Omorgus (Haroldomorgus) batesi (Harold, 1872)

Trox batesi Harold, 1872: 126 (original description); Arrow 1912: 54 (catalogue); Blackwelder 1944: 218 (catalogue); Vaurie 1962: 154 (redescription).

Trox (Omorgus) batesi: Scholtz 1982: 8 (catalogue).

Omorgus (Haroldomorgus) batesi: Scholtz 1986 a: 362 (phylogenetics); Scholtz 1990: 1418 (redescription); Zidek 2013: 7 (catalogue); Strümpher et al. 2014: 549 (systematics); Strümpher et al. 2016: 62 (systematics); Zidek 2017: 98 (catalogue); Hielkema and Hielkema 2019: 10 (checklist for the Guianas); Costa-Silva et al. 2021: 1997 (review of Brazilian species).

Omorgus batesi: Deloya 2005: 122 (checklist).

Type specimen examined.

Holotype (♂ MNHN). See Costa-Silva et al. (2021: 1997) for high-quality images of the type specimen. Type locality: “ Amazonestrom ” [Amazonas River].

Geographic distribution.

Argentina, Bolivia, Brazil and Paraguay (Zidek 2017; Costa-Silva et al. 2021).

Non-type examined material

(four specimens additionally to Scholtz (1990) and Costa-Silva et al. (2021)). BRAZIL – Amazonas • 1; Parana da Eva; 8 Nov. 1969; J. M. & B. A. Campbell leg.; CNC . – Mato Grosso • 1; Juina; 1 Oct. 2022; K. R. Ferreira leg; CEMT • 1; Santa Cruz do Xingu, Faz. da Ilha; 9 ° 45 ' 41 " S, 52 ° 15 ' 41 " W; UV light trap; 11–17 Jan. 2024; D. F. Rodrigues & T. I. Vitor-da-Silva leg.; CEMT . – Rio de Janeiro • 1 ♀; Magé, 70 km N [north] of Rio de Janeiro; 15 Oct. – 10 Nov. 1999; W. Grosser leg.; NHMUK .

Note.

The monotypic subgenus Haroldomorgus Scholtz, 1986 a was established to accommodate Trox batesi Harold, 1872, following a morphological phylogenetic analysis aimed at elucidating the suprageneric relationships within Trogidae (refer to Scholtz, 1986 a for details). One of the most distinctive features of Omorgus (Haroldomorgus) species is a complete absence of tubercles or ridges on the pronotum and elytra. Additionally, this species exhibits an oval-shaped scutellum that is not constricted at the base, which distinguishes it from the typical modern concept of Omorgus species. Following a morphological phylogenetic analysis conducted by some of the authors (VCS, WPS, and FZVM – Costa-Silva et al. in press), the genus Omorgus was recovered to be paraphyletic, restoring Haroldomorgus as a sister group to Omorgus + Polynoncus . In the first and only molecular phylogeny of Trogidae performed to date, by Strümpher et al. (2014), no specimens of Omorgus (Haroldomorgus) batesi were used in the analysis. However, we have now obtained fresh specimens to revisit the molecular analysis and finally test the Scholtz’s (1986 a) hypothesis and the position of Haroldomorgus within Trogidae .