Deltochilum (Aganhyboma) trisignatum Harold 1881
Creators: name: Silva, Fernando A. B.
name: Louzada, Júlio
name: Vaz-De-Mello, Fernando
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Deltochilum
Deltochilum trisignatum

description: Deltochilum (Aganhyboma) trisignatum Harold 1881
(Figs 9, 27, 35, 44, 52, 66, 69, 89, 95)
Deltochilum trisignatum Harold 1881 [1880]: 150 (original description) Heyne 1900: 61 (description)
Gillet 1911: 36 (catalogue)
Pessôa & Lane 1941: 428, 431 and 432 (description and identification key) Blackwelder 1944: 203 (checklist)
Deltochilum (Aganhyboma) trisignatum Kolbe 1893: 192 Shipp 1897: 195
Paulian 1938: 240, 252, 253, 256, Figs 2, 18, map No 2 (description, taxonomic comments and identification key) Lane 1946: 173, 174 (taxonomic comments)
Pereira & Martínez 1956: 121
Vulcano & Pereira 1964: 642 (catalogue)
Vaz-de-Mello 2000: 192 (checklist)
Description. Body. Head black with violet hue, pronotum yellowish brown with black spots, elytra reddish brown (Fig. 95). Ventral surface black with green reflections. Length 17 to 19 mm. Head. Dorsal surface completely covered by closely spaced to confluent foveiform punctures resulting in rugosity, anterior punctures smaller than those at center. Punctures margin well-defined (impressed). Margin between clypeal teeth and genae curved outward near clypeogenal suture. Thorax. Surface of pronotum with deep and dense foveiform punctures forming rugosity. Anteromedial punctures much smaller than posteromedial punctures. Margin of pronotum (close to lateral angles), curved inward, lacking emargination. Anterior margin with three black spots, one covering each angle and one at center. Pronotum with small black spot close to lateral angles and dark spot in posterior part of disc. Margin between lateral and posterior angles distinctly convex (curved outward). Elytra. Striae weakly marked, with almost inconspicuous punctures. Lateral margins evenly curved outward (Fig. 95). Interstrial surface with weak, medium-size foveiform punctures intermingled with dense microtubercles, some of which are confluent, shining and forming a glossy zone. First interstria brighter than rest of elytra. Basal carina of seventh interstria weak and short (Fig. 95), approximately the same length as metatibial spur. Length of apical carina of seventh interstria 1.5 times that of apex of sixth interstria. Abdomen. Punctures large and conspicuous, concentrated on anterior and posterior margins of sternites and reduced to a narrow belt along midline of abdomen. Pygidium almost completely covered by nearly confluent, large, foveiform punctures, leaving only a short, smooth medial line from base to about midlength of pygidial surface. Apex of pygidium rounded. Legs. Protibia sharply widened along inner margin from basal third to apex (Fig. 66). Middle protibial tooth closer to apical tooth than to basal tooth (Fig. 66). Apical third of metatibia strongly curved inward (Fig. 67). Inner margin of metatibia with a longitudinal row of small tubercles. Apex of metatibia with six clearly visible longitudinal carinae. Anterior margin of profemur effaced at middle portion (Fig. 69). Most foveiform punctures of the profemur elliptical. Metatarsus approximately one-third as long as metatibia. Secondary sexual characters. Male abdomen slightly more longitudinally flattened than that of female. Apical margin of pygidium more dilated in male. Male protibial spur rounded at apex. Female spur acuminate apically.
Material studied. Lectotype (MNHU) [here designated] ♂: 1. [old white label, handwritten]. 8915; 2. [green label, handwritten]. trisignatum Harold Brasilia; 3. [red label, bordered and printed in black, handwritten]. Lectotype Deltochilum trisignatum Harold des. F.Z. Vaz-de-Mello, 2014. Paralectotypes (MNHU) 2 ♀♀: ♀ 1. [old white label, handwritten]. 8915; 2. [green label, handwritten]. Brasilia; 3. [yellow label, bordered and printed in black, handwritten]. Paralectotype Deltochilum trisignatum Harold des. F.Z. Vaz-de-Mello, 2014./ ♀ 1. [old white label, handwritten]. 8915; 2. [yellow label, bordered and printed in black, handwritten]. Paralectotype Deltochilum trisignatum Harold des. F.Z. Vaz-de-Mello, 2014.
