Pseudocanthon chaquensis Nazare-Silva & Silva 2021, new species
Creators: name: Nazaré-Silva, Everton E.
name: Silva, Fernando A. B.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Pseudocanthon
Pseudocanthon chaquensis

description: Pseudocanthon chaquensis Nazaré-Silva & Silva, new species   
(Figs. 1B, 1D, 2H, 3F 4E, 5F, 6F, 7B)  
urn:lsid:zoobank.org:act: 49764003-1A6D-4962-8B57-A968B9C4461B  
 Etymology. The specific name is a Latinization of the Spanish demonym “chaqueño”, which refers to the inhabitants of the Chaco region, the place where most of the known specimens were collected. It should be treated as a Latin third-declension adjective in the nominative case.   
 Diagnosis. Pseudocanthon chaquensis is similar to P. pantanensis in having the pronotum with dense, wellimpressed granulate microsculpture centrally (Fig. 2A); eighth stria of elytra extending to approximately anterior half of elytra, with shallow carina at anterior portion (Fig. 2D); and posterior edge of metafemur lightly angulate at basal third, expanded towards the abdominal ventrites (Figs 4E). However, P. chaquensis can be easily distinguished by having pygidium completely orange (Fig. 2H); parameres truncate apically, with small obtuse projection at ventral edge (Fig. 5F); frontolateral peripheral (FLP) endophallite elongate, bifurcate at inferior portion (Fig. 6F); accessory endophallite (AE) small and elongate (Fig. 6F). In P. pantanensis, the pygidium is metallic green and has an orange band at posterior edge (Fig. 2G); the parameres are curved and pointed apically (Fig. 5E); the frontolateral peripheral endophallite is sinuous, with inferior portion rounded (Fig. 6E); and the accessory endophallite is absent (Fig. 6E).   
 Description. Holotype. Length. 5.4 mm. Width. 3.3 mm. Colour. Surface of body dark brown with metallic green reflections; legs orange; orange spot on clypeus and on last abdominal ventrite. Surface punctation and sculpturing. In general, surface punctation consists of foveolate punctures. Surface of head, mesoventrite, metaventrite, elytra, abdomen, tibiae, and femora with dense and well-impressed granulate microsculpture; lateral edges and anterior angle of pronotum, hypomera, lateral edges, and anterior portion of metaventrite, mesepimeron, metanepisternum, epipleuron, tibiae, and femora with imbricate microsculpture. Pronotum with dense and wellimpressed granulate microsculpture centrally (Fig. 2A). Elytra. Eighth elytral stria extending across the basal half of the elytra, with shallow carina at basal portion (Fig. 2D). Legs. Posterior edge of metafemur lightly angulate at basal third, expanded towards at abdominal ventrites (Fig. 4E). Abdomen. Pygidium completely orange (Fig. 2H) Tegmen. Apex of parameres truncate, with small obtuse projection at ventral edge (Fig. 5F). Endophallus. Frontolateral peripheral (FLP) endophallite elongate, bifurcate at inferior portion (Fig. 6F); acessory endophallite (AE) small and elongate (Fig. 6F).   
 Type material. 14♀ and 23♂. Holotype. BRAZIL: MATO GROSSO: Poconé, Pousada Araras,[16°30’43.39’’S; 56°42’41.61’’W], 03.XII.1998, J. Moreno & T. Mestre — 1♂ (CEMT). Paratypes. BRAZIL: MATO GROSSO: Poconé, Pousada Araras, [16°30’43.39’’S; 56°42’41.61’’W], 03.XII.1998, J. Moreno & T. Mestre — 6♀ 17♂ (CEMT); Pirizal [pantanal region], [16°14’23.94’’S; 56°22’29.67’’W], 13.X.2007, pitfall, A. Tissiani — 1♀ 1♂ (CEMT). ARGENTINA: FORMOSA: [26°11’08.8’’S; 58°10’32.04’’W], 66 m, XII.1953, no collector — 1♂ (CMNC); Reserva Privada Estancia Guaycolec [woodland], [25°58’16.4’’S; 58°11’07.9’’W], 13.X.2015, rotten meat, A. Guerra — 1♀ (CEMT); CHACO: Resistencia, [27°27’06.7’’S; 58°59’08’’W], 58 m, XI.1945, no collector — 1♀ (CMNC); Resistencia [woodland], [27°30’26.9’’S; 59°05’03.5’’W], 54 m, 30.III.2016, pitfall, A. Raimundo — 3♀ 1♂ (CEMT); Resistencia [chaco region], [26°50’57.4’’S; 59°36’28.6’’W], 10.XI.2016, human feces, A. Guerra — 1♀ (CEMT). URUGUAY: CANELONES, San Luis, 18.IV.2000, P. Gonzalez — 1♂ (CEMT); San Luis, 23.III.2000, P. Gonzalez — 1♂ (CEMT).   
 Distribution. Known from Argentina (Chaco and Formosa) and Brazil (Mato Grosso) (Fig. 7B). Areas of endemism [South America]: Brazilian subregion: South Brazilian dominion: Rondônia province. Chacoan subregion: Chacoan dominion: Chaco province (see Morrone 2014: fig. 12).
description: Published as part of Nazaré-Silva, Everton E. & Silva, Fernando A. B., 2021, A taxonomic revision of the South American species of Pseudocanthon Bates, 1887 (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilini), pp. 61-86 in Zootaxa 5027 (1) on pages 76-82, DOI: 10.11646/zootaxa.5027.1.3, http://zenodo.org/record/5448088