Hylomus piccolo Nguyen, Vu & Nguyen, 2025, sp. nov.

Hylomus piccolo sp. nov. Figs 1, 2, 3, 4 Material examined. Holotype. Vietnam • 1 male; Cao Bang Province, Pia Oac-Pia Den National Park; 22.5943 ° N, 105.8846 ° E; 1200 m a. s. l.; 9 May 2021; Anh D. Nguyen leg.; bushes; IEBR-Myr 904 H. Paratypes. Vietnam • 10 males, 5 females; same data as for holotype; EBR-Myr 904 P • 1 male, 1 female; same data as for holotype; IEBR-Myr 901. Diagnosis. The species can be discriminated from the congeners by the presence of long spiniform paraterga, midbody metaterga with only two rows of 1 + 1 small setiferous spines in the middle and 2 + 2 longer setiferous spines near posterior margin; male femora 6 with a large tubercle ventrally; sternite 5 with a large, sparsely setose, bifid, trapeziform lamina between male coxae 4; epiproct without conspicuous setiferous knobs near tip; gonopod lamina lateralis broadly rounded, partly folded to sheathe distal part of solenomere; gonopod lamina medialis with a small rounded lobe at middle. The new species is similar to Hylomus namek Nguyen et al., 2019 but differs from this species by the following characters: the ventral side of male femora 6 with a big, robust tubercle in the middle (vs. femora 6 and 7 with large tubercles); longer spiniform paraterga; and gonopod lamina medialis with a small rounded lobe in the middle (vs. without processes). Etymology. The name refers to “ piccolo ”, a main character of the Japanese manga “ Dragon balls ” by Toriyama Akira (Japan). Noun in apposition. Description. Length c. 11.6–12.8 mm (male), 13.9–15.2 mm (female); width of midbody pro- and metazona (distance between two paratergal tips) 0.6–0.8 mm (male), 1.12–1.25 mm (female) and 3.1–3.3 mm (male), 3.4–3.6 mm (female), respectively. Holotype length c. 11.8 mm, width of midbody pro- and metazona 0.74 mm and 3.2 mm, respectively. Coloration: Generally darkish-red to darkish-brown except paraterga, sterna, legs whitish-yellow; distal part of main branch pinkish. Head (Fig. 1 A – C): Clypeolabral region densely setose, vertex sparsely setose. Epicranial suture distinct, dividing frons into two equal parts; with setae along the suture. Antenna slender, extremely long, reaching back to body ring 7 if stretched along the body axis; antennomere 1 <7 <6 <2 <3 = 4 = 5 in length. Collum (Fig. 1 C): Slightly narrower than head; surface dull, coarsely microgranulate; with two rows of spines: 3 + 3 spines in anterior row and 2 + 2 spines in posterior row. Paraterga of collum well developed, spiniform; directed dorsad; highly elevated above dorsal surface; with two conspicuous teeth on anterior side. Body rings: Ring 3 <4 <2 = 5–16 in width, thereafter gradually tapering towards telson. Prozona finely shagreened; metazona and pleura with microgranulations. Transverse sulcus present, but inconspicuous on metaterga 5–18. Axial line missing. Metaterga with two rows of 1 + 1 smaller setiferous spines in middle and 2 + 2 longer setiferous spines near posterior margin (Fig. 2 B). Suture between pro- and metazona broad, very shallow. Pleurosternal carinae present as a complete keel on body rings 2–3, then missing on subsequent body rings. Paraterga (Figs 1, 2): Very well developed; directed dorsad; long and spiniform with a large branch and 2–3 tiny teeth on anterior side (2 on poreless body rings and 3 on pore-bearing rings) and with 1 larger spine on posterior side. Paratergum on ring 19 directed caudad. Ozopore located between the second tooth and main branch of paraterga, visible in dorsal view. Telson (Fig. 3 A, B): Epiproct without conspicuous setiferous knobs near tip, but broadly truncated; tip with four spinnerets; lateral tubercles well developed (Fig. 3 A). Hypoproct subtrapeziform, with two distolateral, completely separated, setiferous knobs (Fig. 3 B). Legs: Extremely long, slender and thin, c. 1.8–2.0 times as long as midbody height. Prefemora not swollen. Male femora 6 each ventrally with a large, robust tubercle in middle (Figs 1 A, 3 C). Sterna: With distinct cross-impressions, no modification – except a large, sparsely setose, bifid, trapeziform lamina between male coxae 4 (Figs 1 A, 3 D). Gonopod (Fig. 4): Suberect. Coxite (co) cylindrical, larger than femorite, sparsely setose distodorsally. Prefemorite (pref) densely setose, equal to femorite as well. Femorite (fe) slightly enlarged distad (from ventral view); without a demarcation with postfemoral region. Postfemoral region inconspicuous. Solenophore (sph) well developed; lamina lateralis (ll) broadly rounded, partly folded to sheathe distal part of solenomere; lamina medialis (lm) with a small rounded lobe at about midway. Seminal groove running entirely on mesal side, then entering a flagelliform solenomere (sl), solenomere partly sheathed by solenophore. Tip of solenophore rounded. DNA barcoding. (Appendix 1) A fragment of the COI gene is accessioned at NCBI GenBank with the following accession number PQ 676351. The new species exhibits a COI gene similarity of 86.22 % and 86.57 % (OR 765910 and MG 669370, respectively) identity with Hylomus cervarius (Attems, 1953).