Desmoxytes purpurosea Enghoff, Sutcharit & Panha, 2007

Srisonchai, Ruttapon, Enghoff, Henrik, Likhitrakarn, Natdanai & Panha, Somsak, 2018, A revision of dragon millipedes I: genus Desmoxytes Chamberlin, 1923, with the description of eight new species (Diplopoda, Polydesmida, Paradoxosomatidae), ZooKeys 761, pp. 1-177 : 1

Desmoxytes purpurosea Enghoff, Sutcharit & Panha, 2007 Figs 75, 76, 77, 78, 79, 80, 81

Desmoxytes purpurosea Enghoff, Sutcharit & Panha, 2007: 32. Nguyen and Sierwald 2013: 1242.

Material examined.

Hototype: Male (CUMZ), THAILAND, Uthai Thani Province, Department of National Parks, Tam Pratun Non-Hunting Area, Hup Pa Tard. 15°22'38"N, 99°37'50"E, ca. 113 m a.s.l., 28 August 2006, leg. S. Panha, H. Enghoff, P. Pimwichai, and C. Sutcharit.

Paratypes.

16 males, 30 females (CUMZ), 4 males, 3 females (ZMUC), same data as holotype.

Further specimens,

all from THAILAND, Kanchanaburi Province: 8 males, 5 females, 1 broken male, 1 male missing gonopods, 1 male missing left gonopod, 1 fragment, 1 juvenile (CUMZ), Sai Yok District, Daowadueng Cave, 14°28'23"N, 98°50'04"E, ca. 132 m a.s.l., 11 July 2009, leg. S. Panha and ASRU members. 1 male (CUMZ), Sai Yok District, Daowadueng Cave, 14°28'23"N, 98°50'04"E, ca. 132 m a.s.l., 12 October 2015, leg. C. Sutcharit and R. Srisonchai. 14 males, 7 females (CUMZ), Sai Yok District, Daowadueng Cave, 14°28'23"N, 98°50'04"E, ca. 132 m a.s.l., 15 August 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 3 males, 1 female (CUMZ), Sai Yok District, Ban Thung Kang Yang, 14°24'17"N, 98°55'04"E, ca. 264 m a.s.l., 15 August 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 38 males, 13 females (CUMZ), Sai Yok District, Wat Sunantha Wanaram, 14°32'11"N, 98°49'51"E, ca. 161 m a.s.l., 17 August 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 1 male (CUMZ), Si Sawat District, Chalermrattanakosin National Park, Tham Than Lod Cave, 14°40'06"N, 99°19'02"E, ca. 255 m a.s.l., 9 September 1973, leg. CUMZ staff. Many specimens (CUMZ), Si Sawat District, Chalermrattanakosin National Park, Tham Than Lod Cave, 14°40'06"N, 99°19'02"E, ca. 255 m a.s.l., 10 July 2006, leg. CUMZ staff. 6 males, 4 females (CUMZ), Si Sawat District, Chalermrattanakosin National Park, Tham Than Lod Cave, 14°40'06"N, 99°19'02"E, ca. 255 m a.s.l., 13 October 2015, leg. C. Sutcharit and R. Srisonchai. 1 male missing gonopods, 2 females (CUMZ), Sangkhla Buri District, Kroeng Krawia Waterfall, 14°58'56"N, 98°37'55"E, ca. 264 m a.s.l., 10 July 2009, leg. S. Panha and ASRU members. 7 males, 12 females (CUMZ), Thong Pha Phum District, Kroeng Krawia Checkpoint, 14°56'32"N, 98°40'11"E, ca. 347 m a.s.l., 16 August 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members.

Lamphun Province: 1 male (CUMZ), Pasang District, Tham Erawan (Erawan Cave), 18°19'35"N, 98°52'24"E, ca. 551 m a.s.l., 26 October 2015, leg. C. Sutcharit, R. Srisonchai, and ASRU members.

Suphan Buri Province: 3 juveniles (CUMZ), Dan Chang District, Tham Weruwan, 14°57'17"N, 99°38'49"E, ca. 121 m a.s.l., 5 June 2017, leg. C. Sutcharit, A. Pholyotha, and ASRU members.

