Chamberlinius pessior, Chen, Chao-Chun, Golovatch, Sergei I., Chang, Hsueh-Wen & Chen, Shyh-Hwang, 2011

Chen, Chao-Chun, Golovatch, Sergei I., Chang, Hsueh-Wen & Chen, Shyh-Hwang, 2011, Revision of the Taiwanese millipede genus Chamberlinius Wang, 1956, with descriptions of two new species and a reclassification of the tribe Chamberlinini (Diplopoda, Polydesmida, Paradoxosomatidae, Paradoxosomatinae), ZooKeys 98, pp. 1-27 : 10-12

Chamberlinius pessior sp. n. Figs 17 –2436–3849– 52

Holotype

♂ (NTNUL-My 74), Taiwan, Nantou County (南投縣), Renai Township (仁愛鄉), Lushan warm spring (廬山溫泉), ca. 1,200 m a.s.l., 29 August 1988, leg. S. H. Chen.

Paratypes:

1 ♂, 5 ♀ (NTNUL-My 75-80), same locality and date, together with holotype.

Name:

To emphasize the lower paraterga.

Diagnosis:

Closest to Chamberlinius hualienensis , but differs in being obviously smaller, with paraterga like low ridges (versus higher ridges in Chamberlinius hualienensis ), the pleurosternal carinae are with small caudal teeth on segments 3-10 (versus 3-7(8) in Chamberlinius hualienensis ), legs with tarsal brushes (versus without in Chamberlinius hualienensis ) and the gonopods showing the tip of the solenophore pointed and simple (versus bifid in Chamberlinius hualienensis ).

Description:

Length 25-26 (♂, n = 2) or 27-29 mm (♀, n = 5), width of metazonite 10 ca. 3.5-3.8 (♂) or 3.8-4.0 mm (♀). Coloration in alcohol (Fig. 17) almost entirely light yellow-brown in ♂, but infuscate (brown) in ♀ compared with ♂; colour pattern same as in Chamberlinius hualienensis .

In width, head <collum = segment 2> 3 <4 << 5 <6 <7 <8 <9 <10 <11 <12 <13 <14 <15 <16 in ♂, or head <collum = segment 2> 3 <4 <5 <6 <7 <8 <9 <10 <11-16 in ♀; thereafter body gradually and gently tapering both in width and height towards telson. Antennae (Figs 17, 18) long and slender, reaching behind middle of metatergum 4 (♂) or 3 (♀) dorsally. Surface generally shining and smooth, rugulose (r) (Figs 18, 20, 49) on metaterga on place and below paraterga 2-19, metazona below paraterga evidently and densely granular on segments 2-19 in both sexes. Paraterga (Fig. 19) very well-developed, calluses (Figs 19, 20) delimited by a sulcus dorsally and ventrally on segments 2-19; paraterga like low ridges (Figs 20, 49), slightly extending beyond caudal tergal margin on segments 2-4, obviously beyond it on segments 5-19 (Fig. 17), spiniform caudally (Fig. 22) on segments 17-19 in both sexes; anterior corner of paraterga thinner dorsoventrally and depressed only in ♂. Axial line traceable to evident on pro- and metaterga from collum to anterior part of segment 19 in ♂, fainter in ♀. Transverse sulcus (Figs 19, 49) evident on segments 5-17, traceable on segment 18, wanting on segment 19 in both sexes, narrow, shallow (markedly shallower in ♂ as compared to ♀), neither beaded at bottom nor reaching bases of paraterga. Limbus thin, caudal margin entire. Stricture (Fig. 19) between pro- and metazona roughly beaded, evidently more roughly so in ♀ as compared to ♂. Pleurosternal carinae (Figs 18, 20) well-developed on segments 2-10, traceable on segments 11-15 in ♂, well-developed on segments 2-12, visible on segments 13-17 in ♀, thereafter wanting, with small caudal teeth on segments 3-10 (♂) or 3-9 (♀). Tergal setae fully abraded, pattern untraceable in both sexes. Ozopores (Figs 20, 49) lateral, lying on callus about one-third metatergal length in front of caudal edge. Epiproct (Figs 21, 22) digitiform, long, flattened dorsoventrally, curved and directed caudoventrad in lateral view (Fig. 22), ratio of epiproct length to pre-epiproct length of telson 1: 2.0 in ♂ (Fig. 22), subtruncate and emarginated (♂) or slightly concave (♀) in dorsal view (Fig. 21); pre-apical papillae (Fig. 21) evident, situated close to apex. Hypoproct (Fig. 23) subtrapeziform, caudally convex, 1+1 setae at caudal corners situated on well-separated knobs, sides slightly concave in both sexes.

Sterna moderately setose in ♂, sparsely so in ♀; an obvious, short, round, spiracle-bearing ridge flanking gonopod aperture (Fig. 24, arrows); each cross-impression with an evident transverse sulcus, without axial groove. Legs (Fig. 49) with tarsal brushes, long, ca. 1.2 times midbody height in ♂, slightly shorter in ♀.

Gonopods (Figs 36-38, 50-52) as in Chamberlinius hualienensis , but solenophore (sph) not bifid, being simple and pointed.

Remarks.

Chamberlinius pessior sp. n. is endemic to Taiwan, being known from a single locality at 1,200 m a.s.l. (Map).