Liodessus bogotensis matarredonda, Balke & Neven & Villastrigo & Ospina-Torres & Prieto & Gutierrez Rubiano & Lotta & Dueñas & Hendrich, 2023

Balke, Michael, Neven, Katja, Villastrigo, Adrian, Ospina-Torres, Rodulfo, Prieto, Carlos, Gutierrez Rubiano, Nicolas, Lotta, Ingrid, Duenas, Luisa F. & Hendrich, Lars, 2023, Eastern Colombian Paramo Liodessus Guignot, 1939 diving beetles are genetically structured, but show signs of hybridization, with description of new species and subspecies (Coleoptera, Dytiscidae), ZooKeys 1143, pp. 165-187 : 165

Liodessus bogotensis matarredonda ssp. nov.

Figs 6A , 9B , 10E

Type locality.

Colombia, Cundinamarca, Páramo de Matarredonda.

Holotype: Colombia • ♂; Cundinamarca, Matarredonda park; 3,400 m alt.; 20.xi.2018; 4.560, -74.013; Ospina, Balke & Megna leg.; COL_MB_2018_10; UNAL. Paratypes: Colombia • 126 specimens; same data as holotype; UNAL, ZSM. ZSM specimen imaging number for holotype: ZSM-COL-00084.

Description of holotype.

Habitus narrowly elongate-oval, with a slight discontinuity between pronotum and elytra (Fig. 6A ); pronotum widest before base (Fig. 6A ). Total length 2.0 mm; length without head 1.8 mm; maximum width 0.9 mm.

Color. Very dark brown to blackish dorsally and ventrally; lighter on anterior head, lateral pronotum, and bases of meso- and metatibia; elytron with slightly paler band like markings obvious under dorsal lighting under dissecting scope. (Fig. 6A ).

Surface sculpture. Head with a few setiferous punctures in front of a faint occipital line, distinct microreticulation present except on middle of head between the eyes (Fig. 6A ); posterior to occipital line with distinct microreticulation and few punctures. Pronotum and elytron shiny, with moderately dense, coarse, setiferous punctation (Fig. 6A ).

Structures. Head with faint occipital line, with rounded clypeus. Antenna stout. Pronotum with distinct lateral bead and distinct, long, deep basal striae (Fig. 6A ).

Genitalia. Median lobe of aedeagus typical of the L. bogotensis complex, with slight variation in curvature among individuals, somewhat more bulbous before tip; tip in ventral view more parallel-sided (Figs 9B , 10E ); parameres simple of the " Bidessini " type, 2-segmented.

Variation.

Measurements (N = 20). Total length: 1.8-2.1 mm (mean 2.02); length without head 1.7-1.9 mm (mean 1.77); maximum width 0.9-1.0 mm (mean 0.91).

Occipital line. Faint and ill-defined to almost absent (only a few serial punctures visible instead).

Color. Usually darkly colored but a few specimens with paler, band-like markings on elytra.

Female variation: see below.

Metathoracic wings. Short, 2/3 or elytral length; venation visible in five dissected specimens from COL_MB_2018_10.

Female. External morphology as in male, with the dorsal surface shiny except for microreticulation on the head; dorsal sculpturation varies, either with microreticulation on the posterior ~1/3 of elytron so the surface appears slightly less shiny, or with microreticulation stronger over the entire dorsal surface so the surface appears dull (mesh-like, as in Fig. 11A ).

Etymology.

Named after the type locality, Páramo de Matarredonda. The word “matarredonda” is a noun in the nominative singular standing in apposition.

Identification notes.

The median lobe of the aedeagus is slightly more parallel-sided in ventral view than in the other subspecies (Fig. 10 E ). This subspecies is only reliably identified on the basis of the collecting locality and Cox1 data. In the COLLI sequence database this subspecies has one diagnostic character different from the other subspecies (Table 1 ).

Distribution.

Only known from the Páramo de Matarredonda but see below (Fig. 1 ).

Habitat.

Exposed, shallow, densely vegetated, stagnant bodies of water.

Note.

Specimens from a locality at 3,300 m en route to the Páramo de Matarredonda from Bogota city are morphologically intermediate between L. bogotensis matarredonda and L. b. bogotensis (Fig. 6B ), and they most likely belong to a hybrid population. Their haplotype is that of L. b. bogotensis (Fig. 2 ).

Figures

Figure 1. Map of sampling localities A overview of northwestern South America showing are of sampling depicted in " B " B colored areas represent districts in Paramo: Santanderes (blue), Boyaca (green), and Cundinamarca (brown).

Figure 2. Haplotype network for the Liodessus bogotensis complex using the partial gene COI- 5.

Figure 6. Variation in size and dorsal coloration of subspecies and a hybrid of Liodessus bogotensis A Liodessus b. matarredonda B hybrid specimens of L. b. bogotensis and L. b. matarredonda. Scale bar: 2 mm.

Figure 9. Median lobes in lateral view of Liodessus subspecies A L. bogotensis lacunaviridis B L. b. matarredonda C L. b. sumapaz. Scale bar: 0.2 mm.

Figure 10. Tips of median lobes in ventral view of Liodessus subspecies A L. bogotensis bogotensis B L. bogotensis almorzadero C L. bogotensis chingaza D L. b. lacunaviridis E L. b. matarredonda F L. b. sumapaz. Scale bar: 0.1 mm.

Figure 11. Liodessus bogotensis chingaza females showing detail of surface reticulation A head and pronotum of dull specimen B elytral tip of shinier specimen. Not to scale.