Metrodora rana, Bolivar, 1887

Metrodora rana View in CoL Bolívar, 1887

( Figs. 1–6 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 , Map 1)

Metrodora rana View in CoL Bolívar, 1887: 248. Holotype: male. PERU, Alto Amazonas. Depository : MNCN.

Redescription. Male. Small size (7.5–8.5 mm). Body compact, robust, and rugose ( Figs. 1A, C View FIGURE 1 ; 2A–B View FIGURE 2 ). Coloration predominantly brown with some ocher and gray spots or stripes ( Fig. 1 View FIGURE 1 ). Head brown, scape, pedicel, and flagellomeres light ochre or light brown; labrum and clypeus ochre with the distal margin brown delineated as a conspicuous stripe; palpi ocher with diffuse brown spots; frontal costa, medial, and lateral carinae of the vertex delineated in ochre ( Figs. 1D View FIGURE 1 ; 3A View FIGURE 3 ). Femora brown with the surface outlined in dark brown and ochre ( Figs. 1A View FIGURE 1 ; 2A View FIGURE 2 ; 3D–E View FIGURE 3 ); tibiae ocher with grayish-brown stripes; all tarsomere ochre, with only the last segment of each tarsomere brown at the apex ( Figs. 1A View FIGURE 1 ; 2A View FIGURE 2 ). Head little exserted, taller than wide; eyes subglobose, in letral view, with a rounded dorsal surface, almost straight ventral margin and, in frontal view, slightly elevated above the vertex, occupying a quarter of the cephalic capsule; vertex wider than an eye; medial and lateral carinae similar in length in frontal view ( Fig. 3A View FIGURE 3 ), medial carina little produced in lateral view, surpassing slightly the eyes ( Fig. 3B View FIGURE 3 ); frontal costa bifurcation located at the middle of the eyes; scutellum almost narrow, fascial carinae slightly divergent ( Fig. 3A View FIGURE 3 ); fascial carinae compresso-elevated between the antennae, above and below abruptly sinuate in lateral view ( Figs. 1A View FIGURE 1 ; 3B View FIGURE 3 ); upper margin of the antennal grooves almost at the same level of the lower margin of the eyes; lateral ocelli between the inferior part of the eyes, near the base from where each branch of the fascial carinae diverges; medial ocellus on the lower margin of the scutellum ( Figs. 1D View FIGURE 1 ; 3A View FIGURE 3 ); antennae with 14 segments; flagellomeres cylindrical (except for the conical last segment), usually elongated, longer than wide (except for the short second segment); palpi narrow, with apical segments moderately depressed ( Figs. 1D View FIGURE 1 ; 3A View FIGURE 3 ). Thorax. Anterior margin of the pronotum almost straight; prozonal carinae developed ( Figs. 1C View FIGURE 1 ; 2B View FIGURE 2 ; 3C View FIGURE 3 ); pronotal disc flattened above ( Fig. 2B View FIGURE 2 ); median carina subelevated, moderately undulated at the level of the fore and hind coxae in lateral view; pronotal apex not surpassing the tip of abdomen, pointed, and slightly upcurved in lateral view ( Figs. 1A View FIGURE 1 ; 2A View FIGURE 2 ); external lateral carinae finely denticulated and curved; infrascapular area wide and extending to the fifth or sixth abdominal segment; lateral area originating from the upper half of the infra-scapular area and with same width from the base to the apex in lateral view ( Figs. 1A View FIGURE 1 ; 2A View FIGURE 2 ); angles of the lateral lobes triangular-shaped, outwardly acute and flattened in dorsal view ( Figs. 1C; 1E View FIGURE 1 ; 2B View FIGURE 2 ; 3C View FIGURE 3 ). Wings absent. Legs slightly elongated. Fore and mid femora rectangular, basally constricted and then expanding, dorsal margin curved, ventral margin with three small undulations ( Figs. 3D–E View FIGURE 3 ); hind femora with ante-genicular tooth moderately developed; genicular tooth triangular and with apex rounded ( Figs. 1A View FIGURE 1 ; 2A View FIGURE 2 ). Hind tibia armed with four small spines on each dorsal margin; the first and third segments of the hind tarsi equal in length ( Fig. 2A View FIGURE 2 ). Abdomen unmodified ( Fig. 3F View FIGURE 3 ). The last two segments dorsally divided by a shallow groove that connects to epiproct. Epiproct lanceolate with a hexagonal plate on each side, the distal one subtriangular, tapering towards the apex ( Fig. 3G View FIGURE 3 ). Cerci conical, tapering towards the apex and moderately diverging to the sides ( Fig. 3H View FIGURE 3 ). Penultimate sternite long, 2.5 times longer than the subgenital plate, slightly curved upwards ( Fig. 3F View FIGURE 3 ), subgenital plate short, cupuliform in lateral view ( Fig. 3F View FIGURE 3 ), and apex divided by a shallow V-shaped notch in axial view ( Fig. 3H View FIGURE 3 ). Pallear plates smooth, lanceolated, and separated by a medial groove ( Figs. 3G–H View FIGURE 3 ).

