Catharus mentalis Sclater and Salvin 1879

Halley, Maưhew R., Catanach, Therese A., Klicka, John & Weckstein, Jason D., 2023, Integrative taxonomy reveals hidden diversity in the Catharus fuscater (Passeriformes: Turdidae) complex in Central and South America, Zoological Journal of the Linnean Society 199 (1), pp. 228-262 : 257-258

Catharus mentalis Sclater and Salvin 1879

Cochabamba nightingale-thrush

( Figs. 15 , 16 )

Catharus mentalis Sclater and Salvin 1876: 352, 1879: 591 ; Seebohm 1881: 285; Sharpe 1902: 182; Warren and Harrison 1971: 346.

Catharus fuscater mentalis Berlepsch 1902 , Hellmayr 1934: 467; Bond and Meyer de Schauensee 1942, Bond 1956: 242; Ridgley and Tudor 1989: 109; Fjeldså and Krabbe 1990: 554; Clement 2000: 299; Collar 2005: 700 (in part); Halley 2020, Halley 2021.

Catharus fuscater Meyer de Schauensee 1966: 412 (in part); Meyer de Schauensee 1970: 342 (in part); Schulenberg et al. 2007(in part); Vidoz 2009, Remsen et al. 2023 (in part).

Type material

Monotypic species. NHMUK 1885.3 .2.35 (syntype), study skin, from the Salvin–Godman Collection, collected by C. Buckley at ‘Suape’ in ‘prov. Yungas, Bolivia’ (= Suapi, La Paz, approximately –15.30˚, –67.31˚; see: Paynter 1992: 141), in 1876 ( Warren and Harrison 1971: 346) ; NHMUK 1885.3 .2.36 (syntype), collected by C. Buckley in ‘Yungas’ (presumably at Suapi , La Paz) in 1876 ; NHMUK 1886.8 .2.20 (syntype), collected by C. Buckley at ‘Suapi’, Bolivia. These specimens were not examined in this study. Label data were provided by A.L. Bond (in litt.) .

Geographic range

Occurs in southern Peru, east of the Río Apurímac, east to Santa Cruz, Bolivia (Vidoz 2009).

Adult specimens examined

Bolivia (N = 12): La Paz (five males, three females): Laguna Zongo: DMNH 67204 , 67207 (males), DMNH 67201 , 67206 (females); unspecified locality on the Río Aceramarca : AMNH 229261 (male); Sandillani: AMNH 138743 (male); Nequejahuruira: AMNH 229258 (male), AMNH 229257 (female) ; Cochabamba (two males, one female): Cerro Incachaca : CM 120346 , FMNH 181675 (males), CM 120345 (female) .

Peru (N = 9): Cusco (five males, two females): La Esperanza, Paucartambo: FMNH 433742 , 433738 (males), FMNH 433740 (female); Pillahuatta, Puacartambo: FMNH 430057 (male); Bosque San Luis: FMNH 299706 (female); Limacpunco: FMNH 222381 (male) ; San Pedro Village: FMNH 364458 (male); Puno (one male): Oconeque: ANSP 102367 (male) .

Immature specimens examined

Bolivia (N = 6): La Paz (five males, two females): Laguna Zongo: DMNH 67200 , 67202 , 67203 , 67205 (males), DMNH 67198 , 67199 (females); Acara: AMNH 229260 (male) .

Peru (N = 3): Cusco (one male, two females): Occobauiba Valley, Tocopoquen : USNM 273314 (female); Bosque San Luis: FMNH 299705 (male); Pensión Suecia, km 138.5 on Cusco-Shintuya Highway, Cosnipata Valley : FMNH 398318 (female) .

Audio recordings examined

Bolivia (N = 3): La Paz: Fuertecillo: XC 123041; Río Milluni near Titi Amaya, Inquisivi: XC 1998; Muñamachay: XC 73252.

Peru (N = 4): Junín: Cordillera Vilcabamba, headwaters of Río Poyeni : ML 92162 ; Puno: Sina: ML 148105, 148129, 148130.

Diagnosis

Genetics: In the UCE tree, samples of C. mentalis formed a clade that was sister to a large South American clade composed of samples of C. o. opertaneus , C. o. tenebris ssp. nov., C. b. berlepschi , and C. b. nebulus ssp. nov.. In the ND2 tree, samples of C. mentalis also formed a clade, but its placement in the broader phylogeny of the complex was unresolved. The divergence of C. mentalis from C. f. fuscater was estimated at 2.4 Mya (95% HPD = 1.9–3.0), and C. mentalis was also highly divergent from C. b. nebulus ssp. nov., its northern geographic neighbour and the only population likely to establish secondary contact with it during glacial maxima (mean uncorrected p -distance = 0.07 ± <0.01). ABGD and ASAP analyses both identified C. mentalis as an independent genetic cluster.

