Calliscelio rungu Talamas & Copeland sp. nov.

(figs 26–36)

Description. Female (figs 26–32) body length: 2.3–2.4 mm (n=4).

Head (figs 26–29; 31). Color of head: black. Color of mandible: yellow to light brown with teeth darker. Color of interantennal prominence: black. Shape of head: subglobose. Occipital carina: present, complete medially. Occipital carina sculpture: crenulate. Hyperoccipital carina: absent. Sculpture of posterior vertex: granulate. Upper frons: convex, with transverse frontal ledge approximately midway between lateral ocellus and interantennal process. Setation of upper frons: absent. Scrobe shape: flat, antennal scrobe defined by smooth sculpture. Submedian carina: absent. Orbital carina: absent. Compound eye size: of normal proportions, not reduced. Compound eye setation: sparsely setose. IOS/EH: IOS greater than EH. Length of OOL: about 1 ocellar diameter. Inner orbits: parallel in frontal view. Central keel of frons: absent. Interantennal process: short, excavate along midline. Sculpture of frons between median ocellus and frontal ledge: granulate. Lower frons sculpture: granulate. Lower frons setation: dense, silvery, extending laterally onto gena. Clypeus shape: narrow, slightly convex medially. Mandible shape: sickle-like. Mandibular teeth: apex with 2, acute, subequal teeth (fig. 30). Arrangement of mandibular teeth: transverse. Gena: broad, convex, distinctly produced behind compound eye. Sculpture of postgena behind outer orbit: smooth to granulate-coriaceous. Antenna. Claval formula: 1-2-2-2-1. Color of A1–A12 (fig. 31): dark brown to black. Color of radicle: yellow to dark brown. Length of A4: shorter than A3. Length of A5: shorter than A4. Shape of A6: roughly spherical (fig. 31).

Mesosoma (figs 26–28). Color of mesosoma: black. Sculpture of dorsal pronotal area: punctate. Sculpture of lateral pronotal area: smooth anteriorly, coriaceous posteriorly. Notauli: present. Development of notauli: nearly percurrent. Parapsidal lines: present. Admedial lines: present. Netrion shape: moderately wide, open ventrally. Sculpture of netrion: punctate along anterior margin, otherwise smooth. Sculpture of mesoscutum: internotaular area densely punctate; lateral lobes mostly smooth with coriaceous microsculpture at humeral edges and at posterior end of notauli. Shape of mesoscutellum: semiellipsoidal. Foveolae of scutoscutellar sulcus between notauli: absent. Sculpture of mesoscutellum: smooth. Shape of metascutellum: rectangular with almost straight posterior margin, about 5.5× wider than long. Sculpture of metascutellum: rugulose punctate. Metanotal trough: smooth ventrally, dorsally with a line of fine punctures. Sculpture of prespiracular area: smooth. Sculpture of plical area: rugulose. Metasomal depression: wide, anteriorly extending to metascutellum in female. Mesopleural carina: present. Sculpture of mesepisternum below mesopleural depression: smooth with shallow punctation below posterior half of mesopleural carina. Sculpture of dorsal metapleural area: smooth. Sculpture of ventral metapleural area: smooth directly below metapleural sulcus, punctate rugulose ventrally. Legs. Color of coxae: dark brown to black. Color of femora: brown to dark brown. Color of tibiae: brown. Color of tarsi: light brown. Sculpture of hind coxa: smooth. Wings (fig. 32). Color of fore wing: mostly between basal vein and apex of postmarginal vein. Color of wing setation: brown. Basal vein: nebulous. Setae on submarginal vein in fore wing: short, erect, surpassing margin of wing. Length of marginal vein: distinctly shorter than stigmal vein. Length of postmarginal vein: slightly longer than stigmal vein.

Metasoma (figs 26–27). Color of metasoma: black. Shape of metasoma: lanceolate. T1: produced medially into elliptical horn (figs 26–28). Sculpture of T1 horn dorsally: transversely striate at apex; longitudinally striate posteriorly (fig. 28). Development of longitudinal striae on T2: not reaching middle of T2 (fig. 28). Sculpture of T3–T5: smooth (fig. 26). Shape of T6: elongate, more than twice as long as wide.

Male (figs 34–36). Body length: 2 mm (n=1). Similar to female, mainly differing by having the antennae filiform and the absence of horn on T1. Color of A1–A2: pale to dark brown (fig. 36). Color of A3–A12: dark brown to black (fig. 36).

Material examined. Holotype ♀, (ICIPE 32845), KENYA, Eastern Prov. Kasaala area 2.07846° S, 38.22530° E, 740 m, 6 m Malaise trap, just inside isolated woodland patch, 28.xi.–4.xii.2013, leg. Bukhebi J. & Copeland R. (NMKE).