Female (new). Similar to the male in shape, coloration, and size ( Figs. 4 View FIGURE 4 ; 5 View FIGURE 5 ). The main differences include more conspicuous undulations on the median carinae of the pronotum ( Fig. 4A View FIGURE 4 ). Also distinguished by the ambisexual characters: ninth and tenth tergite divided by a wide groove ( Figs. 5F–G View FIGURE 5 ) that extends and connects with the epiproct ( Fig. 5G View FIGURE 5 ); epiproct triangular, divided into three plates, two lateral hexagonal plates on each side and a distal subtriangular one with rounded apex ( Fig. 5G View FIGURE 5 ); cerci conical tapering towards the distal section ( Fig. 5F View FIGURE 5 ). Ovipositor valves with normal development and covered with bristles ( Fig. 5F View FIGURE 5 ); subgenital plate rectangular, longer than wide, with posterior margin rounded and with a small extension in the middle ( Fig. 5H View FIGURE 5 ).

Specimens examined. 1 male, 1 subadult male, and 1 female. COLOMBIA, Amazonas, PNN Amacayacu , - 3°50’02.0”S 69°54’00.0”W; 20. VI GoogleMaps .2024, 70 m. R. Quintana leg. (CAUD). 1 male and 1 female. BRAZIL, Amazonas, Tabatinga, Umariaçu , 4°15’43.2”S 69°54’59.4”W; 15. VI GoogleMaps .2024, 75 m. R. Quintana leg. (CAUD). 1 male, BRAZIL, Amazonas, Borba , Rio Abacaxis, P [a]xiúba, 04°28’48”S, 58°34’24”W, 02–04. VI GoogleMaps .2008, J.A. Rafael e equipe [and team], Arm. Malaise ( INPA) . 1 male, lectotype. PERU, Hautes, Amazones (= Upper Amazon ), [Loreto, Yurimaguas], Staudinger, Cat. Tipos N ° 140 ( MNCN) .

Distribution. Peru, Alto Amazonas (=Upper Amazon); Colombia, Amazonas department and Brazil, Amazonas states (new records) (Map 1).

MAP 1. Distributional map of Metrodora rana .

Measurements (in mm) male / female. CFP: 7.5–8.5 / 8.5–9.5. PL: 7.0–7.5 / 7.0–7.5. PLB: 2.0–2.2 / 2.5–2.5. FFL: 1.5–2.0 / 2.0–2.3. FTL: 1.5–1.8 / 1.8–2.0. MFL: 2.0–2.5 / 2.0–2.5. MTL: 1.8–2.2 / 2.2–2.5. HFL: 3.0–4.5 / 5.0–5.5. HFW: 1.5–1.8 / 2.0–2.5. HTL: 3.0–3.5 / 4.0–4.5.

Comparison. M. rana is compared to the other species of the genus, Metrodora colombiae Günther, 1939 . M. rana differs from M. colombiae in the number of antennal segments, M. colombiae has nine segments, in contrast to the 14 segments of M. rana . The fastigium, particularly the medial carina, protrudes between the middle of the eyes and the antennae in M. colombiae , whereas this does not occur in M. rana . Regarding the pronotum, in M. rana , the lateral lobes are noticeably expanded outward, and the apex is pointed in the dorsal view. In contrast, M. colombiae does not have expanded lateral lobes, and the ventral margin or apex of these lobes is rounded.