Morphology: Specimens of C. mentalis exhibited polychromatic plumage colour, with two distinct colour phenotypes in males, unlike other taxa in the complex ( Fig. 8 ), except possibly C. f. fuscater and C. b. nebulus ssp. nov. (see above). Male specimens were clearly separable into ‘grey’ ( FMNH 222381, FMNH 430057) and ‘brown’ ( ANSP 102367, FMNH 181675, FMNH 299705, FMNH 364458) phenotypes. ‘Grey’ males were similar to C. f. sanctaemartae males, but with slightly browner (and less dark) breasts and throats and reduced black on the chin. ‘Brown’ males resembled C. mentalis females in plumage colour, and in having a black maxilla (a retained juvenile character).Females of C. mentalis were similar in colour to C. f. fuscater females ( Tables 3 , 4 ).

Voice: Catharus mentalis was distinguished from all taxa except C. o. tenebris ssp. nov., C. o. opertaneus , and C. b. nebulus ssp. nov., by its Type 3 (‘short/simple’) punctuation call structure. Its ‘ascending’ blurred call was of higher frequency, simpler in structure, and shorter in duration than the ‘check-shaped’ blurred calls of C. b. nebulus ssp. nov. and C. b. berlepschi ( Fig. 11 ). Among these taxa, the punctuation calls of C. mentalis were the simplest in structure ( Fig. 9 ). No tetradic song contours were detected in C. mentalis ( Fig. 12 ). Our classification system for song contours was unable to score a remarkably slow-paced song ( BAC) followed by a rapid trill ( XC 123041) and a six-note contour that featured a typical BA contour followed by an extremely rapid CDAB contour ( XC 1998). Although our sample of recordings is small, these two songs were unique in our dataset, suggesting that C. mentalis is vocally divergent from the rest of the complex. Of the three triadic contours ( ACB, BAC, CBA) detected in C. mentalis , two ( ACB, BAC) were detected in its northern neighbour (C. b. nebulus ssp. nov.).

Comments

To our knowledge, the plumage polychromatism of C. mentalis is novel in the C. fuscater complex (except possibly in C. f. [ fuscater ] and C. b. nebulus ssp. nov., see above) and unprecedented in the genus Catharus . This pattern is illustrated by two specimens with enlarged testes ( FMNH 433738, 433742), collected at the same site in November 2001, a ‘mossy forest’ at La Esperanza (2800 m. elevation), north-east of Paucartambo, Cusco, Peru ( Fig. 8 ).

Figures

Figure 8. Side view of polychromatic adult plumages in C. [f.] mentalis (from left to right): 1, FMNH 433742, a ‘grey’ male with enlarged testes; 2, FMNH 433738, a ‘brown’ male with enlarged testes; 3, FMNH 364458, a ‘brown’ male with testes not enlarged; 4, FMNH 433740, an adult female with an enlarged ovary.Adults of both colour types (FMNH 433742, 433738) were collected at the same site in November 2001. Photograph by M.R.H.

Figure 9. Taxonomic variation in the structure of ‘punctuation calls’, visualized in RavenPro 1.5 (Cornell University). We recognize three groups based on shared acoustic structure: (Type 1) pulsed/rippling:C. [f.] hellmayri, Undescribed 1, C. [f.] mirabilis; (Type 2) long/sinuous: C. [f.] sanctaemartae, C. [f.] fuscater, C. [f.] berplepschi; (Type 3) short/simple: Undescribed 2, C. [f.] opertaneus, Undescribed 3, C. [f.] mentalis.

Figure 11. Taxonomic variation in the structure of ‘blurred calls’, visualized in RavenPro 1.5 (Cornell University). The black line divides calls that modulate upward in frequency (left) and downward in frequency (right); both types were detected in C. [f.] berlepschi.

Figure 12. Heat map showing frequency distributions of song contours within each population. Dyadic, triadic, and tetradic song contour names follow Fig.5. Single-note songs are shown in the first column (A) and songs with five or six notes were combined into a single category, shown in the last column (FIVESIX). Open (white) circles denote song contours that were not detected in C. [f.] hellmayri, despite it having a much larger sample size than other taxa. Closed (black) circles denote contours that were only detected in one taxon.

Figure 15. Ventral and dorsal views of the adult male plumages in C. b. berlepschi, C. b. caniceps, C. o.tenebris ssp. nov., C. b. nebulus ssp.nov., and C. mentalis. Photograph by M.R.H.

Figure 16. Ventral and dorsal views of the adult female plumages in C. b. berlepschi, C. b. caniceps, C. o.tenebris ssp. nov., C. b. nebulus ssp.nov., and C. mentalis. Photograph by M.R.H.