Taxonomic notes. A lectotype is here designated in order to maintain nomenclatural stability by choosing the only male (presenting characters that are easier to use for distinguishing from other species) among the available syntypes as the single name-bearing type.
Non-type material [30]: ARGENTINA: TUCUMAN [probably mislabelled] (1 ♀ MNHN); BRAZIL: BAHIA: Santa Teresinha, Pedra Branca, (12°51.33'S, 39°28.575'W), 2.II.2009, L.R.M. Oliveira (3 MZUEFS); ESPÍRITO SANTO: P. Cachoeira, (2 ♀ MZUSP); Conceição da Barra, 22–28.X.1968, C. & C.T. Elias (1 ♀ DZUP); Linhares, II.1964 (1 ♂ DZUP); same, XII.1967 (1 ♀ DZUP); Linhares, Lagoa do Macuco, (19°03'50"S, 39°58'43"W), 26–27.I.2000, F. Génier & S. Ide (1 ♂ 3 ♀ CEMT, 2 ♀ CMN); Linhares, Povoação, (19°36'S, 39°48'W), 3.XII.2000, G. Schiffler (1♂ CEMT); MINAS GERAIS: Mar de Hespanha, 9.XII.1910, J.F. Zikán (1 ♀ CEMT, 1 ♂ MZUSP); Marliéria, Parque Estadual do Rio Doce, (19°42'09.22"S, 40°30'54.21"W), 11.I.2005, S.S.P. Almeida & M.R. Pereira (10 ♂ 1 ♀ CEMT); RIO DE JANEIRO: Sto. Antonio dos Brotos, Districto de San Fidelis, 1876–1882, Auguste Vincent de Lyon (1 ♂ MNHN).
Sampling methods. Millipede carrion baited pitfall trap [3 specimens]; Flight interception trap [1]; un-baited pitfall trap [11]. The un-baited pitfall traps contained formalin solution (as a preservative) may act as an attractant for beetles predacious on millipedes, since millipedes often release defence secretions containing formaldehydebased compounds.
Habitat. Brazil (southern Bahia, Espirito Santo and Minas Gerais) (Fig. 89), from available data this species inhabits lowland Atlantic forest, with sandy soil. A single specimen was collected from “cabruca” vegetation (agricultural area where the cacao is planted in the midst of the natural vegetation of Atlantic forest). The known elevation range is 10 to 130 m AMSL.
Diagnosis and remarks (within the trisignatum complex): head black with violet hue, pronotum yellowishbrown with three distinct black spots, elytra reddishbrown; dorsal surface of head completely covered by closely spaced to confluent foveiform punctures resulting in rugosity; margin of pronotum (close to lateral angles) curved inward. The following aedeagus characters are also diagnostic: parameres shorter than phallobase, rounded at apex, in lateral view forming an angle of approximately 30° with phallobase (Fig. 9). Lamella copulatrix: right lobe "scaphopode" shaped (Fig. 35). Superior right peripheral sclerite (SRP) as in Fig. 44. Fronto-lateral peripheral sclerite (FLP) as in Fig. 52. Center of genital segment with a well-sclerotized portion and "M"-shaped (Fig. 27). There is some variation in the pronotum of four specimens examined, which display yellow coloration. The dark spot on posterior portion of pronotal disc can be difficult to see in some individuals.
description: Published as part of Silva, Fernando A. B., Louzada, Júlio & Vaz-De-Mello, Fernando, 2015, A revision of the Deltochilum subgenus Aganhyboma Kolbe, 1893 (Coleoptera: Scarabaeidae: Scarabaeinae), pp. 451-504 in Zootaxa 3925 (4) on pages 462-463, DOI: 10.11646/zootaxa.3925.4.1, http://zenodo.org/record/244795