Tylopus phanluongi, Nguyen, 2012

Nguyen, Anh D., 2012, Tylopus Millipedes In Vietnam (Diplopoda: Polydesmida: Paradoxosomatidae: Sulciferini), With Descriptions Of Five New Species, Raffles Bulletin of Zoology 60 (2), pp. 289-311 : 290-293

Tylopus phanluongi , new species

( Figs. 1 , 2 , 18 )

Material studied. — Holotype: Male in the bottle IEBR-100H, with a label “ Kon Tum Province, Dak Glei District, Ngoc Linh Mountain (15°00'– 15°18'N, 107°41'– 08°01'E), primary forest, 1800–1900 m a.s.l., coll. Nguyen Duc Anh, 11 Mar.2006 – 9 Apr.2006.

Paratypes: 1 female (IEBR-100P), collected together with holotype ; 4 males, 2 females (IEBR-101), Kon Tum Province, Dak Glei District, Ngoc Linh Mountain (15°00'– 15°18'N, 107°41'– 08°01'E), secondary forest, 1700 m a.s.l., coll. Nguyen Duc Anh, 25 Mar.2004 – 11 Apr.2004 ; 4 males, 2 females (IEBR-102), Kon Tum Province, Dak Glei District, Ngoc Linh Mountain (15°00'– 15°18'N, 107°41'– 08°01'E), primary forest, 1900–2100 m a.s.l., coll. Nguyen Duc Anh, 21 Mar.2006 – 9 Apr.2006 .

Diagnosis. — The species is very similar to Tylopus hilaris and T. hilaroides in general appearance and gonopod conformation, but it can be distinguished from them in having the gonopod process h with two branches (one spiniform, and the other a serrated lamina).

Etymology. — “ phanluongi ”, named in honour of Dr. Phan Luong of the Vietnamese-Russian Tropical Center for his major contribution to the ecological surveys in Vietnam.

Description. — Size: Body length 37–[40]– 41 mm (male), 38–42 mm (female), width of midbody prozona 3.1–[3.3]– 3.4 mm (male) and 3.2–3.6 mm (female), and metazona 4.1–[4.3]– 4.4 mm (male) and 4.2–4.6 mm (female).

Colouration: Body generally castaneous brown, but margin of posterior part of prozona, anterior area of metazona, metatergal transverse sulcus, distal part of antennomere 6, and whole antennomere 7 blackish brown. Legs, paraterga and sterna brownish yellow.

Head: Slightly broader than collum. Region between antennal sockets with sparse setae, labrum more setose. Frons slightly convex, divided into two parts by a distinct epicranial suture. Antenna long, claviform, reaching body ring 4 laterally. Antennomere 3=4=5>6=2>1& 7 in length.

Collum: Slightly narrower than body ring 2; surface shining, finely rugose in anterior half and strongly rugose in posterior half, without granules or tubercles, with a row of 4+4 setae near anterior margin. Transverse sulcus vestigial, partly obliterated. Paratergum minute, sub-semicircular.

Body ring 3<2=4<5 in width, body parallel-sided on rings 5–16, thereafter gradually tapering towards telson. Surface of prozona shining, smooth. Metatergal surface shining, slightly rugulose on anterior half and considerably rugose on posterior half. Metatergal transverse sulcus present on body rings 5–19, finely striate, reaching base of paraterga ( Fig. 1A ). Metaterga of body rings 2–16 with rows of 2+2 and of 3+3 setae in front of and behind transverse sulcus, respectively.

Metaterga: Body rings 17–18 with three rows of 2+2, 1+1 and 4+4 setae; second and third rows located behind transverse sulcus. Metatergum 19 with rows of 2+2 and 5+5 setae in front of and behind transverse sulcus, respectively.

Pleura: With dense microgranules. Pleurosternal keels small, beak-like or spiniform on body rings 2–5, absent on subsequent body rings. Axial line evident only in anterior half of metaterga. Waist between pro- and metazona narrow, deep, finely striate.

Paraterga: Well developed, slightly lower than metatergal surface, beak-like on body rings 5–14, more protruding on body rings 15–19. Paraterga surpassing posterior contour of metaterga. Calluses small, with one or two setiferous incisions on lateral side of poreless and pore-bearing paraterga, respectively. Ozopores located on lateral side of paraterga of body rings 5, 7, 9–10, 12–13, 15–19 ( Fig. 1A ).

Telson: Epiproct short, broadly truncated, with two small terminal tubercles. Tip with four spinnerets. Hypoproct trapeziform, with two distolateral setiferous knobs ( Fig. 1B ).

Sterna densely setose, without any modification; transverse and longitudinal sutures distinct. Male sternum 5 with a setiferous bifid lamina between coxae 4 ( Fig. 1C ).

Legs: Slender, about 1.8–2 times as long as midbody height, without tarsal brushes. Prefemora swollen dorsally. Ventral part of prefemora and femora with dense microtubercles ( Fig. 1D ).

Gonopods ( Figs. 1E,F , 2A,B ): Coxite cylindrical, slightly shorter than femorite; distoventral part sparsely setose. Prefemorite densely setose, set off from femorite by an oblique sulcus on lateral side. Femorite stout, expanded distally. Postfemoral region demarcated from femorite by a distinct sulcus laterally. Lamina l present, somewhat overlapped by a well-developed, serrated process z. Process h short, with 2 branches, one longer and spiniform, the other shorter and slightly serrated. Lobes m and n absent. Solenophore strongly coiled, completely sheathing flagelliform solenomere.

Distribution. — Known only from the type locality ( Fig. 18 )

Figures

Fig. 1. Tylopus phanluongi, new species, holotype: body ring 10, dorsal view (A); hypoproct, ventral view (B); sternite 5, posterioventral view (C); leg 9 (D); right gonopod, mesal view (E)and lateral view (F). Scale bars = 1 mm.

Fig. 2. Tylopus phanluongi, new species, holotype: right gonopod, mesal view (A); postfemoral region, mesal view (B).

Fig. 18.Distribution map ofthe millipede genus Tylopus Jeekel, 1968 in Vietnam. 1: Sa Pa, Lao Cai Prov. (T. crassipes, T. procurvus, T. nodulipes, T. sigma, T. sapaensis, T. maculatus, T. magnicus); 2: Van Ban, Lao Cai Prov. (T. crassipes, T. nodulipes); 3: Xuan Son NP (T. strongylosomoides, T. golovatchi); 4: Tam Dao NP (T. tamdaoensis, T. roseiparaterga, T. strongylosomoides); 5: Cuc Phuong NP (T. granulatus, T. hilaroides, T. topali); 6: Pu Mat NP (T. nodulipes); 7: Huong Son, Ha Tinh prov. (T. nodulipes); 8: Bach Ma–Ba Na NP (T. hilaris, T. multilatus); 9: Ngoc Linh Mts., Kon Tum prov. (T. hilaris, T. phanluongi); 10: Bi Doup–Nui Ba NP (T. spinisterna).