Polynoncus aeger ( Guérin-Meneville, 1830 )

Costa-Silva, Vinícius, Strümpher, Werner P., Thyssen, Patricia J. & Vaz-de-Mello, Fernando Z., 2024, Taxonomic revision of the South American genus Polynoncus Burmeister, 1876 (Coleoptera: Scarabaeoidea: Trogidae), Journal of Natural History 58 (1 - 4), pp. 14-166 : 29-34

Polynoncus aeger ( Guérin-Meneville, 1830)

( Figures 6 , 8 )

Trox aeger Guérin-Meneville, 1830 : pl. 22 (validated name); Harold 1869: 1087 (checklist); Harold 1872: 132, 189 (redescription); Burmeister 1876: 259 (redescription); Berg 1881: 99 (checklist of Rio Negro, Argentina); Preudhomme de Borre 1886: 69 (checklist); Bruch 1911: 192 (checklist); Arrow 1912: 53 (catalogue); Blackwelder 1944: 218 (checklist – as ‘ aegra ’); Vaurie 1962: 120 (redescription)

Trox (Polynoncus) aeger : Scholtz 1982: 15 (catalogue)

Polynoncus aeger : Scholtz 1986a: 362 (systematics); Scholtz 1990: 1429 (redescription); Gómez 2008: 516 (key to Argentinean species); Zidek 2013: 6 (checklist); Ratcliffe et al. 2015: 189 (checklist from Peru); Zidek 2017: 97 (checklist); Smith 2017: 88 (lectotype designated); Costa-Silva and Diéguez 2020: 271 (records from Argentina)

Trox leprosus Blanchard, 1847: 188 (original description); Lacordaire 1856: 152 (checklist); Harold 1872: 132, 190 (checklist); Burmeister 1876: 259 (as synonym of T. aeger ); Preudhomme de Borre 1886: 73 (catalogue); Arrow 1912: 53 (catalogue – as junior synonym of T. aeger ); Vaurie 1962: 120 (as synonym of T. aeger ); Scholtz 1982: 15 (catalogue – as synonym of T. aeger ); Zidek 2013: 13 (checklist – as junior synonym of T. aeger ); Zidek 2017: 103 (checklist – as junior synonym of T. aeger ); Smith 2017: 88 (as junior synonym of T. aeger )

Type specimen examined. LECTOTYPE. ( MNHN – Figure 6 ) First label [white, aged, handwritten]: ‘ Trox / aeger Guer. / Lima’. Second label [white with black border, typeset]: ‘Ex-Musaeo / GUÉR-MENEV’. Third label [red with black border]: ‘ TROX / AEGER / Guérin-Méneville 1830 [Smith’s handwriting] / LECTOTYPE / A.B.T. SMITH’ ( Figure 6c ). Type locality: ‘Lima’ [ Peru?]. Although cited by some authors as Lima, possibly in Peru, the origins of the type series remain uncertain (see Smith 2017).

Type specimen examined of Trox leprosus Blanchard, 1847 . LECTOTYPE HERE DESIGNATED. ( MNHN – Figure 7 ) First label [white, aged, with black frame]: ‘MUSEUM PARIS / RIO-JANEIRO / D’ORBIGNY 1834’. Second label [round, Alcides d’Orbigny’s handwriting]: ‘5219 / 34’. Third label [white, aged, unknown handwriting]: ‘220’. Fourth label [green with black bars on each side, Émile Blanchard’s handwriting]: ‘leprosus . / Dj [Dejean]’. Fifth label [red with black frame, Vinícius Costa-Silva’s handwriting]: ‘ LECTOTYPE / Trox leprosus / Blanchard 1847 / des. V. Costa-Silva 2022’. Sixth label [white with black frame]: ‘= Polynoncus aeger / ( Guérin-Méneville 1830) / Det. V. Costa-Silva, 2022’ ( Figure 7c ).

