Desmoxytes taurina (Pocock, 1895)

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

publication ID

http://dx.doi.org/10.3897/zookeys.761.24214

publication LSID

lsid:zoobank.org:pub:91658359-00AE-4319-ACBC-E9C544599C5B

persistent identifier

http://treatment.plazi.org/id/CA489631-CFC2-034C-7BB0-7F0275F1DC47

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ZooKeys by Pensoft

scientific name

Desmoxytes taurina (Pocock, 1895)
status

 

Desmoxytes taurina (Pocock, 1895)  Figs 84, 85, 86, 87

Prionopeltis taurinus  Pocock, 1895: 830. Attems 1914: 204. Weidner 1960: 89. Jeekel 1965: 124.

Pratinus taurinus  - Attems 1937: 121. Jeekel 1964: 63; 1968: 61.

Desmoxytes taurina  - Jeekel 1980a: 655. Golovatch and Enghoff 1994: 57. Nguyen and Sierwald 2013: 1243. Likhitrakarn et al. 2017: 20.

Material examined.

Lectotype. Male (rings 1-11 only, with gonopod - pinned through body) (ZMUC), MYANMAR, Pegu (Taikkyii and Palon), leg. Fea. Lectotype here designated.

Paralectotypes. 1 male (2-3 broken rings in very poor condition, without gonopods) (ZMUC), MYANMAR, Pegu (Taikkyii and Palon), leg. Fea. 2 females (1 female, complete - pinned through body; 1 female, remaining rings 11-20 - pinned through body) (NHMUK), MYANMAR, Rangoon, leg. E. W. Oates [Yangon].

Diagnosis.

Metaterga 9-19 usually with 2+2 cones/spines (anterior row) and 3+3 cones/spines (posterior row). Similar in this respect to D. breviverpa  , D. purpurosea  and D. takensis  . Differs from these species by the following combination of characters; process (plm) of lamina medialis short, thick and broad, directed mesad, tip blunt; distal lobe (dlm) apically with two distinct lamellae, mesal and lateral lamellae equal in size, very broad and thick; epiproct short; male femora 5 and 6 slightly humped ventrally.

Type locality.

Myanmar, Pegu (Taikkyii and Palon).

Redescription.

SIZE: Length ca. 23 mm (male), ca. 27 mm (female) width of midbody metazona ca. 1.7 mm (male), 2.3 mm (female). Width of head < collum < body ring 2 < 3 = 4 < 5-16, thereafter body gradually tapering toward telson.

COLOUR: In life with body probably brownish black (Pocock, 1895) or castaneous brown? (Golovatch and Enghoff, 1994). Colour in alcohol: after ca. 100 years changed to pale brown (lectotype) or rusty brown (paralectotypes).

ANTENNAE (Fig. 84D): Long and slender, probably reaching to body ring 5 (male) and 4-5 (female) when stretched dorsally.

COLLUM (Fig. 84A): With 3 transverse rows of setiferous tubercles, 4+4 anterior, 1+1 intermediate and 2+2 posterior tubercles (lateral tubercles of anterior row located near base of paraterga); paraterga of collum low, elevated almost in horizontal plane, directed caudolaterad, with one inconspicuous notch on lateral margin.

TEGUMENT: Quite dull; collum and metaterga coarsely microgranulate; prozona finely shagreened; surface below paraterga and sterna finely microgranulate; paraterga and epiproct smooth.

METATERGA (Fig. 84 A–C): With 2 transverse rows of setiferous tubercles and setiferous cones; metaterga 2-8 with 2+2 anterior and 2(3)+2(3) posterior cones; metaterga 9-18 with 2+2 anterior and 3(2)+3(2) posterior cones (anterior cones shorter than posterior ones); metatergum 19 with 2+2 anterior and 3+3 posterior tubercles.

PARATERGA (Fig. 84E, F): Directed caudolaterad on body rings 2-17, elevated at ca. 50° (male) 45° (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. 85 C–G): Epiproct short; tip truncate; lateral setiferous tubercles and apical tubercles inconspicuous. Hypoproct subtrapeziform; caudal margin round, with inconspicuous setiferous tubercles.

