RHINOLOPHUS RHODESIAE ROBERTS, 1946

ROBERTS’ S HORSESHOE BAT

Synonyms: None.

Holotype: TMSA 1325, adult female, collected by A. Roberts on 16 August 1913.

Type locality: ‘Southern Rhodesia’ (= Zimbabwe), Bezwe River, tributary of ‘Wanetsi’ (= Nuanetsi) River, −21.500° S, 31.167° E.

Referred specimens having molecular identifications: FMNH 228942 (SMG 19017), female, 228943 (SMG 19018), male, 228944 (SMG 19019), female, 228945 (SMG 19020), male, 228946 (SMG 19021), female, 228948 (SMG 19023), male, 228949 (SMG 19024), female, 228950 (SMG 19025), female, 228951 (SMG 19026), female, 228952 (SMG 19027), male, 228953 (SMG 19028), male, 228955 (SMG 19030), male, 228957 (SMG 19032), female, 228958 (SMG 19033), female, 228959 (SMG 19034), female, 228960 (SMG 19035), female, 228961 (SMG 19036), male, 228962 (SMG 19037), male, 228964 (SMG 19039), female, all collected on 2 May 2015 by S. M. Goodman, M. C. Schoeman and G. le Minter from Mozambique, Inhambane Province, Malashane Cave, 39.1 km Efrom Inhassoro, −21,668° S, 34,847° E, and situated <2 km from Chihalatan Cave referred to above.

Referred specimens having only morphological identifications: DM 7080, adult male, KwaZulu-Natal Province, Hlabeni Forest Reserve, −29.933° S, 29.766° E collected by D. Forbes on 29 July 2000; DM 12007 (adult male); DM 14034 (adult male), collected by M. C. Schoeman from KwaZulu-Natal Province, Pietermaritzburg, Ferncliff Nature Reserve, Ferncliff Cave, −29.550° S, 30.320° E ; DM 11270 (female), 11271 (male), 11272 (female), 11273 (female), 11275 (male), all collected by S. Stoffberg from Chihalatan Cave, 38.2 km Eof Inhassoro, Inhambane Province, Mozambique −21.671° S, 34.864° E ;. DM 11275 collected on 8 August 2006 while the other specimens were collected on 3 September 2007; FMNH 228956 (SMG 19031), collected 2 May 2015 by S. M. Goodman, M. C. Schoeman and G. le Minter from Mozambique, Inhambane Province, Malashane Cave, 39.1 km E from Inhassoro, −21,668° S, 34,847° E ; DM 13450 (female), DM13451 (female), collected on 8 May 2012 by J. Bayliss at Mozambique, Niassa Province, Mount Mecula, −12.068° S, 37.662° E.

Etymology: The name refers to the location in Southern Rhodesia (now Zimbabwe) where the type specimen was collected.

Re-diagnosis and description: Roberts (1946) described this subspecies as being slightly smaller than the nominate R. s. swinnyi based on slightly smaller body size, slightly longer tail, smaller ears and its bright ochraceous colour. Since the last-mentioned character is known to be an environmentally induced effect in many cave-dwelling bat species, it does not serve as a diagnostic character. In our analysis, molecular evidence closely matched our series from Chihalatan and Malashane Caves with Genbank sequences from the extreme northern South Africa (Pafuri), Zimbabwe (Dambanzara) and Zambia (Kalenda and Shimalala Caves). Since these localities encompass the type locality of rhodesiae (Bezwe River in Zimbabwe), and Pafuri is only 100 km south of Bezwe, we are confident to use this available name for this widespread taxon. The species can be further diagnosed by having echolocation peak frequencies around 100 kHz (99–102 kHz, N = 8 from Malashane Cave; Table 2), which are quite distinct from typical swinnyi (105–107kHz, N = 6; Table 2) as well as the new Gorongosa National Park taxon R. gorongosae sp. nov. (104–108 kHz, N = 16; Table 2). Noseleaf structure is distinctive, being characterised by a hastate lancet, not as concave as true swinnyi, less erect, low, rounded connecting process and more pronounced posterior lobe. Bacular structure of rhodesiae is clearly distinct from other swinnyi -like animals (see Figs 7, 8), being characterized by a distinctly longer tapered baculum with a distinctly broader base and shallow notchalong the lower portion of the shaft that isvisible in the lateral profile. Traditional morphometrics (Table 2; Fig. 4) do not differentiate rhodesiae from swinnyi proper; however, rhodesiae is clearly distinguished with minimal overlap from the distinctly smaller gorongosae sp. nov. Although quite small, the R. rhodesiae holotype falls within the range of variation of specimens assigned to R. rhodesiae from Mozambique, Zimbabwe, Zambia, northern South Africa (Pafuri, Limpopo Province), and Zanzibar (Table 2; Fig. 4). It falls clearly outside (larger than) the range of variation of the smaller gorongosae sp. nov. taxon (Fig. 4). Geometric morphometric results result in a better separation between rhodesiae and swinnyi s.s. with only minimal overlap (Fig. 5). Once again, the rhodesiae holotype from Bezwe River clusters within the range of variation of the rhodesiae taxon and outside the gorongosae sp. nov. or swinnyi taxa, thus validating the use of this name for this taxon.

Distribution and biology: Combined molecular and morphometric data suggest the widespread distribution of this taxon from central and northern South Africa through Zimbabwe, Zambia and Mozambique extending to Zanzibar (Fig. 11). Based on specimen assignments on morphological grounds, the species co-occurs with R. swinnyi in central KwaZulu-Natal at Ferncliff Cave, as well as occurring in close proximity in northern KwaZulu-Natal, recorded at Hlabisi Forest close to Ngome Forest where swinnyi was recorded (Fig. 11). The widespread extent of this taxon and its occurrence in northern South Africa is confirmed by the widespread occurrence of a hitherto unidentified 100 kHz acoustic type recorded in the Soutpansberg (Taylor et al., 2013), and Pafuri Region of northern Kruger National Park (Taylor & Parker, unpublished data).