Type locality. Maldonado ( Uruguay), collected by Alcides Dessalines d’Orbigny (1802– 1857) . The label ‘ Rio-Janeiro’ is incorrect according to the d’Orbigny catalogue: the number ‘220’ (third label) corresponds to the specimens collected on dried carrion (often found abundantly under the carcasses) in Maldonado ( Uruguay) during November 1826 .

Differential diagnosis. Polynoncus aeger is most similar to P. brevicollis and P. gibberosus but is easily separated from both by the presence of a distinct sub-humeral ridge (as in P. brasiliensis – Figure 14b , white arrows), and the basal tubercles not touching the pronotal ridges. Polynoncus brevicollis and P. gibberosus both lack the sub-humeral ridge and the basal tubercles touching the pronotal ridges. For a detailed description see Vaurie (1962, p. 120) and Scholtz (1990, p. 1429).

Geographic distribution. This species is known from the south-eastern part of Argentina, throughout Uruguay, and southern Brazil ( Figure 8 ).

Vaurie (1962) and Scholtz (1990), in their respective treatments of the Neotropical Trogidae , cited records of P. aeger from Chile. During this study, the first author (VCS) examined one specimen of P. aeger , housed in BMNH, with an old label written ‘Chili’ without further data. Based on our understanding about geographical distribution of P. aeger , we believe it is a mislabelled specimen. Furthermore, Diéguez (2008) in his revision of Chilean Trogidae concluded that both records by Vaurie (1962) and Scholtz (1990) were based in misidentified specimens of P. brevicollis (Eschscholtz) (see Diéguez 2008, p. 21). Since Diéguez’s study, no further records of P. aeger from Chile have been reported; hence, we agree that this species most likely does not occur in the country.

Scholtz (1990) also recorded P. aeger from the Amazonia region in Brazil (listing four specimens from Pará). We examined the four specimens lodged in the Carnegie Museum of Natural History (Pittsburgh, Pennsylvania, United States) mentioned by Scholtz (1990) . These specimens were most likely collected by Samuel Klages and later found their way into the Henry Klages Collection ( Nearns and Androw 2013) . The Henry Klages Collection is known to contain numerous mislabelled Nearctic and Neotropical specimens [Robert Androw, pers. comments to VCS] . Hence, we treat this record with caution. Vaurie (1962) also cited Peru for the distribution of P. aeger , probably because Guérin-Méneville (1844, p. 85), in his original description, cited ‘ Pérou’ as the type locality for this species based on the label reading ‘ Lima’. With the exception of the type cited by Guérin-Meneville, no other specimens have been recorded from this country. Considering the known geographical distribution of P. aeger , these records from Chile and Peru seem doubtful, and likely caused by mislabelling.

