Siphonocryptida, Pocock, 1894

Korsós, Z., Enghoff, H. & Chang, H. W., 2008, A Most Unusual Animal Distribution Pattern: A New Siphonocryptid Millipede From Taiwan (Diplopoda, Siphonocryptida), Acta Zoologica Academiae Scientiarum Hungaricae 54 (2), pp. 151-157 : 152-155

Order Siphonocryptida

Family Siphonocryptidae Genus Hirudicryptus ENGHOFF et GOLOVATCH, 1995 Hirudicryptus taiwanensis sp. n.

Holotype. m, TAIWAN, Taichung County, Heping township, Da-Hsueh-Shan, Anma-Shan , 2000 m a.s.l., soil sample (0–5 cm), 28 May 1996, R.- F. Chao leg. ( NMNS). *

Paratypes. Same data as for holotype, 1 m, 1 f ( HNHM, slide prep.). Same locality, 1 f, 9 December 1995 ( ZMUC) ; same locality, 1 f, 8 February 1996 ( NMNS) ; same locality, 1 juv. f, 4 November 1996 ( NMNS) ; all R.- F. Chao leg. – Ilan County, Chialo-hu, Shiji , N24°28’ E121°28’, 2200 m a.s.l., coniferous forest, 1 m, 20 June 2002 ( HNHM, slide prep.) ; same locality, 1 m, 23 August 2002 ( TFRI) ; same locality, 1 m, 4 June 2003 ( TFRI) ; same locality, open grassland, bushes, 1 m, 23 July 2002 ( TFRI) ; same locality, 2 mm, 4 June 2003 ( ZMUC, SEM prep. & TFRI) ; same locality and date, 2 ff ( MNHN & TFRI) ; Taichung County, Lishan area , Shengwuan, near Wu-Lin, 1 f, 24 February-March 2003 ( TFRI) ; all Y.-M. Chen & W.-C. Yeh leg. – Taichung County, Mt. Shiu-shan, Wuling township , Shiyuan-yako , logging road No. 710, 2050–2100 m a.s.l., 1 f, 21 August 2002, Ch.-Ch. Chen & Y.-H. Lin leg. ( NSYSU) .

Total material: 8 mm, 8 ff.

Etymology. The name refers to the occurrence of the species.

Diagnosis. Differing from H. canariensis , by having a small shoulder-like angle at the base of the posterior gonopod tibiotarsus (somewhat similar to that of S. compactus ), a lower number (6–8, vs. 14–15 on each side) of tubercles on the posterior margins of paraterga, and a sinuous posterior margin of the last tergum (straight in H. canariensis ).

Description. Size and shape. mm 31–46 terga, body length 10.5–16.8 mm, width 1.2–2 mm; ff slightly larger: 32–48 terga, body length 13.7–19.4 mm, width 1.3–2.5 mm. Body regularly rounded at both ends. Body shape, expressed as the relation between number of terga and body width, shown in Fig. 1 .

Colour. Dorsally yellowish, with a narrow dark brown middorsal band and brownish edges on each tergum which combine into additional longitudinal, marginal brown bands ( Fig. 2 ). Head and rostrum are also brownish, gnathochilarium yellow ( Fig. 3 ). Ventrally completely yellow. Smaller specimens with less conspicuous colour pattern.

Head completely hidden under collum in dorsal view. Gnathochilarium with 2–3 pairs of larger setae and several small apical setae. Antennae long and slender, with seven visible antennomeres, antennomeres 1–6 almost equally long, 7 much shorter. Two ocelli on each side, the posterior

* Acronyms of collections where the material is deposited are HNHM = Hungarian Natural History Museum, Budapest, Hungary ; MNHN = Muséum national d’Histoire naturelle, Paris , France ; NMNS = National Museum of Natural Science , Taichung, Taiwan ; NSYSU = National Sun Yat-Sen University, Kaohsiung, Taiwan ; TFRI = Taiwan Forestry Research Institute, Taipei, Taiwan ; ZMUC = Zoological Museum, Natural History Museum of Denmark , Copenhagen, Denmark .

one larger ( Figs 4–5 ), each pair of ocelli in a blackish patch. A pair of long frontal setae. Rostrum somewhat curved downwards ( Fig. 5 ), otherwise straightly tapering.

