Balleriolus, Sousa & Vaz-de-Mello, 2023

Sousa, Rafael & Vaz-de-Mello, Fernando Z., 2023, Balleriolus, a new termitophilous genus of Ceratocanthinae (Coleoptera: Hybosoridae) from South America and notes on termitophily in the tribe Scarabatermitini, Journal of Natural History 57 (29 - 32), pp. 1377-1395 : 1380-1386

publication ID	https://doi.org/ 10.1080/00222933.2023.2248689
DOI	https://doi.org/10.5281/zenodo.10492208
persistent identifier	https://treatment.plazi.org/id/18494973-FF86-FF8A-FD97-25E20A5AFAA7
treatment provided by	Plazi
scientific name	Balleriolus
status	gen. nov.

Treatment

Balleriolus View in CoL gen. n.

( Figures 1A–N View Figure 1 , 2 A–E View Figure 2 , 3 E View Figure 3 , 4 A, B, E, F, H, I, M, N View Figure 4 , 5B, C View Figure 5 )

Type species. Balleriolus howdeni View in CoL sp. n. (here designated).

Differential diagnosis. Balleriolus gen. n. morphologically resembles Ivieolus Howden and Gill, 1988 . On the pronotum both genera have a deep U- or V-shaped sulcus on the median posterior area, but Balleriolus gen. n. can be distinguished by the following combination of morphological characteristics ( Ivieolus morphology in parentheses): mandibles with 1 apical tooth ( Figures 1M, N View Figure 1 , 3H View Figure 3 ) (2 distinct apical teeth, Figure 3G View Figure 3 ); maxillary palpus slender (robust), distal palpomere subpiriform ( Figures 1M, N View Figure 1 , 3H View Figure 3 , 4B View Figure 4 ) (piriform, Figure 3B, C, G View Figure 3 ); labium with 3 palpomeres ( Figure 3H View Figure 3 ) (1 palpomere, Figure 3G View Figure 3 ), palpus small and cylindrical ( Figure 3H View Figure 3 ) (large and nearly spherical, Figure 3G View Figure 3 ); sides of pronotum not constricted ( Figures 1 View Figure 1 , 4A, B View Figure 4 ) (medially constricted, Figures 3A–F View Figure 3 , 4C, D View Figure 4 ); posterior area of pseudoscutellum not separated from posterior border of pronotum by a margin ( Figure 4A, B View Figure 4 ) (separated from posterior margin of pronotum, Figure 4C, D View Figure 4 ) (see Table 2 View Table 2 ).

Description. Body. Length 4.5–5.5 mm; width 1.5–1.9 mm; body form elongated. Head. Clypeus wide, lateral margin slightly rounded and contiguous with the gena, junction slightly rounded ( Figure 1M, N View Figure 1 ); anterior area of mandibles, labrum and palps extending anteriorly to clypeus anterior margin. Mandibles with 1 tooth, anteriorly sclerotised ( Figures 1M, N View Figure 1 , 3H View Figure 3 ). Maxillae with 3 slender palpomeres; distal palp subpiriform ( Figures 1M, N View Figure 1 , 3H View Figure 3 , 4B View Figure 4 ). Mentum small and slightly convex ( Figure 3H View Figure 3 ); labial palpus with 3 small and cylindrical palpomeres ( Figure 3H View Figure 3 ). Antennae with 8 antennomeres; scape slightly flattened, longer than funicle (antennomeres III–V, Figure 1M, N View Figure 1 ), proximal area narrow and sinuated; pedicel cylindrical; antennomere III smaller than IV–V; club composed by 3 antennomeres, distal lamella convex and smaller than proximal and medial lamella, medial lamella slenderer than others ( Figures 1M, N View Figure 1 , 3H View Figure 3 , 4A, B View Figure 4 ). Thorax. Median posterior area of pronotum with a large and deep inverted U-shaped sulcus delimiting the pseudoscutellum; posterior area of pseudoscutellum convergent and not separated from posterior margin of pronotum ( Figures 1 View Figure 1 , 4A, B View Figure 4 ). Legs. Procoxa subcontiguous, conical ( Figure 3H View Figure 3 ); protibia with 2 acute outer teeth; distal tooth slightly unciform; spur indistinct ( Figure 4I, J View Figure 4 ); tarsomeres setose laterally, cylindrical and slightly expanded distally ( Figure 4I, J View Figure 4 ); tarsomeres I and V longer than II–IV; tarsal claws simple and symmetrical. Meso- and metacoxae contiguous; meso- and metafemora slender; meso- and metatibia with 2 long and simple spurs; metatarsomeres with ventral setae more robust than the dorsal setae. Abdomen. Visible sternites conical ( Figures 1F, G View Figure 1 , 2B, C View Figure 2 ).

Etymology. The genus is named after Dr Alberto Ballerio, who has dedicated many years to the study of the taxonomy and systematics of Ceratocanthinae . The gender of the name is masculine.