinosus sp. n., except as follows.

Antennae rather short and slender, reaching behind to end of segment 3 (♂) dorsally. Collum with paraterga like rudimentary flaps, especially poorly developed in ♀. In width, head <collum = segments 3-4 <2 <5-16 (♂) (Fig. 7B), or head <collum <segment 3 <2 and 4 <5-16(♀); thereafter body gradually and gently tapering towards telson.

Metaterga with two transverse rows of rather long setae: 2+2 in anterior and 2(3)+2(3) in posterior row, the latter often abraded, but then readily traceable as insertion points on low longitudinal ridges or tubercles (Fig. 7 B–G). Axial line thin, visible on both halves of metaterga. Paraterga strongly developed (Fig. 7 A–G), lying rather low (at 1/2-1/3 midbody height), slightly inclined laterally, pointed caudally and acutangular already from segment 2, especially strongly so on caudal segments, very clearly surpassing rear contour only on segments 16-19; anterior 1/3 of poreless calluses with two barely visible, lateral, setigerous incisions, but with only a single, likewise poorly developed incision anteriorly on pore-bearing calluses (Fig. 7 B–F); paraterga slightly less strongly developed in ♀. Transverse sulcus evident on metaterga 5-18, reaching bases of paraterga, evident and rather deep, faintly rugulose at bottom. Stricture between pro- and metazona weakly striolate (Fig. 7 B–G). Epiproct emarginate at tip, pre-apical papillae evident (Fig. 7G). Hypoproct subtrapeziform, caudal setae widely separated (Fig. 7H). Pleurosternal carinae as compete ridges with a caudal tooth on segments 2-4 (♂) or 2 and 3 (♀), like separated anterior bulges and increasingly poorly developed caudal denticles until segment 16 (Fig. 7C, E, F).

Sterna moderately setose, without modifications; an entire, linguiform, sternal lobe between ♂ coxae 4 (Fig. 7I, J). Legs long, in ♂ very distinctly incrassate, 1.7-2.0 or ca 1.3 times as long as midbody height in ♂ and ♀, respectively (Fig. 7B, C, H), ♂ prefemora very distinctly bulged laterally and clothed with dense and adpressed pilosity ventrally (Fig. 7K), acropodites also with similarly dense and ventrally adpressed pilosity, including tarsal brushes. All ♂ postfemora and tibiae except for a few posteriormost ones with a small, but evident adenostyle (= tubercle) at midway on ventral side (Fig. 7K).

Gonopods (Figs 8, 9) with lobe l well-demarcated, but unusually prominent, high and elongated; spine h long, extremely slender and subflagelliform; spine z rather short and simple; spine m very prominent, straight and long.