Ropalidia nigrofemorata ( CAMERON 1910 )

Ropalidia nigrofemorata ( CAMERON 1910) View in CoL

Icaria nigrofemorata CAMERON 1910

Type material. One female, labelled “ Usambara ”, “ Sjöstedt ”, “ Icaria nigrofemorata Cam. Type ”, the red label “ 44 ” with another handwritten number “ 75 ”, labelled as NHRS-HEVA 000007510 (photograph examined). The specimen has a detached metasoma, which was considered lost and the type unusable ( Schulthess Rechberg, 1913). The metasoma has been recovered in the meantime, and it is available in a separate tube next to the specimen. The specimen does not fit the species description adequately. The description suggests no yellow colour on the clypeus (the holotype has a yellow clypeal apex); mandibles are supposedly fuscous-black (the holotype has yellow markings on the mandibular base), coxa, trochanter and femora are described as black (they are brown). These inconsistencies in the colour pattern could be a consequence of the poor illumination of the microscope at that time. Bequaert considered it as a doubtful species, but did not provide any synonymy or additional taxonomic note ( Bequaret, 1918).

Comments. Comparatively smaller species, with weak or absent scutellar median carina. It forms a cluster of darkly coloured and smaller species, with R. tenebrica sp. nov. and R. tenuipilosa sp. nov. The defining criteria for this species include dense golden pubescence of the mesonotum and T2, and darker femur compared to the tibia. Males were previously unknown and are described here for the first time.

Males.

Material. Arabuko-Sokoke forest , Kenya, 1♂ ( ICIPE.07) ; Tiwi beaches, Kenya, 2♂♂ ( SNM.038, SNM.075) ; Busia, Uganda, 1♂ ( NHM.710) . The total number of examined specimens: 4♂♂ .

Description. Wing length: 8.0– 8.6 mm. Colour. Colour pattern resembles females, with more yellow on head and mesosoma ( Figure 76 View FIGURE 76 bb). Clypeus, inner orbit, interantennal area and mandible yellow, except postero-basal dark brown triangle on mandible ( Figure 76 View FIGURE 76 bb); gena with smaller, elongated yellow area. Frons, vertex and tempora brown. Mesosoma dorsally brown, underneath with numerous yellow markings; anterior surface of mesopleuron, coxa I and II, femur I and II ventrally completely yellow (in one specimen even coxa and femur III have yellow markings). General leg colour pattern similar to females; femur dark brown, tibia light brown, tarsi similar to femur. Wings translucent, apical spot dark or black, stigma yellowish and transparent ( Figure 41 View FIGURE 41 aa). Metasoma with predominantly basal colour; T2 with thin posterior ochre or reddish line ( Figure 74 View FIGURE 74 dd). Scape dark brown dorsally, pedicel and AF1 ferruginous-brown (including distal part of AF1), AF2–11 black from above, AF11 with faintly brownish tip ( Figure 74 View FIGURE 74 bb); entire underside of antenna yellow.

Head. Clypeus with evenly and strongly curved upes, similarly curved juxtamandibular excavation and moderately projecting, slightly depressed, obtuse apex ( Figure 76 View FIGURE 76 bb). Basal third or a half largely punctate; entire surface covered by silvery-whitish pubescence. Similar pubescence extends onwards to frons, with yellowish longer protruding setae. Gena shallowly punctate, covered by short whitish pubescence. Ocelli acute forwards. Scape about as long as AF1, AF2 1.3–1.5 times as long as wide. Tyloids very shiny ( Figure 77a View FIGURE 77 ), originate on AF4. Terminal flagellomere elongated, curved, tip obtuse or subacute ( Figure 74 View FIGURE 74 bb).

Mesosoma. Pronotal carina laterally and dorsally almost equally wide ( Figure 74 View FIGURE 74 aa). Tarsal I spur not developed.

Metasoma. Terminal sternum concave.

Male-female pairing strength: high, confirmed by the mt DNA.

Distribution. Kenya, Tanzania, Uganda.

Genetics. There are five different clusters when three related species are considered (Supplementary Figure 26 View FIGURE 26 ). The first and the most distant cluster belongs to R. nigrofemorata (CAMERON) , with a BIN assignment BOLD: ADM2242. There were two sequenced specimens in this cluster, both collected in Kenya (notably, these two specimens have a separate 28s rDNA sequence). The second cluster of R. nigrofemorata (CAMERON) is present in the Western parts of Tanzania (Kiberashi region). It is characterized by a high degree of similarity with the first cluster, but with a less dense golden pubescence layer on mesonotum and T2, which can even be silvery in a few examined specimens. This cluster was given a separate BIN assignment, BOLD:ADR2755. The third cluster belongs to R. tenuipilosa sp. nov., with BIN BOLD:AEA4654. The fourth one is attributable to R. tenebrica sp. nov., designated as BOLD:ADR2309. Finally, the fifth cluster, BOLD:ADN5333, comprises four genotyped specimens, among which there are three specimens of R. tenuipilosa sp. nov. and one of R. tenebrica sp. nov. This cluster has multiple problems since the four specimens originated from the same location. Possibly the most parsimonious solution is that this is phenotypically deviant R. tenuipilosa sp. nov. However, this solution contradicts the specimen, which has silvery pubescence. In addition, there are several specimens of R. tenebrica sp. nov. from Namibia with different colour (more brown on the body, light-grey apical spot of the fore wing), suggesting that this entire cluster likely contains more currently undescribed taxa.