Tylopus golovatchi, 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 : 298

Tylopus golovatchi , new species

( Figs. 7 , 8 , 18 )

Material examined. — Holotype: Male in a bottle IEBR-141H with a label “ Phu Tho province, Xuan Son National Park (21°03'– 21°12'N, 104°51'– 105°01'E), primary forest, coll. Nguyen Van Quang, 15 Jan.2006 ”.

Paratype: 1 female (IEBR-141P), collected together with holotype .

Etymology. — “ golovatchi ”, named in honor of Dr. S. I. Golovatch, an outstanding specialist of millipedes for his major contribution to global myriapodology.

Diagnosis. — The species is very similar to Tylopus strongylosomoides , but it can be easily distinguished from the latter by the presence of a long, slender, finger-shaped process h on the gonopod.

Description. — Size: Body length about [17.9] mm (male), 21.3 mm (female). Width of midbody prozona [1.6] mm (male), 2.2 mm (female) and metazona [1.9] mm (male), 2.6 mm (female).

Colouration: Body generally yellowish brown except legs and sterna paler; whole antennomere 6 and 7 blackish brown. Prozona and metaterga with several small blackish brown areas. Female generally yellowish.

Head: Slightly broader than collum. Epicranial suture obviously distinct. Antenna claviform, reaching body ring 4 laterally. Antennomere 2=3>4=5>6> 7 in length.

Collum: Slightly narrower than body ring 2, subtrapeziform; surface shining, finely rugulose, with traces of row of 2+2 setae near front margin. Paratergum poorly developed, rounded.

Body ring 3<4<2= 5 in width, parallel-sided on body rings 5–17, thereafter gradually tapering towards telson. Prozona shining, somewhat smooth. Metatergal surface shining, finely rugose, with rows of 2+2 and 3+3 small knobs in front of and behind transverse sulcus, respectively. Transverse sulcus poorly-developed on body rings 2–4, but more distinct and well developed (reaching base of paraterga) on body rings 5–19. Pleura with dense microgranules. Pleurosternal keels well developed on body rings 2–4, beak-shaped on body rings 5–7, reduced on body rings 8–11, and completely absent on subsequent body rings. Waist between pro- and metazona broad, finely striate. Axial line evident.

Paraterga: Poorly developed, somewhat rounded, slightly lower than metatergal surface, not surpassing posterior contour of metaterga 2–17. Caudal corner rounded, neither pointed nor acute. Calluses minute, almost reduced, without any incision laterally. Ozopores located near caudal corner on lateral side of paraterga 5, 7, 9–10, 12–13, 15–19.

Telson: Epiproct short, broadly truncated without terminal tubercles. Tip with four spinnerets. Hypoproct somewhat parabolical, rounded with two distolateral setiferous knobs ( Fig. 7A ).

Sterna: Sparsely setose, without any modifications; longitudinal and transverse sutures obvious. Male sternum 5 with two tooth-shaped laminae and a pair of cones between coxae 4 ( Fig. 7B ).

Legs: Strong (male), thin (female), about 1.4 (male) and 1.3 (female) times as long as midbody height. Prefemora normal, not swollen. Ventral part with large tubercles. Tarsi without setose brushes.

Gonopod ( Figs. 7C–E , 8A–D ): coxite short, with sparsely setose part distoventrally. Prefemur densely setose, set off from femorite by an oblique sulcus laterally. Femorite enlarged distally, slightly twisted and grooved mesally, demarcated from postfemoral region by a V-shaped sulcus laterally. Lamina l subrectangular, concealing a long, slender, finger-shaped process h. Process z, lobes m and n absent. Solenophore strongly coiled, completely sheathing flagelliform solenomere. Tip of solenophore with process k.

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

Figures

Fig. 7. Tylopus golovatchi, new species, holotype: hypoproct, ventral view (A); sternite 5, posterioventral view (B); left gonopod, lateral view (C), mesal view (D); postfemoral region, dorsal view (E). Scale bars = 1 mm.

Fig. 8. Tylopus golovatchi, new species, holotype: left gonopod, mesal view (A), ventral view (B), and lateral view (C); postfemoral region, lateral view (D).

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).