Omorgus (Omorgus) ciliatus ( Blanchard, 1847 )

da Costa-Silva, Vinícius, Strümpher, Werner P., Barclay, Maxwell V. L. & Vaz-de-Mello, Fernando Z., 2024, An illustrated catalogue of South American species of Omorgus Erichson, 1847 (Coleoptera, Trogidae, Omorginae) including a neotype designation and taxonomical changes, Contributions to Entomology 74 (1), pp. 81-101 : 81-101

Omorgus (Omorgus) ciliatus ( Blanchard, 1847)

Fig. 3

Trox ciliatus Blanchard, 1847: 190 (original description); Harold 1869: 1088 (catalogue); Harold 1872: 112 (redescription); Bruch 1911: 193 (checklist); Arrow 1912: 54 (catalogue); Blackwelder 1944: 218 (catalogue – as “ ciliata ”); Vaurie 1962: 152 (redescription).

Trox (Lagopelus) ciliatus : Burmeister 1876: 258, 265 (key and diagnosis); Preudhomme de Borre 1886: 59 (key and comments).

Trox (Omorgus) ciliatus : Scholtz 1982: 9 (catalogue).

Omorgus ciliatus : Scholtz 1990: 1405 (redescription); Diéguez and Gómez 2004: 94 (checklist); Deloya 2005: 122 (checklist); Gómez 2008: 514 (key for Argentinean species); Zidek 2013: 8 (checklist); Zidek 2017: 99 (checklist); Smith 2017: 85 (lectotype designation).

Omorgus lucidus Pittino, 2010 (new synonym); Zidek 2013: 12 (checklist); Zidek 2017: 103 (checklist).

Type specimen examined.

Lectotype ( MNHN). See Smith (2017: 2085) for high-quality images of the type specimen.

Type locality:

“ village the Patagones ” [= Viedna, Río Negro, Argentina].

Type specimen

of Omorgus (Omorgus) lucidus Pittino, 2010 (new synonym) examined. Holotype, by monotypy (♀ RPMI – Fig. 2 ). First label [white, Riccardo Pittino’s handwriting]: “ ARGENTINA / Buenos Ayres / ex Coll. Winkler ”. Second label [white with red border, Riccardo Pittino’s handwriting]: “ Omorgus ♀ / lucidus n. sp. / HOLOTYPUS / Det. R. Pittino 1980 ” (Fig. 2 C ). Type locality: “ Buenos Ayres ” [= Buenos Aires], Argentina.

Remarks.

Omorgus lucidus Pittino, 2010 was described to accommodate a single female specimen closely resembling Omorgus ciliatus ( Blanchard, 1847: 190) , from “ Buenos Ayres ” ( Argentina) (see Pittino 2010: 80). According to the author, both species are distinguished by “ several minor characters ” that include the form of clypeal edge, punctures of the forebody and elytral sculpture (which is visible in Omorgus ciliatus and without any trace of tubercle in Omorgus lucidus , according to the author). However, Trogidae species tend to show great intraspecific morphological variation (Costa-Silva, pers. communication) and we deem that Omorgus lucidus morphology falls within the intraspecific variability of O. ciliatus for the reasons specified below.

The diagnostic characteristics cited by Pittino (2010) to separate O. lucidus from O. ciliatus , include the shape of clypeal edge, punctures of the forebody and mainly the elytral sculpture. These features are dubious and, in our opinion, do not allow to confirm the validity of this species based on only a single female specimen, considering the morphological variation in Trogidae .

During an investigation of many South American and European collections, more than 170 specimens of proper O. ciliatus (according to the description provided by Scholtz 1990: 1405) were examined, being 25 males dissected to study. All specimens were studied considering the external and internal morphology, beyond the photographs of both type-species of O. lucidus (Fig. 2 ) and O. ciliatus (see Smith 2017: 2085).

In conclusion, we found a great variability in O. ciliatus for morphological characters used by Pittino (2010) as diagnostic for O. lucidus , as for example, the elytral sculpture (Fig. 3 A – F ). According to the author, the elytra of O. lucidus are “ scarcely convex with no tubercles ” and, after our study, we agree with the author’s statement. However, this character state is also found in a few specimens of O. ciliatus , as shown in Fig. 3 A – C , whose aedeagus was identical to the one of the more typical O. ciliatus (Fig. 3 G – I ). Therefore, we deem that Omorgus (Omorgus) lucidus Pittino, 2010 to be a junior subjective synonym of Omorgus (O.) ciliatus ( Blanchard, 1847) , that presents a wide distribution in Argentina.

