Amietia angolensis (Bocage, 1866)

Conradie, Werner, Keates, Chad, Verburgt, Luke, Baptista, Ninda L. & Harvey, James, 2023, Contributions to the herpetofauna of the Angolan Okavango- Cuando-Zambezi river drainages. Part 3: Amphibians, Amphibian & Reptile Conservation (e 325) 17 (1), pp. 19-56 : 48

Amietia angolensis (Bocage, 1866)

Angola River Frog ( Fig. 36 ; Map 35 )

Material (16 specimens): PEM A12627 , roadside ditch 10 km SW of Cuito town , -12.44815° 16.88118 °,

1,742 m asl; PEM A12645, confluence of Cuito and Calua rivers, -12.74878° 18.35433°, 1,413 m asl; PEM A12653–7, INBAC: WC-5245, Kuvango Hydro Plant Site, -14.38775° 16.29365°, 1,441 m asl; PEM A12669, Campsite 1 below rapids, west of Fundo village, -13.04359° 16.37439°, 1,571 m asl; PEM A12671–3, INBAC: WC-5228, Camp 3, Malova Village, Mipanha River, -14.09140° 16.41476°, 1,553 m asl; PEM A12834, 31 km W of Menongue, Cueli River, -14.70511° 17.38014°, 1,392 m asl; PEM A13785, Aquaculture farm outside Cuito, -12.43972° 16.89833°, 1,689 m asl; PEM A13786, Dam/Hydroplant on Rio Cuquema, -12.42556° 16.81856°, 1,640 m asl; PEM A14678, Villa Menongue, -14.63015° 17.63465°, 1373 m asl; bridge between Huambo and Cuito, -12.47056° 16.82389°, 1,643 m asl. Additional material (2 specimens): SAIAB 204011 (2 specimens), Cuchi River below bridge, -14.70272° 17.37864°, 1,393 m asl. Description: Large species; large tympanum, with an elevated ridge running from just behind the eye to arm; elevated paravertebral ridges continuous from behind eyes to groin, while the other ridges are broken (except in PEM A12834, where the dorsum is smooth); two and a half phalanges of longest toe free of webbing; small but conspicuous inner metatarsal tubercle; no outer metatarsal tubercle; well-developed subarticular tubercles; protruding eyes that are contained in outline of jaw viewed from below. Dorsum brown to dark green with scattered darker blotches; gular region dark with irregular white blotches that sometimes fuse to form lines; light vertebral stripe often present; dorsal tibia with dark crossbands; ventrum immaculate, except in two specimens ( PEM A12654 and A12657) where the throat mottling extends onto the groin. In breeding males, the dorsum is yellowish, spiny with black-tipped asperites, and the nuptial pads on the thumbs are swollen. Adult males (n = 13) varied from 51.1–71.9 (63.9) mm (largest male: PEM A12671). Habitat and natural history notes: All material was found associated with the western tributaries of the Cubango River, where the substrate is rocky and the water is fast flowing. A single subadult specimen was found at the confluence of the Calua and Cuito rivers. This species is absent from the rivers and floodplains of the main Okavango River basin, possibly due to the sandier substrate. Comments: Recent phylogenetic revisions of the genus led to the identification and description of numerous cryptic species ( Channing and Baptista 2013; Larson et al. 2016; Channing et al. 2016). In the process, A. angolensis , which was once considered to have a wide distribution across most of southern African, was restricted to Angola and is now regarded as a country endemic ( Channing and Baptista 2013; Channing et al. 2016).

Figures

Map 35. Distribution of Amietia angolensis in Angola.

Fig. 36. Adult male Amietiaangolensis from west of Menongue. Photo by Werner Conradie.