Ropalidia nubila Polasek 2025, sp. nov.
Creators: name: Polašek, Ozren
name: Onah, Ikechukwu
name: Kehinde, Tope
name: Rojo, Veronica
name: Noort, Simon Van
name: Carpenter, James M.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Vespidae
Ropalidia
Ropalidia nubila

description: Ropalidia nubila Polašek sp. nov.
urn:lsid:zoobank.org:act: C485670B-D37A-498A-AA72-B9FEE8ACD24A
Type specimens: Holotype: Upington, South Africa, 1♀ (AMNH _ IZC00179591). Paratypes: 18 ♀♀ with same collection data as holotype; Keimoes, South Africa, 3♀♀ (AMNH); Fish river canyon, Namibia, 1♀ (MFNB); paratype / allotypes [4♂♂]: 2♂♂ with same collection data as holotype; Keimoes, South Africa, 1♂ (AMNH _ IZC00179614); Kimberly Ritchie, South Africa, 1♂ (OLM). The total number of examined specimens: 23♀♀, 4♂♂.
Diagnosis. An interesting member of the capensis -group, with light brown basal body colour, distinct whitish-yellow markings and a developed fore wing apical spot. Females are morphologically very similar to R. antennata (DE SAUSSURE), while males have specific clypeus and antenna morphology, sufficient for the species determination.
Description. Females. Wing length: 6.3–7.1 mm. Colour. One of the least variable African Ropalidia, with minimal morphological and colour differences across all examined specimens. Basal colour light brown, with yellowish-white markings (Figure 15b). Clypeus yellow with large light brown spot attached basally, yielding equally broad yellow encircling line (Figure 15a). Inner orbit with thicker yellow line, interantennal area without any yellow. Gena brown with small yellow spot; mandible yellow with lightly brown centre. Frons, vertex and tempora lightly brown, area around ocelli black. Whitish-yellow areas of mesosoma include line underneath pronotal carina, postero-dorsal angle on pronotum, postero-medial quadrant of tegulae, postero-lateral angle of scutellum (sometimes suffused and nearly gone), bilateral spot on metanotum and all three coxa pairs (coxa I entirely yellow, coxa II and III with a lateral yellow line; Figure 15b). Darker brown streaks on mesonotum (Figure 100a). Streaks of suffused black colour may be seen on the posterior half of mesopleuron, metapleuron and sometimes very slightly on propodeum. T1 with bilateral yellow spot, T2/S2 with a wide posterior yellow band, T3–T5 and S3–S4 with suffused posterior yellow band (Figure 15b). Legs uniformly brown, tarsi darker. Wings transparent, nervature light brown, stigma brown. Apical spot developed, lightly brown (Figure 15b). Antenna ferruginous or slightly tinted darker from above (darker than the basal body colour), orange underneath (Figure 15b).
Head. Clypeus resembling that of R. antennata (DE SAUSSURE), with straight upes and developed OCA; its surface finely punctate, covered by short golden-whitish setae (Figure 15a). Mandible barely widened basally. Inner orbit impunctate, frons densely and finely punctate. Gena 0.7 times as wide as eye, tempora thinner, about half of gena width. Occipital carina developed, reaches mandible. Ocellar triangle wider basally. Scape longer than AF1, AF2 about 1.2–1.4 times as wide as long (Figure 15a).
Mesosoma. Mesosoma shallowly punctate, punctures on pronotum larger. Entire mesosoma covered by short yellowish pubescence, with whitish traces on propleura, mesopleuron and dorsal pronotal margin. Mesonotum shallowly punctate, obscured by short pubescence. Parapsidal furrows strongly developed (Figure 100a). Scutellum with sparse punctures and moderately developed central furrow, metanotum with larger posterior impunctate area. Inferior propodeal carina weak, striae weak. Propodeal excavation with dense golden setae, commonly directed downwards, but some specimens may even have horizontal setae direction.
Metasoma. T1 pyriform, evenly curved (in lateral view), with sparse and shallow punctures distally (Figure 15b); T1 covered by yellow-golden pubescence, S1 covered by silvery pubescence of equal length. T2 with longer section with parallel sides, covered by shallow directional punctures (Figure 15b). T2 lamella whitish-yellow, transparent; T2/S2 notch wide and obtuse, T2/S2 suture developed.
Males. Wing length: 6.2–6.9 mm. Colour. Mainly resembles females, but with more yellow on head and more back on mesosoma underside. Clypeus, mandibles, inner orbit and interantennal area merged in yellow; gena with yellow spot (Figure 56a). Head with more black than females; black markings can be as reduced to small area surrounding ocelli, extending to very melanic specimens that have streaks of black areas from ocelli to antennal socket. Line underneath pronotal carina, anterior surface of mesopleuron, bilateral spot on metanotum, anterior surface of all coxa pairs (dorsal surface brown, or sometimes even yellow in coxa I), femur I and II (sometimes and III) with a proximal suffused yellow line, tibia brown, tarsi somewhat darker than the tibia and femur (Figure 100b). T1 with bilateral yellow spot, T2/S2 with a continuous posterior yellow band, T3–T5, S3–S4 with suffused yellow bands.
Head. Clypeus wider than long, with mildly projecting and rounded apex, upes short (Figure 56a). Clypeal surface very finely punctate, hardly discenrible underneath layer of short and dense silvery pubescence that extends on mandible, gena and inner orbits. Antenna very clavate, comparable to R. capensis (DE SAUSSURE); scape twice wider than AF1 base, conspicuously longer than AF1, AF2 broader than long. Tyloids very developed, originating on AF2 (Figure 56b). Terminal flagellomere elongated and curved, similar to R. capensis (DE SAUSSURE).
Mesosoma. Tarsal spur I very well developed.
Metasoma. S7 with small central concave area.
Male-female pairing strength. High, males are part of type series.
Distribution. South Africa (Northern Cape), southern Namibia.
Etymology. The name is the Latin adjective nubilus -a -um (“cloudy”), and refers to the faint but developed apical spot of the fore wing.
Similar species. Females may resemble lightly coloured R. antennata (DE SAUSSURE). Males are easily separated from other species by morphology of clypeus and dense pubescence that obscures punctures.
Genetics.A single genotyped specimen yielded a somewhat confusing phylogenetic position (see the R. capensis DE SAUSSURE section for additional discussion). However, the quality and distinctiveness of the submitted sequence were sufficient for a BIN identification (BOLD:ADR2390).
description: Published as part of Polašek, Ozren, Onah, Ikechukwu, Kehinde, Tope, Rojo, Veronica, Noort, Simon Van & Carpenter, James M., 2025, Revision of the mainland African species of the Old World social wasp genus Ropalidia Guérin-Méneville 1831 (Hymenoptera; Vespidae), pp. 1-142 in Zootaxa 5626 (1) on pages 110-111, DOI: 10.11646/zootaxa.5626.1.1, http://zenodo.org/record/15325272