Geographic distribution.

Argentina and Bolivia [?]. We have examined only one specimen at NHMUK, which bears a small label inscribed ‘ Bolivia’ and another label with the accession number ‘ 67-45 ’. This number corresponds to a data entry in the museum’s book, which refers to a donation made by Edward Wesley Janson (1822–1891) around 1867. This is probably the same specimen previously studied by Vaurie (1962). However, we treat this single record of Omorgus ciliatus from Bolivia with caution until new and reliable data becomes available.

Non-type examined material

(171 specimens). ARGENTINA – Buenos Aires, • 1; Baía Blanca ; C. Bruch leg.; MACN • 1; Carmen de Patagones ; MACN • 1; Medanos ; 11 Nov. 1946; Hayward y Willink leg.; IFML . – Catamarca • 2; 120 km N Belén ; 26 ° 59 ' 44 " S, 66 ° 18 ' 48 " W; 3 Fev. 2009; V. M. Diéguez & G. Arriagada leg.; CVMD • 4; Campo Posuelo , 60 km S Punta de Balasto; 8 Fev. 1997; G. Arriagada leg.; CVMD • 2; Punta Balasto ; 18 Jan. 1997; G. Arriagada leg.; CVMD • 2; Recreo ; Dec. 1928; IFML • 1; María ; 27 Fev. 1992; A. Ugarte leg.; NHMUK • 1; C. Bruch leg.; 1 MACN. – Chubut • 2; Biedma, Puerto Madryn , 4 km W costa; 42 ° 47 ' 8 " S, 65 ° 2 ' 56 " W; 11 Nov. 2011; G. Cheli leg.; IADIZA • 2; Estepa, Trelew ; 10 Apr. 2010; D. Rojas Lanus leg.; CVMD • 1; Paleontology Park Bryn Gwyn ; Apr. – May 2012; D. Rojas Lanus leg.; CVMD • 1; Península Valdes ; 1 Mar. 1998; D. Rojas Lanus leg.; CVMD • 1; Peninsula Valdés, Playa Colombo ; 12 Dec. 2001; D. Rojas Lanus leg.; CVMD • 1; Peninsula Valdés, Punta Pardelas ; 12 Dec. 2011; D. Rojas Lanus leg.; CVMD • 1; Pto. Madryn, Playa El Doradillo ; 23 Oct. 2011; D. Rojas Lanus leg.; CVMD . – Córdoba • 1; Río Cuarto, Las Albahacas ; 2 Nov. 2001; R. Gómez leg. CVMD . – La Pampa • 1; Curacó, Puelches, Estância La Gracielita ; 21 Oct. 2001; Bárbara Corró Molas leg.; IADIZA • 1; Curacó, Puelches, Estância La Gracielita ; 26 Nov. 2002; Bárbara Corró Molas leg.; IADIZA • 1; MACN. – La Rioja • 1; Mascasin ; Jan. 1959; CNC . – Mendoza • 6; 17 km E refugio Alvarado, Res. Laguna del Diamante ; 35 ° 15 ' 22 " S, 69 ° 12 ' 4 " W; 19 Nov. 2012; G. Arriágada leg.; CVMD • 1; Desaguadero ; 28–29 Fev. 2005; R. Barrera leg.; CVMD • 12; La Valle, Reserva de Telteca ; 8–10 Dec. 2002; V. M. Diéguez leg.; CVMD • 1; La Valle, Reserva de Telteca ; 9 Dec. 2002; R. Gómez leg. CVMD • 3; Lavalle, Telteca ; 10 Dec. 2002; G. Flores leg.; IADIZA • 1; Lavalle, Telteca ; 16–17 Dec. 2005; A. Marvaldi, R. Ruiz y G. Flores leg.; IADIZA • 3; Malargüe, Payunia ; 35 ° 40 ' 47 " S, 68 ° 41 ' 40 " W; 6 Jan. 2016; F. Aballay leg.; IADIZA • 8; Malargüe, Payunia ; 35 ° 59 ' 59 " S, 68 ° 52 ' 55 " W; 2 Dec. 2015; F. Aballay leg.; IADIZA • 2; Malargüe, Payunia, Mina Ethel ; 36 ° 0 ' 4 " S, 68 ° 50 ' 11 " W; 4 Jan. 2016; F. Aballay leg.; IADIZA • 4; San Carlos, Laguna del Diamante ; 31 Jan. 2016; F. Aballay & F. Jofré leg.; IADIZA • 36; San Carlos, Laguna del Diamante ; 31 Dec. 2015; F. Aballay & F. Jofré leg.; IADIZA • 1; San Rafael, “ El Sosneado ”; MACN • 1; Santa Rosa, Ñacuñan ; 15 Nov. 1996; G. Debandi leg.; IADIZA • 1; Santa Rosa, Ñacuñan ; 16 Fev. 1982; S. Claver leg.; IADIZA • 1; Santa Rosa, Ñacuñan ; 34 ° 2 ' 42 " S, 67 ° 54 ' 33 " W; 24 Oct. 2002; G. Debandi leg.; IADIZA • 1; Santa Rosa, Ñacuñan ; Jan. 1976; S. Roig leg.; IADIZA • 1; Santa Rosa, Ñacuñan , Nov. – Dec. 1998; S. Roig leg.; IADIZA • 12; Santa Rosa, Reserva de Ñacuñan ; 11–13 Dec. 2002; V. M. Diéguez leg.; IADIZA • 8; Santa Rosa, Reserva de Ñacuñan ; 8–10 Dec. 2002; V. M. Diéguez leg.; IADIZA • 1; Santa Rosa, Reserva Ñacuñan ; 10 Mar. 2014; G. Arriadaga leg.; CVMD • 2; Santa Rosa, Reserva Provincial Telteca ; 9 Dec. 2002; R. Gómez leg.; IFML • 1; Santa Rosa, Reserva Provincial Telteca ; 9 Dec. 2002; R. Gómez leg.; IADIZA • 1; MNHN • 1; Nov. 1946; Moyano leg.; IFML • 1; Dec. 1897; C. Bruch leg.; MACN . – Neuquén • 1; A. Breyer leg.; MACN • 1; Zapala; 12–22 Dec. 1946; Hayward y Willink leg.; IFML . – Río Negro • 1; Aguada Cecílio; MACN • 1; Río Colorado ; 13–19 Nov. 1946; Willink leg.; IFML • 3; Río Colorado ; Dec. 1990; CMNC • 3; A. Breyer leg.; MACN • 1; H. Richter leg.; MLPA • 1; Weiske leg.; MACN. – Salta • Anta, 33 km NE Joaquín Gonzales ; 22–28 Nov. 1979; Willink leg.; IFML • 1; Cachi ; MACN . – San Luis • 1; 30 Km NE San Luis ; Dec. 2009, P. Wegner leg.; CEMT • 3; Desaguadero ; 15–22 Jan. 1997; Jorge Jensen leg; CVMD • 1; Desaguadero , 8–19 Jan. 1996; E. Escobar leg.; CVMD • 1; San Jeronimo ; Jan. 1983; CMNC • 1; Santa Rosa ; Fev. 1998; Jaime Pizzaro leg.; IADIZA . – Santiago del Estero • 3; El Pinto ; Nov. 1956; CNC • 1; La Banda ; Oct. 1945; Briones leg.; CMNC . – Tucumán • 1; C. Bruch leg.; MACN .

BOLIVIA [?] – Without further locality • 1; NHMUK.

Figures

Figure 2. Holotype of Omorgus lucidus Pittino, 2010. A. Habitus in dorsal view; B. Habitus in lateral view; C. Labels. Photos by Alberto Ballerio (Brescia). Length of specimen: 13.8 mm.

Figure 3. Details of elytra, dorsal habitus and aedeagus of Omorgus ciliatus (Blanchard, 1847): A. Elytral tubercles present and visible (from Catamarca, Argentina); B. Poorly visible (Salta, Argentina) and C. Elytral tubercles absent (Neuquén). Habitus in dorsal view (D – F) of Omorgus ciliatus specimens and their respective aedeagus (G – I) showing no appreciable variation. Scale bars: 1 mm.