M. rana View in CoL also resembles the Platytettix Hancock, 1906 species, as they do not have a fastigium that conspicuously surpasses the eyes or the first antennal segments. However, they differ in the scutellum, which is almost narrow in M. rana View in CoL but wide in Platytettix species. M. rana View in CoL has a sub-elevated median carina and a flat pronotal disc, whereas species of Platytettix View in CoL have an elevated median carina that forms a hump, rising conspicuously and occupying the anterior half of the pronotal disc.

Comments on M. rana status. The males studied here do not differ significantly from the type male ( Figs. 1 View FIGURE 1 ; 2 View FIGURE 2 ). Only subtle chromatic variations are evident. For example, the type male has fewer brown spots on the legs ( Fig. 1A View FIGURE 1 ) compared to the additional specimens studied ( Fig. 2A View FIGURE 2 ). The terminalia may appear different, but the terminalia of the males studied may look more swollen than in the type male because the subgenital plate was slightly lowered to observe the pallear plates ( Fig. 3G View FIGURE 3 ). However, it is very similar to the type specimen in a normal position.

The coloration of all the specimens studied here does not differ notably, but this species may present color variation. For example, a female photographed in Maynas, Peru ( Fig. 6A View FIGURE 6 ; https://www.inaturalist.org/ observations/106343620), matches the coloration of the males and females studied here. However, a male recorded in Tabatinga, Brazil ( Fig. 6B View FIGURE 6 ; https://www.inaturalist.org/observations/76678880), differs in coloration, being dark brown with a yellowish-white stripe outlining the lower edge of the lateral lobes of the pronotum.

Fortunately, one of the males studied here from Borba had one antenna complete, and 14 segments could be counted. Additionally, in the photographs published on iNaturalist of this species, 14 segments can be observed, fulfilling the diagnosis of the subtribe Metrodorina ( Cadena-Castañeda et al., 2025) . This characteristic is confirmed, which is important for this species, as it is the type taxon of the subfamily Metrodorinae s.s., and the stability of this taxon depends significantly on its characters.

Taxonomic comments. Recently, additional species of Metrodora were described by Kasalo et al. (2025). The publication by Kasalo et al. (March 6, 2025) was released just two days after the contribution by Cadena-Castañeda et al. (March 4, 2025). These two studies were conducted independently by each group of authors, unfortunately resulting in two species being synonyms between the two publications.

We propose the synonymization of Metrodora ala Kasalo & Skejo, 2025 syn. nov. under Hebardidora kasaloi Cadena-Castañeda & Tavares, 2025 . Both species are distributed in the same region of southern Costa Rica, specifically in the humid Pacific forests of Puntarenas. They share diagnostic characteristics distinguishing them from other species included in Hebardidora Cadena-Castañeda & Tavares, 2025 : the medial carina protrudes upward between the eyes, forming a small conical prolongation; the lateral lobes of the pronotum are noticeably expanded laterally, triangular in shape, with the lower margin rounded anteriorly and pointed at the apex in dorsal view. Additional characters, such as the facial carinae and pronotum shape, particularly the elevation and undulation of the median carina, as well as the shape of the anterior and middle femora, do not show sufficient differences to justify their recognition as distinct species. The synonymization of Metrodora ala syn. nov. is likely due to Kasalo et al. (2025) being unaware of the monograph by Cadena-Castañeda et al. (2025), given the close publication dates.

Additionally, we synonymize Metrodora mollilobata Kasalo & Skejo, 2025 syn. nov. under Hebardidora harroweri (Hebard, 1924) . Both species share the same diagnostic characteristics without significant variation to warrant their separation: the broad shape of the scutellum in both sexes remains consistent across specimens, serving as a key trait that distinguishes H. harroweri from other Hebardidora species. Likewise, the lateral lobes of the pronotum, in dorsal view, lack a pointed apex, unlike other Central American Hebardidora species. The only notable variation between Metrodora mollilobata syn. nov. and H. harroweri is a slightly more pronounced hump in the former; however, its overall shape remains similar, suggesting intraspecific variation. Consequently, by formalizing this synonymy, the distribution range of H. harroweri extends from central Panama to northwestern Costa Rica.