Deltepilissus infernalis ( Harold, 1880 )

Silva, Fernando A. B., Ferreira, Ana B. M. & Génier, François, 2022, Taxonomic revision of the genus Deltepilissus Pereira, 1949 (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilini), Zootaxa 5120 (1), pp. 83-96 : 89-91

Deltepilissus infernalis ( Harold, 1880)

( Figs 2A–L , 3D–F, 3H, 3J, 3L, 3N , 4C–H , 5A–B )

Canthon infernalis Harold, 1880: 150 (original description); Gillet 1911: 30 (catalog); Schmidt 1922: 62, 73 (taxonomic remarks, distribution); Balthasar 1939: 181 (identification key); Blackwelder 1944: 199 (checklist).

Deltepilissus travassosi Pereira, 1949: 231 , 232, fig. 1 (original description); Pereira 1953: 393 (synonymized Deltepilissus travassosi with Canthon infernalis ).

Deltepilissus infernalis: Pereira 1953: 393 (distribution; transferred C. infernalis to the genus Deltepilissus ); Pereira & Martínez 1956: 125 (catalog); Vulcano & Pereira 1964: 660 (catalog); Halffter & Martínez 1977: 66 (checklist); Vaz-de-Mello 2000: 192 (checklist); Krajcik 2006: 47 (checklist); Vaz-de-Mello et al. 2011: 55, fig. 59 (figure); Krajcik 2012: 88 (checklist); Schoolmeesters 2020 (catalog); Vaz-de-Mello 2021 (checklist).

Diagnosis. Deltepilissus infernalis can be distinguished from D. diabolicus by head approximately 1.4 times wider than long ( Fig. 2E ); punctures of central portion of pronotum spaced by at least twice their diameter ( Figs 2A, 2C ); body length 9–11 mm; males with denticle on external edge of protibial spur ( Fig. 2I ), and a conspicuous denticle on inner edge of metatibial spur ( Fig. 2K ); apex of parameres sightly curved inward in dorsal and ventral views ( Figs 3D–E ).

Redescription. Colour and tegument sculpture ( Figs 2A–D ). Body, in general, black. Head and pronotum with light copper or blue sheen. Body surface densely punctate. Length. 9–11 mm. Head ( Fig. 2E ). Densely punctate. Foveiform punctures approximately equally spaced to their diameter; punctures shallower, more spaced and smaller adjacent to clypeal teeth. Clypeus with two widely spaced, small teeth. Surface slightly depressed behind to clypeal teeth. Clypeo-genal suture visible. Thorax. Disc of pronotum with dense foveiform punctures spaced by at least twice their diameter; punctures denser on posterocentral portion ( Figs 2A, 2C ). Hypomera not excavate, with sparse setose punctures on anterior and posterolateral portions ( Fig. 2F ). Hypomera with oblique carina not reaching lateral margin; carina about half hypomeral width. Mesoventrite almost smooth, with sparse punctures. Metaventrite punctures variable in size, smaller and denser medially ( Figs 2B–D ). Elytra ( Fig. 2A, 2C ). Punctures of elytral striae spaced by once or twice their diameter on 1st, 2nd and 3rd striae; punctures more spaced on lateral striae. Elytral striae wider, carinate margins clearly separated. Seventh stria effaced basally. Eighth and ninth striae almost fused, only visible on posterior half. Elytral interstriae with foveiform punctures spaced at least by once or twice their diameter. Pseudepipleural carina complete, visible on entire length of epipleuron. Abdomen ( Fig. 2G ). Punctures denser on lateral surface of ventrites. Pygidium rounded apically, densely punctate, separated from propygidium by carina ( Fig. 2H ). Pygidium with sulcus on basal and apical edges. Legs. Metatibial spur spatulate; apex acutely angular on inner edge ( Fig. 2K ). First meso- and metatarsomeres triangular; tarsomeres 2–4 trapezoidal, the apical subrectangular ( Fig. 2K–L ). Tarsal claws reduced ( Figs 2I–L ). Sexual dimorphism. Females can be distinguished from males by last abdominal ventrite evenly wide ( Fig. 2D ); last abdominal ventrite of males slightly narrower medially ( Fig. 2G ). Females with protibial spur slightly emarginated apically (bifurcate), with a denticle (spiniform process) on inner and external edges ( Fig. 2J ); protibial spur of males with denticle on external edge only ( Fig. 2I ). Females with metatibial spur apically sinuous and bifurcate, inner and external edges with denticles ( Fig. 2L ); males only with a conspicuous denticle on apical inner edge of metatibial spur ( Fig. 2K ). Apical third of metatibiae almost straight in females ( Fig. 2L ), distinctly curved inward in males ( Fig. 2K ). Aedeagus. Parameres symmetrical, subparallel in lateral view, abruptly pointing downward apically ( Fig. 3F ). Apex of parameres curved inward in dorsal and ventral views ( Figs 3D–E ). Endophallus. Lamella copulatrix absent. Superior right peripheral endophallite ring shaped; lateral projection arched, rounded apically ( Fig. 3H ). Frontolateral peripheral endophallite elongate, irregular ( Fig. 3J ). Complex of axial and subaxial endophallites elongate, irregular ( Fig. 3N ). Additional endophallites short, comma shaped ( Fig. 3L ).