Paratypes: 1♀, (ICIPE 32848): KENYA, Eastern Prov. Kasaala area, 2.07846°S, 38.22530°E, 740 m, MT, just inside isolated woodland patch, 28.xi.–4.xii.2013, leg. Bukhebi J. & Copeland R. (NMKE); 2♀, (ICIPE 1711, 30816): KENYA, Eastern Prov. Kasaala area, 733 m, 2.07836°S, 38.22517°E, MT, just inside isolated woodland patch 9–23.xii.2016, leg. Copeland R. (NMKE); 2♀, (ICIPE 30819–30820): KENYA, Eastern Prov. Mulu Musingila farm 689 m, 2.11412°S, 38.23989°E, MT, farmland near small, seasonally wet area, 27.xii.2016 – 10.i.2017, leg. Copeland R. (ICIPE); 6♀, (ICIPE 30821–30826): KENYA, Eastern Prov. Mulu Musingila farm, 689 m, 2.11412°S, 38.23989°E, MT, farmland near small, seasonally wet area, 13–27.xii.2016, leg. Copeland R. (ICIPE 30822, 30826: FSCA; ICIPE 30821, 30823–30825: ICIPE); 1♀, (ICIPE 30818): KENYA, Eastern Prov. Kasaala area, 733 m, 2.07836°S, 38.22517°E, MT, just inside isolated woodland patch, 27.xi.–11.xii.2014, leg. Copeland R. (NMKE); 1♀, (ICIPE 30817): KENYA, Eastern Prov. Kasaala area, 733 m, 2.07836°S, 38.22517°E, MT, just inside isolated woodland patch, 25.xii.2014 – 8.i.2015, leg. Bukhebi J. & Copeland R. (NMKE); 1♀, (ICIPE 75111): KENYA, Eastern Prov. Mulu Musingila farm, 689 m, 2.11412°S, 38.23989°E, MT, farmland near small, seasonally wet area, 11–25.xii.2017, leg. Copeland R.; 1♂, (ICIPE 32891): KENYA, Eastern Prov. Kasaala area, 733 m, 2.07836°S, 38.22517°E, MT, just inside isolated woodland patch 25.xii.2014 – 8.i.2015, leg. Copeland R. (NMKE).

Distribution. Kenya (fig. 33).

Etymology. The word “rungu ” is Swahili for a wooden club, often made of dark wood and with a point on the spherical head. Similarly, C. rungu has a pointed apex of the head and is dark in color. The epithet is treated as a noun in apposition.

Diagnosis. Calliscelio rungu is a remarkable species; the setal pattern of the dorsal head and mesosoma, with the setal color transitioning from copper to gold to silver, makes it easy to recognize. Among species of Calliscelio, the frontal ledge is unique to C. rungu and this alone will diagnose it. These conspicuous characters would likely be emphasized in the descriptions of other African Calliscelio (Nixon 1931, 1933; Risbec 1953, 1958), and we consider their absence from those treatments to be reasonable evidence that C. rungu is a new species. Furthermore, C. rungu does not fit any of the earlier descriptions. The descriptions by Nixon and Risbec included the number of mandibular teeth (bidentate only in C. erana and C. aphrodite), an important detail that simplified our comparisons. We were further able to eliminate C. benoiti (Risbec) and C. paulisiensis (Risbec) by the metascutellum, illustrated in the original descriptions as posteriorly rounded and triangular, respectively. Both forms are distinct from the transverse metascutellum of C. rungu. The size and shape of the metascutellum were discussed by Masner (1976) who considered C. benoiti as “an aberrant species with metanotal lamina reminiscent of Anteromorpha Dodd ”, leading us to consider that it may belong in a different genus.

Comments. Calliscelio rungu is known from two localities, Kasaala and the Mulu Musingila farm, 4.26 km apart from each other in xeric eastern Kenya. All specimens were collected in Malaise traps between November and January during the short rainy season. Most of eastern Kenya that is 40 km or more from the Indian Ocean coast is savannah, semi-desert or desert, beyond the ameliorating effect of the ocean on rainfall. In contrast with most of Kenya, rainfall is normally heavier in the eastern Kenya savannah during the short rainy season (November– January) than during the long rainy season (March–June). Kasaala is an area with a mosaic of small farms and secondary growth woodland. The Musingila farm is in a similar area except that woodland to farmland conversion is greater than at Kasaala. There is also a very small seasonal stream at the east end of the farm. Compared with coastal and upland Kenya, the eastern lowlands (ca. 400–1000 m in elevation) have been poorly sampled, particularly for microhymenoptera. Recent collecting in areas within these biomes has yielded many undescribed species including several from the Kasaala and Musingila farm locations. Future sampling will likely reveal the presence of many more unknown and rare insects.