Collum crescent-shaped, with slightly developed anterio-ventral “ears” (“e” in Fig. 4 ). (A similar structure occurs also in H. canariensis although it was not reported by ENGHOFF & GOLOVATCH 1995). Surface of collum smoother than in H. canariensis , posterior row of tubercles similar to following terga.

Body terga without setae, ca. 4× as broad as long, shallowly domed. A distinct mid-dorsal suture along entire body length (“s” in Fig. 2 ). A transverse ridge on each tergum at ca. 1/6 from anterior margin. Surface microtuberculate. Paraterga moderately developed, slightly bent caudad, more conspicuously so towards the posterior ( Fig. 6 ), regularly overlying following paratergum from collum onwards. A transverse row of larger, dark tubercles on posterior margin of each paratergum. These tubercles less numerous and not as evenly distributed compared to H. canariensis ( Figs 7–8 ). H. canariensis : 14–15 tubercles on each side of midbody terga; H. taiwanensis :only 6–8 tubercles on each side only, sometimes arranged pairwise. Suture between tergum and pleuron obliterated. Lateral margin with posterolateral corners acutangular, bent caudad (more than in H. canariensis ) from fifth to last tergum with peritreme for ozopore. Peritreme situated in anterior 1/3 of margin on tergum 5, in posterior 1/ 3 in other terga ( Figs 9–10 ). Last tergum large, subtrapezoid, with sinuous posterior margin (straight in H. canariensis ) ( Figs 11–12 ).

Sterna ca 2/3 as wide as coxa.

Telson small, hidden under last tergum in dorsal view; preanal ring completely surrounding anal valves, with a pair of long setae.

Legs almost reaching lateral body margin. No accessory claw.

Male sexual characters

Second pair of legs as in Siphonocryptida in general. Penes bottleshaped, clearly delimited from coxae (Fig. 13) (autapomorphy for the genus Hirudicryptus , see Discussion).

Anterior gonopods (P9) leglike, incrassate, with six clearly separated podomeres. Terminal podomere drawn out into long, slightly twisted projection, similar to an open tube (t), probably for accomodation of the long terminal projection of the posterior gonopod (Figs 14–15). Three to four long setae situated dorsally to projection.

Posterior gonopods (P10) leglike, slenderer than P9, with five clearly separated podomeres. Terminal podomere drawn out into long, thin projection (p) showing a clearly visible, distinct shoul- der (s) at its proximal third (Fig. 14).

body end with paraterga bent caudad, dorsal view

Female sexual characters

Second pair of legs with separate coxae. Vulvae large, embedded in coxae. ( LOKSA, 1967), 12 = H. taiwanensis sp. n.

Figures

Fig. 1. Body shape, expressed as the relation between number of terga and body width of Hirudicryptus taiwanensis sp. n.

Figs 2–6. Hirudicryptus taiwanensis sp. n.: 2 = holotype body pattern, dorsal view, 3 = holotype head, frontal view, 4 = paratype from Shiji, head and collum in frontal view (right antenna broken), scanning electron micrograph, 5 = head, right fronto-lateral view, scanning electron micrograph, 6 = holotype,

Figs 7–12. Scanning electron micrographs of Hirudicryptus spp.: 7–8 = caudal edge of midbody terga with pattern of tubercles: 7 = H. canariensis (LOKSA, 1967), 8 = H. taiwanensis sp. n.; 9–10 = left lateral edge of midbody segments with peritreme: 9 = H. canariensis (LOKSA, 1967) with ozopores (o), 10 = H. taiwanensis sp. n.; 11–12: caudal margin of last tergum: 11 = H. canariensis