Liodessus rhigos, Balke & Megna & Zenteno & Figueroa & Hendrich, 2020

Balke, Michael, Megna, Yoandri S., Zenteno, Nilver, Figueroa, Luis & Hendrich, Lars, 2020, New Liodessus species from the high Andes of Peru (Coleoptera: Dytiscidae Bidessini), Zootaxa 4852 (2), pp. 151-165 : 156-157

publication ID	https://doi.org/ 10.11646/zootaxa.4852.2.1
publication LSID	lsid:zoobank.org:pub:2A612C28-2E39-4729-9DDD-27EE6ED90F4E
DOI	https://doi.org/10.5281/zenodo.4519039
persistent identifier	https://treatment.plazi.org/id/03EDDF2B-FFC3-F21B-FF0C-FB3B19F8FDFB
treatment provided by	Plazi
scientific name	Liodessus rhigos
status	sp. nov.

Treatment

Liodessus rhigos View in CoL sp. nov.

( Figs 2C, D View FIGURE 2 , 4D View FIGURE 4 , 5D, F View FIGURE 5 )

Type locality. Peru: Junín, Junín, Lagoon Huacra , 4,461 m , -11.289° -76.007°.

Type material. Holotype: Male ( MUSM): “ Peru: Junín, Junín, Lagoon Huacra, 4461 m, 14.viii.2018, -11.289° -76.007°, Y. S. Megna & N. Zenteno ( PER _YSM_2018_13)”; “ Holotype Liodessus rhigos sp. nov. Balke, Megna, Hendrich des. 2020” [red printed label].

24 Paratypes ( MUSM, ZSM) : 22 exs.: same data as holotype ; 1 exs.: “ Peru: Junín, Junín, Lagoon Yanamyacu , 4327 m, 14.viii.2018, -11.314° -75.956°, Y. S. Megna & N. Zenteno. ( PER _YSM_2018_16)”. All paratypes are provided with our red printed paratype labels .

Description of holotype. Habitus with indistinct discontinuity between pronotum and elytra; appearing less pear shaped than other species (as in Figs 2C, D View FIGURE 2 ). TL: 2.1 mm; TL-H: 1.8 mm; TW: 0.9 mm.

Colouration. Mostly blackish dorsally and ventrally (as in Figs 2C, D View FIGURE 2 ).

Surface sculpture. Head with faint microreticulation except on frons and with few fine setiferous punctures; pronotum shiny with with sparser and fine setiferous punctation; elytra shiny with moderately dense and fine setiferous punctation (as in Fig. 2C View FIGURE 2 ).

Structures. Antenna stout. Head with faint cervical line. Pronotum on each lateral side (or margin) with distinct bead and with distinct and deep basal plicae. Elytron without basal striae. Metathoracic wings short, slightly longer than half the length of elytron.

Genitalia. Median lobe of aedeagus thin and evenly curved in lateral view, apex moderately thin, apex in ventral view more strongly narrowing and pointed; lateral lobes (parameres) with distal part longish ( Fig. 4D View FIGURE 4 ).

Variation. TL: 2.0– 2.1 mm; TL-H: 1.6–1.8 mm; TW: 0.9–1.0 mm. Few specimens with cervical line extremely faint and interrupted. We assessed the length of the metathoracic wings in 10 specimens, which all had the same short wing length. While these specimens are certainly not able to fly actively, there might be few fully winged individuals that are capable of flight.

Female. Dorsal surface dull due to presence of distinct microreticulation ( Fig. 2D View FIGURE 2 ).

BOLD platform. We provided 3 entries in the “COLLI” project, all retrieved in one cluster. Assignment to that cluster was unambiguous, meaning all specimens were correctly assigned to this morphologically delineated species.

Etymology. From the Greek rhigos (cold) referring to the chilly collecting experience. The name is a noun standing in apposition.

Distribution. Known from the type locality in the high Andes of central Peru ( Fig. 7 View FIGURE 7 ), ca. 4,300 –4,500 m.

Habitat. Shallow and exposed puddles, collected with strainer out of mats of vegetation ( Fig. 5D View FIGURE 5 ). Other Dytiscidae associated with this species were species of Rhantus Dejean, 1833 and Lancetes Sharp, 1882 , as well as Liodessus acollensis .