Uthai Thani Province: 1 male missing gonopods (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 8 June 2008, leg. S. Panha and ASRU members. 7 males, 9 females, 1 broken female, 1 male missing gonopods (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 15 May 2009, leg. S. Panha and ASRU members. 5 females (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., April 2009, leg. S. Panha and ASRU members. 1 male, 3 broken and mixed males (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 27 October 2013, leg. S. Panha and ASRU members. Many specimens (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 31 May 2009, leg. S. Panha and ASRU members. Many specimens (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 7 June 2008, leg. S. Panha and ASRU members. Many specimens (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 10 September 2006, leg. S. Panha and ASRU members. Many specimens (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., unknown date, unknown collector. 1 female (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 27 October 2013, leg. S. Panha and ASRU members. 2 males, 1 female (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 1 August 2014, leg. S. Panha and ASRU members. 34 specimens (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 20 October 2015, leg. C. Sutcharit and R. Srisonchai. 4 males, 1 female (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 27 July 2006, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 1 male, 1 female (ZMUC), 1 male, 1 female (ZMUM), 1 male, 1 female (NHMW), 1 male, 1 female (NHMUK), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 27 July 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 9 males, 1 female, 6 broken males and 4 broken females mixed together (CUMZ), Lansak District, Hup Pa Tard, 15°22'26"N, 99°37'58"E, ca. 113 m a.s.l., 19 August 2017, leg. R. Srisonchai and ASRU members. Many specimens (CUMZ), Lansak District, Tham Pha Nam Thip Bureau of Monks, 15°26'03"N, 99°35'24"E, ca. 245 m a.s.l., 27 July 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. 17 males, 6 females (CUMZ), Lansak District, Tham Pha Nam Thip Bureau of Monks, 15°26'03"N, 99°35'24"E, ca. 245 m a.s.l., 19 August 2017, leg. R. Srisonchai and ASRU members. 4 males, 6 females, 1 broken male, 2 broken females (CUMZ), Lansak District, Wat Wang Pong (Wat Tham Khoa Chong Lom), 15°16'50"N, 99°43'11"E, ca. 90 m a.s.l., 28 July 2016, leg. C. Sutcharit, R. Srisonchai, and ASRU members. Many specimens (CUMZ), Ban Rai District, Wat Khao Chuak Charoen Tham, 15°16'19"N, 99°41'43"E, ca. 86 m a.s.l., 8 July 2009, leg. S. Panha and ASRU members. 3 males (CUMZ), Ban Rai District, Wat Tham Khao Wong, 15°01'57"N, 99°27'21"E, ca. 259 m a.s.l., 27 October 2013, leg. S. Sutcharit, R. Chanabun, and S. Siriwut.

Diagnosis.

Differs from all other Desmoxytes species by the combination of the following characters; body purple pink; collum with rows of 4+4 anterior, 1+1 intermediate and 2+2 posterior setiferous tubercles; tip of epiproct slightly or moderately concave; lateral sulcus (ls) deep, long and narrow; lamina lateralis (ll) swollen, surface smooth; ventral lobe (vll) of lamina lateralis long and slender, digitiform, tip round; process (plm) of lamina medialis very long, spine-like, tip usually bifurcating into two distinct spines (in some populations tip terminating in 3-5 spines); distal lobe (dlm) of lamina medialis quite long, distally with two distinct lamellae (mesal lamella smaller and thinner than lateral lamella, tip crenate; lateral lamella broad).

Type locality.

THAILAND, Uthai Thani Province, Lansak District, Department of National Parks, Tam Pratun Non–Hunting Area, Hup Pa Tard.

The updated redescription hereunder is modified from Enghoff et al. 2007; some morphological characteristics have been added which were extracted from the type material and all recently collected specimens.

Redescription.

SIZE: Length 22-34 mm (male), 26-38 mm (female); width of midbody metazona ca. 2 mm (male), 3.4 mm (female). Width of head <collum = body ring 2 <3 = 4 <5-17, thereafter body gradually tapering toward telson.

COLOUR (Fig. 75 A–D): In life with body purple to vivid pink; paraterga and metaterga vivid pink to purple; surface below paraterga brownish pink or pink; head brown or blackish brown; antenna black or blackish brown (except distal part of antennomere 7 and antennomere 8 whitish); leg, sterna and epiproct pink; a few basal podomeres pale pink. Colour in alcohol: after 10-11 years changed brownish white, after 2-5 years changed to pale brown.

ANTENNAE (Fig. 76D): Very long and slender, reaching to body ring 7 or 8 (male), and 6 (female) when stretched dorsally.

COLLUM (Fig. 76A): With 3 transverse rows of setiferous tubercles, 4+4 anterior, 1+1 intermediate and 2+2 posterior tubercles, lateral tubercles of posterior row located almost halfway anteriad to intermediate row; paraterga with one conspicuous setiferous notch on lateral margin, elevated at 15°-20°.

TEGUMENT: Slightly shining; collum and metaterga coarsely microgranulate; surface below paraterga finely microgranulate; prozona finely shagreened; paraterga, sterna and epiproct smooth.

METATERGA (Fig. 76 A–C): With 2 transverse rows of setiferous rose thorn-like spines; metaterga 2-18 with 2+2 anterior and 2+2 posterior spines; metatergum 19 with 2+2 anterior and 2+2 posterior spines/tubercles.

