Limbodessus juliana, Balke & Villastrigo & Hájek & Surbakti & Panjaitan & Hendrich, 2025

Balke, Michael, Villastrigo, Adrián, Hájek, Jiří, Surbakti, Suriani, Panjaitan, Rawati & Hendrich, Lars, 2025, A review of Limbodessus Guignot, 1939 from New Guinea, with description of eight new tropical-alpine species (Coleoptera, Dytiscidae, Bidessini), Alpine Entomology 9, pp. 5-28 : 5-28

publication ID	https://doi.org/10.3897/alpento.9.147831
publication LSID	lsid:zoobank.org:pub:15F39A4A-E56E-41F1-860B-90B05ABF06E8
DOI	https://doi.org/10.5281/zenodo.15602650
persistent identifier	https://treatment.plazi.org/id/62D5454A-FE1D-5597-A65B-5693F92DD276
treatment provided by	Alpine Entomology by Pensoft
scientific name	Limbodessus juliana
status	sp. nov.

Treatment

Limbodessus juliana sp. nov.

Figs 4 A View Figure 4 , 7 D View Figure 7 , 9 D View Figure 9 , 10 E, I View Figure 10 , 11 E View Figure 11 , 13 H View Figure 13 , 14 View Figure 14 , 17 F, G View Figure 17 , 18 A, B View Figure 18

Type locality.

Mossy puddles in Alpine grassland, Mt. Juliana area GoogleMaps , Sab-me Valley, 3,400–3,500 m [140°17'E, 04°27'S], Papua, Indonesia.

Type material.

Holotype, male: “ IRIAN JAYA, Mt. Juliana Gebiet, 16. - 17. 9. 1993, Sab-me Tal , 3400–3500 m, ca. 140°17'E 04°27'S, leg. M. Balke (14) ”, “ Holotype Limbodessus juliana sp. nov. Balke et al. 2025 ” [red printed label] ( NHMW) GoogleMaps .

Paratypes (573): 169 exs., with the same label data as the holotype GoogleMaps ; 19 exs., “ IRIAN JAYA: Aipomek Area [N Pass] Aipomek-Langda , 140°05'E 04°27'S, 22. - 24. 8. 1992, 3550–3600 m, leg. M. Balke (20) ” [IR 92 # 20] ( MZB, NHMW, KSP, ZSM) GoogleMaps ; 216 exs., “ IRIAN JAYA: Aipomek Area [N Pass] Aipomek-Langda , 140°06'E 04°27'S, 22. - 24. 8. 1992, 3550–3600 m, leg. M. Balke (21) ” [IR 92 # 21] ( NHMW, KSP, ZSM) GoogleMaps ; 136 exs., “ IRIAN JAYA: Aipomek Area [N Pass] Aipomek-Langda , 140°05'E 04°27'S, 22. - 24. 8. 1992, 3550–3600 m, leg. M. Balke (20–22) ” [IR 92 # 20-22] ( NHMW, KSP, ZSM) GoogleMaps ; 3 exs., “ IRIAN JAYA: Aipomek Area [South Pass], 140°06'E 04°27'S, 27. 8. 1992, 3500 m, Aipomek-Langda , leg. Balke (26) ” ( NHMW, ZSM) GoogleMaps ; 24 exs., “ IRIAN JAYA: Aipomek Area [N Pass], 140°05'E 04°27'S, 22. - 24. 8. 1992, 3800 m, Aipomek-Langda , leg. Balke (26) ” [IR 92 # 26] ( NHMW, KSP, ZSM) GoogleMaps ; 6 exs., “ W. Neuguinea, Pass nach Langda , 3900 m, vi. 1979, P. Blum leg. ” ( ZSM) . All paratypes are provided with a red printed paratype label.

Measurements.

Holotype: TL = 2.6 mm; TL-H = 2.3 mm; MW = 1.2 mm. Paratypes: TL = 2.6–2.7 mm, TL-H = 2.4–2.5 mm, MW = 1.1–1.5 mm.

Description.

Body rather elongate-oval, with distinct discontinuity in lateral outline between pronotum and elytron; apically broadly rounded to truncate. No cervical or sutural line. Pronotal stria present and distinct, no elytral stria visible (Fig. 4 A View Figure 4 ).

Color. Body chiefly black. Clypeus anteriorly, pronotum anteriorly and laterally slightly paler: dark castaneous brown. Antenna chiefly blackish. Legs dark castaneous brown (Fig. 4 A View Figure 4 ). Ventral side chiefly black, sternite 7 dark ferruginous.

Note: The first author also collected / observed paler specimens which appear mature. The body is then castaneous brown to dark ferruginous, elytron sometimes darker medially.

Sculpture. Head moderately densely punctate; punctation on clypeus and apically sparser; microreticulate. Punctures of same size as meshes of microreticulation. Pronotum with moderately dense punctation along fore-margin; rest sparsely punctate especially on disc. Size of punctures as on head; discally distinctly smaller. Elytron with moderately dense and evenly distributed punctation; between punctures with almost invisible larger polygonal meshes. Ventral side with few punctures, shiny; only sternite 7 with distinct microreticulation.

Structures. Metacoxal lines slightly diverge anteriorly and do not reach posterior margin of metaventrite; with concavity between lines.

Male. Pronotum and elytra shiny, without mircoreticulation. Antenna stout (Fig. 13 H View Figure 13 ). Median lobe as in Fig. 7 D View Figure 7 and parameres as in Figs 10 E, I View Figure 10 , 11 E View Figure 11 .

Female. Pronotum and elytron dull, with distinct microreticulation between punctures. Antenna stout but without conspicuous modifications (Fig. 13 H View Figure 13 ).

Etymology.

The name refers to Mount Juliana (Fig. 18 B View Figure 18 ), one of the localities of this species. The name is a noun in the nominative standing in apposition.

Distribution.

Only know from the type locality, Sab-me Valley below Mt. Orom, Papua (Fig. 14 View Figure 14 ).

Differential diagnosis.

The new species belongs to a group of larger (TL = 2.25–3.0 mm) and almost blackish high alpine species. L. juliana sp. nov. is close to L. alexanderi and L. habbema sp. nov. but can be separated from them by the form of the female antennae, which is stout without any conspicuous modifications (Fig. 13 H View Figure 13 ), the form of the median lobe (Fig. 7 D View Figure 7 ), and the form of the parameres (Figs 10 E View Figure 10 , 11 E View Figure 11 ).