Examined non-type material (182 specimens). ARGENTINA: Buenos Aires, Androgué , February 1921, G. Pellerano leg. (1 MACN) ; Bahía Blanca,no date or collector (2 MACN) ; Bahía San Blas , 13 January 1829, A. d’Orbigny leg. (2 MNHN) ; Balcarce , no date, J.M. Gallardo leg. (1 MACN) ; Buenos Aires, Flores, 11 December 1918, no collector [Dallas’ collection] (1 MLPA) ; Buenos Aires, Flores, 8 April 1919, no collector [Bosq’s collection] (1 MLPA) ; Buenos Aires, Flores, 9 April 1919, no collector [Bosq’s collection] (1 MLPA) ; Buenos Aires, Villa Mazzini, 15 December 1910, no collector [Bosq’s collection] (1 MLPA) ; Burzaco, 15 October 1939, no collector (1 CVMD) ; Caseros, 15 January 1946, no collector (1 MACN) ; Gorchs , March 1917, G. Pellerano leg. (1 MACN) ; La Plata , 1906, L. Fairmaire leg. (1♂ MNHN) ; La Plata, Manuel Bernardo Gonnet , 13 December 1957, H.E. Trotta leg. (1 MLPA) ; La Plata, no date or collector (1 MACN) ; La Plata, no date or collector (3 MLPA) ; La Plata, no date or collector (2 CEMT) ; La Plata , no date, C. Bruch leg. (5 MLPA) ; La Plata, Rio Santiago , 15 December 1907, C. Bruch leg. (1 MACN) ; La Plata, Tolosa, no date or collector (1 MACN) ; La Plata, W. Warren leg. (1 BMNH) ; [La] Plata, no date or collector (2 MNHN) ; Rosas , ‘F.C. Sud’ [Ferrocarril al Sud – Train Station], no date, J.B. Daguerre leg. (2 MACN) ; Tandil , January 1951, no collector (1 MLPA) ; Tornquist, Sierra de la Ventana, no date or collector (1 CEMT) ; without specific locality, 1 October 1903, A. Zotta leg. (1 MACN) ; without specific locality, 14 April 1905, no collector [Bruch’s collection] (1 MACN) ; without specific locality, 1922, L. Bedel leg. (1 MNHN) ; without specific locality, date or collector (1♂ and 3 unsexed BMNH) ; without specific locality, date or collector (2 MNHN) ; without specific locality, date or collector (3 MACN) ; without specific locality, date or collector (3 MLPA) ; without specific locality, date or collector [ Richter’s collection] (3 MLPA) ; without specific locality or date, A. Beyer leg. (1 MACN) ; without specific locality or date, A. Beyer leg. (3 MACN) ; without specific locality or date, A. Zotta leg. (1 MACN). Córdoba, Calamuchita, Hotel El Sauce , June 1976, M. Viana leg. (2♂ and 11 unsexed CVMD) ; Cruz Alta , June 1941, J.P. Duret leg. (1 MNHN) ; Fauna Nature Reserve Laguna La Felipa, 24 November 2003, cow carcass, no collector (1 IFML) ; Fauna Nature Reserve Laguna La Felipa, 33.140°S, 63.535°W, 24 November 2003, cow carcass, no collector (1 MNHN) ; Laguna La Helvecia , 20 January 2003, cow carcass, R. Gomez leg. (1 IADIZA) ; Villla Carlos Paz , January 1954, no collector (1 MLPA) ; without specific locality or date, P.G. Lorentz leg. (1 MNHN) ; without specific locality, date or collector (2 MLPA) ; without specific locality, September 1947, no collector (1 MACN). Corrientes, Santo Tomé , November 1926, G. Pellerano leg. (1 MACN) ; without specific locality, date or collector (1 MACN). Entre Rios, Paraná, no date or collector [Burmeister’s collection] (2 MACN) ; Pueblo Liebig , 10–17 December 1994, G. Arriagada leg. (1 CVMD) ; Pueblo Liebig , December 1997, Mateo Zelich leg. (1♂ and 3 unsexed CVMD) ; Villa del Rosário , no date, A. Stevenin leg. (1 MACN) ; Villa Paranacito, no date or collector (1 MACN) ; without specific locality, date or collector [ Richter’s collection] (1 MLPA). La Pampa, Santa Rosa , 29 August 1997, Alfageme leg. (1♀ IADIZA) ; Toay, Parque Luro Provincial Reserve , 10 December 1997, D. Rojas Lanus leg. (1♂ CVMD). La Rioja, without specific locality, date or collector (3 MACN). Misiones, without specific locality, date or collector (3 MLPA) ; without specific locality or date, A. Beyer leg. (1 MACN). San Luis, Villa Elena Natural Reserve , November 1976, M. Viana leg. (2♂ and 29 unsexed CVMD) ; Villa Elena Natural Reserve , November 1976, M. Viana leg. (1 MUSM). Santa Fé, Rosário, no date or collector (1 MACN) ; without specific locality, 1900, no collector [Bruch’s collection] (1 MACN) ; without specific locality, date or collector [ Richter’s collection] (2 MLPA). Without specific locality, date or collector (1 MLPA) ; without specific locality or date, C. Berg leg. (2 MNHN). BRAZIL: Pará [dubious locality] ( CMNH). Paraná, Guarapuava , October 1957, H. Scheneider leg. (1 MZSP). Rio Grande do Sul, CanguÇu, Cabanha Sobrado Branco , 300 m, April 2012, Light trap, Santos Dias, Carneiro and Zacca leg. (1♀ CEMT) ; Pelotas , 4 February 1961, Biezanko leg. (1 CVMD) ; Rio Grande, Taim Ecological Station , 14–15 September 1991, L. Moura leg. (1 MCNZ) ; Rio Grande, Taim Ecological Station , 5 November 1986, A. Lise leg. (1 MCNZ) ; without specific locality, date or collector (1 MNHN). Santa Catarina, BR 116, 4 February 1969, L. Stange leg. (1 IFML). Without specific locality, date or collector (1 MNHN) ; without specific locality, date or collector (1 BMNH). CHILE [dubious locality]: without specific locality, date or collector (1 BMNH). URUGUAY: Canelones, Las Piedras , 18 January 1968, A. Carmenes leg. (1♂ CVMD). Cerro Largo, Cañada de los Burros, 1908, T. Lucas leg. [Tremoleras’ collection] (2 MLPA). Colônia, La Estanzuela , INIA [National Institute of Agricultural Research], 12 September 1995, J.R. Verdú leg. (1♂ and 1♀ CEMT) ; without specific locality, 20 January 1924, J. Tremoleras leg. [Tremoleras’ collection] (1 MLPA) ; without specific locality, date or collector (1 MACN). Montevideo, Colón, 3 November 1931, no collector [Tremoleras’ collection] (1 MLPA) ; Colón , 10 November 1932, E. Montoro Guarch [ex-Tremoleras’ collection] leg. (1 CEMT) ; Colón , May 1896, M.G. Oldfield Thomas leg. (1 BMNH) ; Pocitos , 13 October 1932, no collector [Tremoleras’ collection] (1 MLPA) ; without specific locality or date, Birabent leg. (2 MNHN) ; without specific locality, 24 December 1931, no collector [Tremoleras’ collection] (2 MLPA) ; without specific locality, date or collector (2 MNHN) ; without specific locality, date or collector [Tremoleras’ collection] (1 MLPA). Paysandú, Paysandú, no date or collector (3 MNHN). Rivera, Valle del Lunarejo, Arroyo Gajo del Lunarejo, 29 July 1995, no collector (4 MZSP). Rocha, Rocha, no date or collector (1 MACN). Without specific locality, date or collector (5 MNHN) .

