Pseudodesmus bidoup, Nguyen & Nguyen & Korsós, 2024

Nguyen, Anh D., Nguyen, Lien T. P. & Korsós, Zoltán, 2024, A review of the millipede genus Pseudodesmus Pocock, 1887 (Diplopoda, Platydesmida, Andrognathidae) from Vietnam, with descriptions of five new species and notes on its phylogeny, Zoosystematics and Evolution 100 (4), pp. 1515-1541 : 1515-1541

publication ID	https://doi.org/ 10.3897/zse.100.132111
publication LSID	lsid:zoobank.org:pub:B39508EB-6EB2-4CC0-88D8-B3E87BDCED02
DOI	https://doi.org/10.5281/zenodo.14052222
persistent identifier	https://treatment.plazi.org/id/0E9D217B-0ED9-41E8-9712-960188EF700A
taxon LSID	lsid:zoobank.org:act:0E9D217B-0ED9-41E8-9712-960188EF700A
treatment provided by	Zoosystematics and Evolution by Pensoft
scientific name	Pseudodesmus bidoup
status	sp. nov.

Treatment

Pseudodesmus bidoup sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5

Type material.

Holotype. Vietnam • 1 male; Lam Dong Province, Bi Doup – Nui Ba National Park ; 12.11231 ° N, 108.6627 ° E; 1,500–1,800 m a. s. l.; 29 April – 9 May 2009; Anh D. Nguyen leg; mixed forest; IEBR-Myr 957 H . GoogleMaps

Paratypes. Vietnam • 1 female, 1 juvenile; same data as for the holotype; IEBR-Myr 957 P GoogleMaps • 1 female; same data as for the holotype; HNHM GoogleMaps • 1 male (41 body rings); Kon Tum Province, Lo Xo pass ; 15.23439 ° N, 107.73386 ° E; 830 m a. s. l.; 15–19 April 2004; Anh D. Nguyen leg.; secondary forest; pitfall trap; IEBR-Myr 961 GoogleMaps .

Diagnosis.

Head slightly smaller than collum. Collum with two rows of tubercles 1 + 1 (2) smaller and 2 + 2 larger tubercles. Body smooth, neither setose nor pubescent, midbody rings with two rows of tubercles on metazonites, anterior row longer, extending to about midlength of paraterga, containing 5 + 5 tubercles; posterior row shorter and extending to base of paraterga, consisting of 3 + 3 tubercles. Posterior gonopods 6 - segmented, distally carrying four apical stylets.

Diagnosis remark.

The new species is easily distinguished from P. camptotrichus by coloration in alcohol (light yellowish vs earth brown). It also differs from two previously known species, P. variegatus and P. camptotrichus in having smaller size (number of male body rings: 35 vs 53–56 and 37–42; length: 9.25 mm vs 32 mm and 14 mm; width: 1.63 mm vs 5.8 mm and 2.0 mm, respectively), number of metazonal tubercles (two rows of 5 + 5 and 3 + 3 vs two rows of 8–15 + 8 – 15 and 5–7 + 5 – 7, and two rows of 6 + 6 to 9 + 9 each row, respectively).

Description.

Male holotype.

Measurements: 35 body rings plus telson; length about 9.25 mm, length of metazona about 0.19 mm, width of metazona about 1.63 mm, width of prozona about 1.25 mm; ratio of width of head and width of collum = 0.93.

Coloration of ethanol-preserved specimen: whole body including legs and antenna light yellowish.

Head almost smooth, not setose, round-shaped. Antenna stout, clavate, in situ extending to body ring 4; antennomere 6> 5> 3> 4 = 2> 7 = 1 in length. Collum with distinct, but small paraterga directed anterolaterad (Figs 2 B View Figure 2 , 3 A View Figure 3 ); two rows of tubercles on collum: anterior row with 1 + 1 small tubercles, posterior row with 2 + 2 large tubercles including larger paramedian ones (Fig. 3 A View Figure 3 ). Body smooth, neither setose nor pubescent. Metatergites elevated medially and slightly declined laterad, so body in cross-section subtriangular. Terga 2–4 with a row of 2–4 + 2 – 4 large tubercles including 2 + 2 tubercles on paraterga (Figs 2 B View Figure 2 , 3 A View Figure 3 ); other terga with two rows of tubercles, anterior row longer, extending to about midlength of paraterga, containing 5 + 5 tubercles; posterior row shorter and extending to base of paraterga, consisting of 3–4 + 3 – 4 tubercles. Paramedian tubercles considerably larger (Figs 2 A – C View Figure 2 , 3 A, B View Figure 3 ).

Paraterga slightly curved anteriad on body rings 2–5, lateral margins rounded (Fig. 2 A, B View Figure 2 ); increasingly less so curved the following body rings, slightly curved caudad on body rings 25–27, and strongly curved caudad on body rings 28–31; caudal corners of paraterga increasingly acute on 6–7 posteriormost body rings in front of telson; paraterga of penultimate body ring produced strongly caudad and flanking telson (Figs 2 A – C View Figure 2 , 3 A, B View Figure 3 ). All margins of paraterga serrated, with tiny setae.

Telson (Figs 2 C View Figure 2 , 3 D View Figure 3 ) short, caudal margin rounded; epiproct with 2 + 2 small / tiny tubercles at caudal margin. Paraprocts and hypoproct semi-circular.

Legs slender, shorter than mid-metazonal width, terminating before lateral margins of paraterga. Prefemur = tarsus> femur> postfemur = tibia in length. Claws normal. Coxal sacs present from body rings 3–28 (Fig. 3 D View Figure 3 ).

Gonopods: Two pairs of gonopods directed anteromesad. Anterior gonopods (Figs 4 A View Figure 4 , 5 A, B View Figure 5 ) 6 - segmented, covered with long setae; coxite broad, basal part sparsely covered with microgranulations; podomere 3 and ultimate podomere (po 6) longest; ultimate podomere with distal long, thick setae (mse). Posterior gonopods (Figs 3 B View Figure 3 , 4 C, D View Figure 4 ) 6 - segmented, covered with sparse long setae; coxite broadly large, basal part sparsely covered with microgranulations; podomeres 2–5 short and stout, somewhat equal in length; ultimate podomere (po 6) longest, with four apical stylets (sty).

Variation.

Female paratype: number of body rings 43–44 plus telson, length ca. 13.75–14.50 mm, length of midbody metazonites about 0.27–0.31 mm, width of midbody metazonite and prozonite ca. 2.25–2.50 mm and 1.56–1.63 mm, respectively; ratio of width of head and width of collum = 0.96. Nonsexual characters as in male.

The male sample IEBR-Myr 961 has strong tubercles, even on the collum, then on every body ring the two (1 + 1) median posterior tubercles form a strong paramedian crest along the entire body. Anterior tubercles are also the same but smaller. Color is uniformly yellowish, without a dark pattern.

Etymology.

Named after the “ Bi Doup ” mountain, type locality. Noun in apposition.

Distribution.

The species has been found in mixed forests and regenerated forests in Kon Tum and Lam Dong provinces, Highlands of Vietnam.

DNA barcoding.

Sequencing a fragment of the COI gene failed.