Taxonomic revision of the Deltohyboma Lane, 1946 gilli species group (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilum) Author González-Alvarado, Arturo 2D58A702-73A9-4C66-8CED-6B8B9A2AB10B Programa de Pós-graduação em Ecologia e Conservação da Biodiversidade, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. fagakorn@gmail.com Author Vaz-De, Fernando Z. 2FF2B7D6-1A6B-43C1-9966-A1A949FB2B05 Instituto de Biociências, Departamento de Biologia e Zoologia, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. vazdemello@gmail.com text European Journal of Taxonomy 2021 2021-10-20 775 86 106 journal article 3948 10.5852/ejt.2021.775.1551 cc10c087-bec3-4947-81d7-b3e5580a5c94 2118-9773 5589689 976D7020-5904-4951-97CE-B4FE58DA12A8 The gilli species group Description BODY ( Fig. 1 ). Medium-sized species, length 8–8.4 mm , humeral width 5.1–5.2 mm . HEAD ( Fig. 2 ). Eyes large, inter-ocular distance seven to nine times width of one eye. Clypeal median emargination broadly u-shaped. Clypeal teeth separated approximately by 1.5 times the basal width of a tooth. Anterior margin of the clypeus, between clypeal teeth, concave and expanded posteriorly into triangular shape. PRONOTUM ( Fig. 3 ). Margin between anterior and medial angle subconcave. Medial angle of pronotum rounded to projected. Punctures almost with the same size, basal punctures only slightly larger than discal punctures. Pronotal disc with shiny points well-defined ( Fig. 3F , arrows), separated between each other and separated or contiguous to punctures; or irregular ( Fig. 3G , arrows), contiguous between to each other and to punctures. ELYTRA ( Fig. 4–5 ). Interstriae with shiny points mixed with the punctures. Interstriae VI and VII with basal carina almost identical in size. Carina of ninth interstria reaching middle of elytral length or slightly surpassing it. Striae I–VIII inconspicuous including apically, only in some parts striae slightly visible and very narrow or striae I–VII conspicuous and narrow, width of third stria 1/30 th or 1/40 th of the distance between stria II and III. If conspicuous, first stria widest and either striae III–VII subequal in width or striae III–VII ill-defined, successively narrower and more ill-defined, with VII almost inconspicuous, and stria VIII conspicuous apical and laterally or only laterally; in both discontinuous in some parts and reaching the apex of carina of the ninth interstria. Apex of elytra with tubercles on interstriae III–VII or III, V–VII ( Fig. 5 ). METAVENTRITE ( Fig. 6 ). With weak posterior excavation, occupying approximately the metaventral basal fourth. Disc with conspicuous punctures at 8 × magnification. Disc punctures at least twice smaller than punctures on anterior-lateral area of metaventral process and dispersed, separated at least by three diameters of a puncture. Punctures on anterior-lateral area of metaventral process separated by less than one diameter. Anterior-medial area of metaventral process with few and smaller punctures than anteriorlateral ones. LEGS. Ventral surface of protibia with a weak carina. Posterior edge of metafemur with two margins, one dorsal and other one ventral. MALE. Protibial spur broad and foliaceus. Mesofemur modified, with slight sinuosity on apical third.Apex of mesotibia wider than female and on ventral-internal margin with a small or large spatulate expansion. Metatrochanter modified or not, if modified with an expansion on distal third. Metafemur with steep tapering on basal third, with expansion on posterior-ventral margin, before that steep tapering. Internal margin of metatibia with small or large tubercles. Ventrite I expanded posteriorly, expansion reaching from the middle of ventrite IV to almost the distal margin of ventrite V; width of expansion on ventrite III variable, narrower to wider than distance between clypeal teeth. Genitalia ( Figs 7–8 ). Paramera subtriangular, with dorsal and ventral edges straight in lateral view. Apex of paramera rounded in dorsal view. Paramera with short and thin apical-dorsal notch ( Fig. 7 , arrows). Medial area of endophallus with one endophallite ( Fig. 8 ). Basal circular shape endophallite with ring very thin and handle strongly broadened medially. FEMALE ( Fig. 9 ). Protibial spur thinner than that of male and spiniform. Apex of mesotibia narrower than that of male. Metatrochanter not modified. Meso- and metafemur not modified. Internal margin of metatibia without tubercles. Metasternal disc with posterior excavation smaller than male. Ventrite V as wide as ventrite VI medially. Ventrite VI narrowed medially. Fig. 1. Habitus of members of the gilli species group. A . Holotype of Deltochilum gilli González- Alvarado & Vaz-de-Mello, 2021, CNCI 379888. B . Holotype of D. jocelynae sp. nov. , CNCI 379889. C . Holotype of D . nonstriatum sp. nov. , CMNEN WSD00041746. D . Holotype of D . quasistriatum sp. nov. , CMNEN WSD00041744. E . Holotype of D . tenuistriatum sp. nov. , CMNEN WSD00041745. Composition Deltochilum gilli González-Alvarado & Vaz-de-Mello, 2021 , D . jocelynae sp. nov. , D . nonstriatum sp. nov. , D . quasistriatum sp. nov. and D . tenuistriatum sp. nov. Fig. 2. Head of members of the gilli species group. A . Holotype of Deltochilum gilli González- Alvarado & Vaz-de-Mello, 2021, CNCI 379888. B . Holotype of D. jocelynae sp. nov. , CNCI 379889. C . Holotype of D . nonstriatum sp. nov. , CMNEN WSD00041746. D . Holotype of D . quasistriatum sp. nov. , CMNEN WSD00041744. E . Holotype of D . tenuistriatum sp. nov. , CMNEN WSD00041745. Remarks This species group is only known from few (eight) specimens and their biology is poorly known. The specimens were collected above 680 m a.s.l. and the highest record is 1411 m a.s.l. ( one specimen does Fig. 3. Pronotum of members of the gilli species group. A . Holotype of Deltochilum gilli González- Alvarado & Vaz-de-Mello, 2021, CNCI 379888. B . Holotype of D. jocelynae sp. nov. , CNCI 379889. C . Holotype of D . nonstriatum sp. nov. , CMNEN WSD00041746. D . Holotype of D . quasistriatum sp. nov. , CMNEN WSD00041744 E . Holotype of D . tenuistriatum sp. nov. , CMNEN WSD00041745. F . Miscrosculpture of pronotal disc, Holotype of D. jocelynae sp. nov. G . Miscrosculpture pronotal disc, Holotype of D . nonstriatum sp. nov. White arrows show the shiny points. Fig. 4. Elytra of members of the gilli species group. A . Holotype of Deltochilum gilli González- Alvarado & Vaz-de-Mello, 2021, CNCI 379888. B . Holotype of D. jocelynae sp. nov. , CNCI 379889. C . Holotype of D . nonstriatum sp. nov. , CMNEN WSD00041746. D . Holotype of D . quasistriatum sp. nov. , CMNEN WSD00041744. E . Holotype of D . tenuistriatum sp. nov. , CMNEN WSD00041745. not have altitude information). They were collected using pitfall traps baited with human dung ( five specimens ), carrion ( one specimen ) as well as via window trap ( one specimen ).