Remarks. Polynoncus aeger was described by Félix Édouard Guérin-Méneville (1799– 1874), historically dated to 1844 by several authors (ie Arrow 1912; Blackwelder 1944; Vaurie 1962; Scholtz 1982, 1990; Zidek 2013, 2017). However, as noticed by Smith (2017), P. aeger was illustrated in livraison 9, pl. 22 of the Guérin-Méneville work. This section refers to the date of 1930 and should be used as the correct year of publication for this species as defined by the International Code of Zoological Nomenclature (ICZN, 1999, p. 102; see also Bousquet 2016, p. 234).

Figures

Figure 6. Lectotype of Trox aeger Guérin-Meneville, 1830 (now Polynoncus aeger): habitus in a, dorsal and b, lateral view; c, labels. Scale bar: 1 mm.

Figure 7. Lectotype of Trox leprosus Blanchard, 1847 (= Polynoncus aeger), here designated: habitus in a, dorsal and b, lateral view; c, labels. Scale bar: 1 mm.

Figure 8. Distribution map of Polynoncus aeger (red circles), P. aricensis (green triangles), and P. diffluens (blue squares) in South America. The records with a black dot in the centre indicate the type locality of the respective species.? = dubious record.

Figure 14. Holotype of Trox brasiliensis Vaurie, 1962 (now Polynoncus brasiliensis): habitus in a, dorsal and b, lateral view (white arrows showing the subhumeral edge); c, male genitalia in dorsal view; d, labels. Photos by Rafael Sousa (MZSP). Length of specimen: 11 mm.