Polynoncus longitarsis ( Harold, 1872 )

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 : 103-105

Polynoncus longitarsis ( Harold, 1872)

( Figures 4b , 25 , 43 )

Trox longitarsis Harold, 1872: 136 , 190 (original description); Preudhomme de Borre 1886: 73 (checklist); Arrow 1912: 58 (catalogue); Blackwelder 1944: 219 (checklist); Vaurie 1962: 137

Trox (Polynoncus) longitarsis : Scholtz 1982: 16 (catalogue)

Polynoncus longitarsis : Scholtz 1986a: 362 (systematics); Scholtz 1990: 1451 (redescription); Gómez 2008: 516 (key to Argentinean species); Zidek 2013: 12 (checklist); Zidek 2017: 103 (checklist); Smith 2017: 97 (distribution data); Costa-Silva and Diéguez 2020: 272 (records from Argentina); Mondaca 2023: 210 (checklist from Chile)

Type specimen examined. HOLOTYPE. ( MNHN – Figure 43 ) First label [white, aged, Edgar von Harold’s handwriting]: ‘Chili / longitarsis / mihi. / typ’. Second label [white, aged, with black border, typeset]: ‘Ex-Musaeo / E. Harold’. Third label [red, printed]: ‘TYPE’. Fourth label [red with black border, Andrew Smith’s handwriting]: ‘ TROX / LONGITARSIS / Harold 1872 / HOLOTYPE’. Fifth label [white, printed]: ‘[QR Code] / SCARABS OF / SOUTHERN / SOUTH AMERICA / SSS3001569’ ( Figure 43c ). Type locality: ‘Chili’ ( Chile), without specific locality.

Differential diagnosis. Polynoncus longitarsis is similar to P. mirabilis and P. chilensis in external morphology. It can be reliably distinguished from both species by having elongate and shiny elytral tubercles and intercostal punctures well-defined and deep (better visible in clean specimens). In P. mirabilis and P. chilensis , the elytral tubercles are elongated and distinctly raised and many tubercles have the surface covered by tomentum.The morphology of the male genitalia is also diagnostic: P. longitarsis has the apex of parameres without sclerotisation and bowed down, giving an impression of the truncate apex in dorsal view, while in P. mirabilis and P. chilensis , the apex of parameres is distinctively sclerotised.

Geographic distribution. Polynoncus longitarsis is recorded in arid zones of southern Chile and Argentine Patagonia ( Figure 25 ). These records match with the geographical distribution previously reported for this species (ie Vaurie 1962; Scholtz 1990; Diéguez 2008; Smith 2017; Costa-Silva and Diéguez 2020).

Examined non-type material (76 specimens). ARGENTINA: Neuquén, 32 km E of Paso Hua-Hum, Lago Lácar , 950 m, 40.133°S, 71.433°W, 11 January 1988, pitfall trap with human dung, Ashworth, Fugiseth, Maliscke leg . (1♂ CEMT); Chapelco , 10 November 1981, Mario Gentili leg . (1 IADIZA); Nonthué, Lago Lácar , 640 m, 17 October 1990, Mario Gentili leg . (1 CEMT); Nonthué, Lago Lácar , 640 m, 17 October 1990, Mario Gentili leg . (1♂ IADIZA); Nonthué, Lago Lácar , 640 m, 30 December 1992, Mario Gentili leg . (1 IADIZA); Nonthué, Lago Lácar , 640 m, 7 November 1982, Mario Gentili leg .(1♂ and 1 unsexed IADIZA); Quilaquina, 1000 m, no date or collector (1♂ IADIZA); San Martin de los Andes , 6–7 November 1948, Hayward y Willink leg . (1 IFML); San Martín de los Andes, Pucará , October 1952, S . Schajovskoy leg . [Schajovskoy’s collection] (1 MLPA); Yuco, Lago Lácar , 950 m, 25 November 1983, Mario Gentili leg . (1♂ IADIZA) . Río Negro, São Carlos de Bariloche , January 1965, A . Martinez leg . (3 MZSP). CHILE: Araucanía (IX Region), Curacautin, Cuesta Las Raíces , December 1999, A . Ugarte leg . (1 CVMD); Lonquimay , February 1994, S . Castro leg . (1 CVMD); Mala’cahuello, Malalcahuello Natural Reserve , January 2000, A . Ugarte leg . (1 CVMD). Bío-Bío (VIII Region), Alto Cayucupil , 25–31 January 1997, V .M . Diéguez leg . (1♂ and 1 unsexed CVMD); Chillan Los Lleuques , 12 January 1994, S . Castro leg . (2 CVMD); Los Angeles, November 1921, no collector (1 MZSP); Ñuble, Puente Marchant , 6–8 December 1997, V .M . Diéguez leg. (1 CVMD). Los Lagos (X Region), Isla de Chiloé, Quellón , January 1951, J .S . Vargas leg . (1 MNNC); Llanquihue, Saltos del Petrohue 150 m, 23 December 1984, Peck leg . (1 MCNZ); Palena , 37 km SE Chaitén, 60 m, 28 December 1984 – 30 January 1985, S . and J . Peck leg . (3 BMNH); Paso Carririñe, 1–7 February 1999, V .M . Diéguez leg . (1 CVMD); Puerto Montt , Fundo El Mirador 3 December 2010, cattle carcass,V .M . Diéguez leg . (1♂ CVMD); Puerto Montt , Fundo El Mirador, 25 January 2005, cattle carcass,V .M .Diéguez leg . (4 CVMD); Purranque , 10 km N, 40.850°S, 73.183°W, 24 October 1990, pitfall trapwith faeces as bait, Endrödy-Younga leg . (1 TMSA); Puyehue National Park , 400 m, 24–31 January 2004, Light trap, V .M . Diéguez leg. (1 CVMD). Los Ríos (XIV Region), Los Valdivia , Santo Domingo , 23 September 1990, E . Krahmer leg . (2♂ CEMT); Puyehue Volcano , 260 m, 40.633°S, 72.200°W, 18 November 1990, pitfall trap with faeces as bait, Endrödy-Younga leg . (24 TMSA); Valdivia , 10–12 January 1980, E . Krahmer leg . (1 MNNC); Valdivia , 17 December 1993, S . Castro leg . (1 MUSM); Valdivia , December 1994, S . Castro leg . (2 CVMD); Valdivia , 17 December 1993, S . Castro leg . (3 CVMD); Valdivia, 19 March 2007, no collector (3 CEMT); Valdivia, Corral , December 1994, L . Peña leg . (1 BMNH). Without specific locality, date or collector (2 MNHN); without specific locality, date or collector (1♀ BMNH) .

Figures

Figure 4. Differential morphology in Polynoncus spp.: a, without humeral callus [P. hemisphaericus]; b, with humeral callus [P. longitarsis]. Apex of mesotibia c, with tooth [P. peruanus] and d, without tooth (white arrow) [P. crypticus]. Posterior margin of clypeus e, emarginate [P. bullatus] and f, truncate (white arrow) [P. hemisphaericus]; pronotal ridges of pronotum in g, Polynoncus argentinus and h, Polynoncus pseudogemmifer sp. n. (paratype). Scale bar: 1 mm.

Figure 25. Distribution map of Polynoncus ecuadorensis (red circles), P. longitarsis (green triangles), and P. pampeanus (blue squares) in South America. The records with a black dot in the centre indicate the type locality of the respective species.

Figure 43. Holotype of Trox longitarsis Harold, 1872 (now Polynoncus longitarsis): habitus in a, dorsal and b, lateral view; c, labels. Scale bar: 1 mm.