Pseudodesmus bidoup Nguyen, Nguyen & Korsós, 2024, sp. nov.
Creators: name: Nguyen, Anh D.
name: Nguyen, Lien T. P.
name: Korsós, Zoltán
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Diplopoda
Platydesmida
Andrognathidae
Pseudodesmus
Pseudodesmus bidoup

description: Pseudodesmus bidoup sp. nov.
Figs 2, 3, 4, 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.
Paratypes. Vietnam • 1 female, 1 juvenile; same data as for the holotype; IEBR-Myr 957 P • 1 female; same data as for the holotype; HNHM • 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.
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, 3 A); 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). 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, 3 A); 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, 3 A, B).
Paraterga slightly curved anteriad on body rings 2–5, lateral margins rounded (Fig. 2 A, B); 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, 3 A, B). All margins of paraterga serrated, with tiny setae.
Telson (Figs 2 C, 3 D) 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).
Gonopods: Two pairs of gonopods directed anteromesad. Anterior gonopods (Figs 4 A, 5 A, B) 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, 4 C, D) 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.
description: Published as part of 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, pp. 1515-1541 in Zoosystematics and Evolution 100 (4) on pages 1515-1541, DOI: 10.3897/zse.100.132111