PARATERGA (Fig. 76E, F): Directed caudolaterad on body rings 2-17, elevated at ca. 45° (male) 40° (female); directed increasingly caudad on body rings 18 and 19; anterior margin with 2 distinct notches, on lateral margin of body rings 9, 10, 12, 13, 15-18 with tiny denticle near the tip.

TELSON (Fig. 77 C–G): Epiproct: tip slightly or moderately concave; lateral setiferous tubercles inconspicuous, short; apical tubercles conspicuous, usually short (very long and distinct in Kanchanaburi B population). Hypoproct trapeziform; caudal margin round, with inconspicuous setiferous tubercles.

STERNA (Fig. 78): Cross-impressions shallow. Sternal lobe between male coxae 4 swollen and stout, usually trapeziform (in specimen from Lamphun Province subsemicircular), tip usually round or truncate (in some specimens slightly emarginate).

LEGS (Fig. 77 H–J): Very long and slender. Male femora 5 and 6 strongly humped ventrally in middle part.

GONOPODS (Figs 79, 80, 81): Coxa (cx) longer than prefemur. Cannula (ca) long and slender. Prefemur (pfe) ca. 2/3 as long as femur. Femur (fe) long and slender. Mesal sulcus (ms) very deep and wide, lateral sulcus (ls) very deep, long and narrow. Postfemur (pof) conspicuous, ventrally very wide and stout. Solenophore (sph) well-developed: lamina lateralis (ll) swollen, surface smooth; ventral lobe (vll) long and slender, digitiform, tip round, directed ventrad: lamina medialis (lm) well-developed; process (plm) very long, spine-like, tip usually bifurcating into two distinct spines (in some populations tip terminating in 3-5 spines), directed mesoanteriad; distal lobe (dlm) quite long, distally with two distinct lamellae (mesal lamella slightly smaller than lateral one, tip crenate; lateral lamella broad); broad lobe (blm) thick, obviously demarcated from distal lobe (dlm) by conspicuous indentation. Solenomere (sl) long, twisted distally.

Distribution and habitat.

Known from several places in many provinces (Kampaeng Phet, Kanchanaburi, Lamphun, Suphan Buri, and Uthai Thani). All specimens were collected from limestone habitats (Fig. 75E); they were very easy to collect because of their aposematic colouration. We noticed that August–September is an annual peak period for adult swarming.

Although this species has been found in several places, it is distributed only in central, west, and north Thailand. Hence, D. purpurosea is regarded as endemic for the Thai fauna.

A specimen from Nakhon Sawan Province (Mae Wong National Park, near the type locality of D. purpurosea ) which really looks very much like D. purpurosea is shown on YouTube ("shocking pink dragon millipede - living treasure of the forest at Mae Wong National Park" (https://youtu.be/jQsn6rOrlA8 - in Thai)). Although we cannot confirm this record because we did not examine specimens from this location, according to the known distribution of D. purpurosea , the specimen from Nakhon Sawan Province may possibly be this species.

Remarks.

Interestingly, all adult specimens in all populations show exactly the same colour as reported in the original description: vivid pink to purple. However, we found morphological variation between four main populations delimited as follows:

1. Lamphun - Tham Erawan.

2. Uthai Thani - Tham Pha Nam Thip, Wat Wang Pong, Wat Khao Chuak Charoen Tham, Wat Tham Khao Wong and Tham Weruwan.

3. Kanchanaburi A - Tham Than Lod Cave.

4. Kanchanaburi B - Daowadueng Cave, Ban Thung Kang Yang, Wat Sunantha Wanaram, Kroeng Krawia Waterfall and Kroeng Krawia Checkpoint.

- Size: Specimens from the Lamphun and Uthai Thani populations are larger than others (length 28-34 mm in male, 32-38 mm in female), whereas specimens from the Kanchanaburi B population seems to be smaller than others (length 22-26 mm in male, 26-28 mm).

- Sternal lobe between male coxae 4: The only studied specimen from the Lamphun population has a subsemicircular and quite short lobe, while in others the lobe is trapeziform.

- Apical tubercles of epiproct: Distinctly longer in the Kanchanaburi B population than in others.

- Process (plm) of lamina lateralis: A bifurcate tip, as two conspicuous spines, in the Lamphun and Uthai Thani populations, but terminating in several spines in the Kanchanaburi A and B populations.

The shape of the hypoproct varies within populations: in some specimens it is trapeziform, in others it is subsemicircular.

D. purpurosea shares some morphological characters with D. breviverpa and D. takensis , viz., metaterga 9-19 with rows of 2+2 (anterior) and 3+3 (posterior) setiferous tubercles/cones/spines. However, the differences in gonopod characters are sufficient for separating these as different species.

Coexisting species.

Desmoxytes octoconigera sp. n. and D. golovatchi sp. n. (see details under these species).