Deltochilum gilli Gonzalez-Alvarado & Vaz-de-Mello 2021
Creators: name: González-Alvarado, Arturo
name: Vaz-De-Mello, Fernando Z.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Deltochilum
Deltochilum gilli

description: 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.
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.
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
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).
description: Published as part of González-Alvarado, Arturo & Vaz-De-Mello, Fernando Z., 2021, Taxonomic revision of the Deltohyboma Lane, 1946 gilli species group (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilum), pp. 86-106 in European Journal of Taxonomy 775 on pages 88-93, DOI: 10.5852/ejt.2021.775.1551, http://zenodo.org/record/5589689