Taxonomic revision and notes on natural history of the enigmatic beetle genus Gibboryctes Endrödi (Coleoptera: Melolonthidae: Dynastinae) Author Costa, Leidiane O. Author Duarte, Paulo R. M. Author Iannuzzi, Luciana Author Grossi, Paschoal C. text Journal of Natural History 2022 2022-05-17 56 1 - 4 191 225 http://dx.doi.org/10.1080/00222933.2021.2017499 journal article 82886 10.1080/00222933.2021.2017499 5cd01cfe-52bb-4092-97b2-804c3c7d145d 1464-5262 6758313 D766FC5E-CEC8-4184-BE90-C25350B90612 Gibboryctes szelenyii Endrödi, 1974 ( Figures 1 ; 6 (a); 7(a); 8(a); 9(a); 10(a–b); 11(a); 12(a–b); 13(a); 14(b); 15; 16) Gibboryctes szelenyii . Endrödi 1974: 14 Diagnosis Gibboryctes szelenyii differs from the other two Gibboryctes species by the following combination of characters: labrum subtriangular, weakly rounded on apical margin ( Figure 6 (a)); maxillary galea triangular ( Figure 8 (a)); punctures on pronotal anterior corners predominantly contiguous ( Figures 9 (a) and Figures 12 (a)); elytral interstriae densely covered with large punctures ( Figure 12 (b)). Figure 11. Detail of head, pronotum and prothoracic legs of females in dorsal view: (a) Gibboryctes szelenyii Endrödi ; (b) Gibboryctes ebeninus sp. nov. ; (c) Gibboryctes endroedi sp. nov. ; (d) Heterogomphus gracilicornis Prell ; (e) Tetragus waldenfelsi (Endrödi) . Arrow indicates punctate frons in (b). Type material ( Figure 1 (a–c)) Holotype male, labelled: (a) ‘ Holotypus / Gibboryctes / szelenyii /Endr’. [old white label, bordered in red, partially handwritten]; (b) ‘Vidit 1976/R. -P. Dechambre’ [white label, partially handwritten]; (c) ‘Paraguay’ [old white label, handwritten] ( MNHM ). Figure 12. Females of Gibboryctes species with detail of head, pronotum and prothoracic legs in lateral view and left elytra in dorsal view, respectively. (a,b) Gibboryctes szelenyii Endrödi ; (c,d) Gibboryctes ebeninus sp. nov. ; (e,f) Gibboryctes endroedii sp. nov. Jsi, juxtasutural interstria. Arrow indicates coalescent punctures in (e). Non-type material BRAZIL : Brasília , Distrito Federal , Brazlândia , Fazenda São Joaquim , January 2004 , luz, E.J. Grossi and P.C. Grossi legs . – 1 female ( CERPE ). Paraná , Tibagi , Parque Estadual do Guartelá , 28–30 October 2011 , Grossi , Parizotto , Leivas and Santos – 7 males , 5 females ( CERPE , CE-UFPE and EPGC ); November 2012 , breed, Grossi and Parizotto – 1 male , 1 female ( CERPE ); December 2010 , 900 m, breeding in Nasutitermis sp., Grossi and Parizotto – 1 male , 1 female ( CERPE ). Ponta Grossa , Parque Estadual de Vila Velha , 12 December 2011 , breeding in Nasutitermis sp., Grossi and Parizotto – 1 male , 4 females ( CERPE ); Faz . S. Damásio , 1 Novvember 2007, 1088 m , 24.6290°S , 50.2152°W , breeding in Nasutitermis sp., Grossi and Parizotto – 5 males , 4 females ( CERPE ) . No data – 1 male , 1 female ( EPGC ) . Figure 13. Detail of ventrites I–VI of females. (a) Gibboryctes szelenyii Endrödi ; (b) Gibboryctes ebeninus sp. nov ; (c) Gibboryctes endroedii sp. nov. ; (d) Tetragus waldenfelsi (Endrödi) . Red arrows indicate the proportions of ventrites V and VI. Male ( Figure 1 (d,e)) Redescription. Length : 24.4–35.6 mm . Width : 10.9–15.3 mm . Colour : From reddish brown to dark reddish brown. Head : Clypeus subtriangular, transverse, slightly constricted laterally towards a bidentate (teeth inconspicuous) anterior margin; lateral margins slightly produced posteriorly; surface rugopunctate, with 2 moderately setose areas on sides. Frontoclypeal suture with a transverse, flattened, subtrapezoidal tubercle; tubercle sometimes emarginate at middle, scarcely setose laterally. Frons from flattened to slightly concave, glabrous, transversely rugopunctate; punctures large, deep, coalescent; interocular width equals 4.63 times transverse eye diameter. Ocular canthus transverse, subrectangular; anterior margin slightly arched; outer corner usually pointed. Antennae : Club subequal in length to antenomeres II–VII combined. Mouthparts : Labrum subtriangular, weakly rounded at apical margin, densely covered with a fringe of bristles dorsally ( Figure 6 (a)). Mandibles with 2 lobed teeth separated by a shallow, wide notch ( Figure 7 (a)). Maxilla with triangular galea ( Figure 8 (a)); inner margin with 2–3 small teeth; stipe laterally expanded in triangular shape. Labium oval, surrounded with large, deep, coalescent bristled punctures; discal area with bristled punctures scattered about 3 diameters of punctures. Thorax : Pronotum with complete borders in dorsal view; middle area close to anterior margin with a small, transverse tubercle; dorsal surface densely punctate; anterior corners with large, deep, contiguous punctures ( Figure 9 (a)); lateral punctures large, deep, from contiguous to separate about 1 diameter of punctures; punctures gradually becoming small, shallow, sparser towards posterior area. Scutellar plate usually subtriangular, anteriorly covered with deep, large, irregularly scattered punctures. Elytral surface usually with 9 well-marked striae; each stria covered with large, deep, ocellate, contiguous punctures; interstriae with mixed fine and large punctures, irregularly scattered from anterior to posterior elytral area. Legs : Protibial outer margin with 4 triangular teeth (1 apical, 2 medial, 1 basal); apical tooth curved; first medial tooth tooth larger compared to other teeth; basal tooth smaller than previous ones. Mesotibial outer carinae and apex covered with stout spinules like setae (3–4 on basal carina, 4–6 on medial carina, 7–10 on apex). Mesofemora surbectangular, moderately setose ventrally on disc. Metatibial basal carina usually with 3 spinules; medial carina with 8–12 stout spinules; apex bordered with 8–10 spinules. Metafemoral ventral surface glabrous on disc, scarcely covered with shallow punctures. Abdomen : Tergite 8 strongly convex in lateral view; surface densely covered with large, deep punctures, from coalescent to contiguous. Ventrites 2–5 rugopunctate on sides, scarcely punctate on disc; area near to posterior margin with an incomplete row of setae confined on sides, disc glabrous; ventrite VI emarginate at middle posteriorly, transversely rugose anteriorly, rugopunctate on sides, finely punctate on disc; posterior margin setose. Venter : Prosternal process wide, rounded apically. Mesoventrite completely rugopunctate, densely setose. Metaventral surface nearly completely setose, smooth on a transversal middle area at disc. Aedeagus : Parameres, in dorsal view, finely punctate, divergent and wide at basal half, convergent and narrow at apical half, scarcely bristled at inner margin of apex ( Figure 10 (a)). Parameres, in lateral view, arched dorsally, ventrally bearing a middle carina, apex slightly rounded ( Figure 10 (b)). Figure 14. Geographic distribution maps. (a) Tetragus species ; (b) Gibboryctes species ; (c) Heterogomphus gracilicornis Prell. Figure 15. (a) Rupestrian grassland; (b) rock outcrops. Figure 16. (a) Adult of Gibboryctes szelenyii Endrödi at central portion of termite nest (arrow); (b) detail of the adult in situ (arrow); (c) pupal chamber with its structures in the shape of pellets (arrow); (d) recently emerged adult. Female ( Figure 1 (f)) Redescription. Length : 28.1–35.5 mm . Width : 10.9–15.7 mm . Quite similar to male, except in the following aspects: Head : Clypeus slightly rounded anteriorly ( Figure 11 (a)). Abdomen : Tergite VIII weakly convex in lateral view; ventrite VI parabolic in shape, not emarginate at middle of posterior margin ( Figure 13 (a)). Geographic distribution ( Figure 14 (b)) Paraguay , with no further data; Brazil ( Paraná , Distrito Federal), new country record. Remarks For a long time, no other record of G. szelenyii had been made since the species description by Endrödi (1974) , only the type specimen being known – and without accurate locality data – from Paraguay . The species is recorded for the first time from Brazil in this study, where 30 specimens were collected in termite nests within the Campos Gerais region, located at the second Parana plateau ( Figure 15 (a,b)). The termites sampled were probably occupying an old termite nest of another species, and were themselves identified as belonging to multiple genera and species (R. Constantino pers. comm., 2011) as follows: Diversitermes diversimiles (Silvestri, 1901) , Neocapritermes opacus (Hagen, 1858) , Nasutitermes coxipoensis (Holmgren, 1910) , Anoplotermes sp. and Grigiotermes sp.