STERNA (Fig. 86): Cross-impressions shallow. Sternal lobe between male coxae 4 swollen, stout, subquadrate when seen in caudal view; base enlarged, slightly attenuated near tip; tip slightly emarginate.

LEGS (Fig. 85 H–J): Very long and slender. Male femora 5 and 6 slightly humped ventrally in middle part.

GONOPODS (Fig. 87): Coxa (cx) longer than prefemur. Cannula (ca) slender. Prefemur (pfe) ca. 2/3 as long as femur. Femur (fe) long and slender. Mesal sulcus (ms) and lateral sulcus (ls) very deep. Postfemur (pof) conspicuous, ventrally wide. Solenophore (sph) well-developed: lamina lateralis (ll) swollen, stout: lamina medialis (lm) well-developed; process (plm) slightly short, thick and broad, directed mesad, tip blunt; distal lobe (dlm) well-developed, distally with two distinct lamellae (mesal lamella and lateral lamella equal in size, very broad and thick); broad lobe (blm) very thick, distinctly demarcated from distal lobe (dlm) by a conspicuous, shallow indentation. Solenomere (sl) quite long.

Distribution and habitat.

This species is known from Myanmar - Rangoon and Pegu (Taikkyii and Palon). [Rangoon is currently Yangon. Pegu is presently Bago township (Hanthawaddy), Bago region. Taikkyii is Taikkyi township, Yangon region. Palon is probably a small village located in the area north to Taikkyii in the west of Pegu, Yangon region]. Taikkyii and Palon were formerly parts of Pegu region, now they belong to Yangon region. Therefore, the label of specimens collected by Fea gives the locality as Pegu (Taikkyii and Palon).

Habitat details for this species have never been reported; however, all locations are supposed to be granitic and limestone mountain ranges based on geological data, and the two locations were approximately 20 km apart.

We assume that D. taurina  is distributed in a narrow range. A field survey near Yangon in 2015 revealed no further specimens of D. taurina  . Therefore, we regard this species as endemic to Myanmar.

Note on material.

In the original description Pocock (1895), wrote that all specimens were collected from Rangoon by Oates and from Pegu (Taikkyii and Palon) by Fea. Two females collected by Oates are now in NHMUK, one specimen collected by Fea in ZMH and two males collected by Fea in ZMUC.

The two males in ZMUC collected by Fea are labelled “cotypes”, and only “Palon” is given as locality whereas in the original description Pocock gave "Pegu (Taikkyii and Palon)". We assume that these two males were probably collected from different locations, one from Taikkyii and one from Palon.

Weidner (1960) classified a specimen (unknown sex, not studied by us) of Prionopeltis taurinus  (= Desmoxytes taurina  ) in ZMH as a “paratypoid”. However, Pocock (1895) and the following authors did not designate a holotype or lectotype for this species, thus, all specimens are syntypes.

The lectotype chosen is the ZMUC male with one remaining gonopod. The other ZMUC, ZMH and NHMUK specimens are designated here as paralectotypes.

Colour of type specimens: the lectotype is brown without metallic oxidation of the pin while the paralectotypes in NHMUK have become greenish black with metallic oxidation of the pin.

Remarks.

This species has not been revised since Golovatch and Enghoff gave a good description in 1994. Golovatch and Enghoff (1994) described the collum with rows of 3(4?)+3(4?) anterior tubercles, suture between prozona and metazona distinctly beaded, pleurosternal carinae absent. After examining all known specimens except the one in ZMH, we found:

- collum with rows of 4+4 anterior tubercles (lateral tubercles near base of paraterga).

- suture between prozona and metazona not beaded, but with very small ridges of irregular shape.

- pleurosternal carinae of all specimens conspicuously present on body ring 2, very small ridges on body ring 3, thereafter missing.

We noticed that the number of cones (posterior row) on metaterga varies between individuals. Most specimens have metaterga 8 with 2+2 tubercles in the posterior row, but some have 3+2 tubercles. Metaterga 9-19 usually have 3+3 tubercles in the posterior row, whereas some individuals have with 3+4 or 4+3 tubercles.

The length of antenna in male could not be examined (antennae missing in both males), but the antennae are supposed to reach to ring 5 ( Pocock 1895).

Coexisting species.

None known.