Type material. Canthon infernalis Harold. Lectotype ♂ (here designated; MFNB)( Figs4 C-D):“ HOLOTYPE // Brasil Besuxe // 9005 // Type // infernalis / Har // SYNTYPUS / Canthon / infernalis Harold, 1880 / labelled by MNHUB 2013. Deltepilissus travassosi Pereira. Holotype ♂ ( MZSP) ( Figs 4E–H ): Rio de Janeiro, Paineiras, IV-1934, Dr. L. Travassos.

Additional material. BRAZIL: no specific locality [Brasil – inter], no date and collector, – 1 unsexed specimen ( BMNH) . ESPÍRITO SANTO, Mimoso do Sul , 05.IX.1986, R.L.C. Baptista – 1 ♀ ( CEMT) . RIO DE JANEIRO, no date and collector – 1 unsexed specimen ( BMNH – ex Fry collection); Itaguaí, Serra da Caveira , 800 m, 25.II.1948, W. Zikán – 1 unsexed specimen ( MNRJ) ; Itaguaí, Serra da Caveira , 600 m, 25.II.1948, W. Zikán – 1 ♀ ( CEMT) ; Nova Friburgo , XII.1999, E. & P. Grossi – 1 ♀ ( CEMT) ; Nova Friburgo , XII.1999, E. & P. Grossi – 1 unsexed specimen ( CERPE) ; Rio de Janeiro, Jacarepaguá, 1956, no collector – 1 ♂ ( CMNC ‒ ex. H. & A. Howden collection, ex. A. Martínez collection). SÃO PAULO, Guarujá, Forte dos Andradas, XII.1971, Ayr Bello – 1 ♂ ( AMBC) .

Habitat. This species inhabits the Brazilian Atlantic rainforest from southern Espírito Santo to São Paulo states, mainly at low elevation along the coastal parts of the Atlantic rainforest, from 0– 800 m. A single specimen was collected by Renner Baptista in a soil block (manure and roots) dug up in a cattle ranch in Espírito Santo, Brazil. A specimen was also collected within debris (leaves, seaweed, broken shells, insects and some plastic garbage) deposited on beach sand in Guarujá, São Paulo, Brazil (Ayr Bello, personal communication). All those records were made from manual collect method. However, the data presented above are not enough to define the food habits of D. infernalis . As already mentioned for D. diabolicus , the baits traditionally used for collecting dung beetles did not attract D. infernalis .

Distribution. Known from southeastern Brazil (Espírito Santo, Rio de Janeiro and São Paulo). Literature records. BRAZIL: RIO DE JANEIRO, Itaguaí ( Pereira 1953), Rio de Janeiro [Paineiras] ( Pereira 1949, 1953), Rio de Janeiro [cited as “Guanabara”, the state-level name by which the city was known between 1960 and 1975] ( Vulcano & Pereira 1964) ( Fig. 5 ).

Remarks. Harold (1880) described Canthon infernalis from one or more specimens collected by von Olfers, a German naturalist, in Brazil. A type specimen was found and photographed by Fernando Vaz-de-Mello in MFNB (see material and methods section). Pereira (1949) described Deltepilissus travassosi on a specimen from Rio de Janeiro, Brazil [holotype from Parque Nacional da Tijuca, Paineiras, Rio de Janeiro, Brazil; housed in MZSP]. Later, Pereira (1953) considered D. travassosi a junior subjective synonym of Canthon infernalis and transferred the latter to the genus Deltepilissus . In this study, we examined the holotype of D. travassosi and compared it with the photographs of the type of Canthon infernalis , and we did not find significant differences in their external morphology. Unfortunately, we could not examine the genitalia of the holotype of D. travassosi , as the current policies of the MZSP do not allow the dissection of name-bearing type specimens (i.e., holotypes, lectotypes) if there are no other available types in that collection (i.e., paratypes, paralectotypes). However, because D. travassosi Pereira was synonymized with Canthon infernalis Harold by its author ( Pereira 1953), we agree with Pereira (1953) to consider D. travassosi as synonym of D infernalis .

Conservation status. Over the past 25 years, the several collecting events in Atlantic rainforest remnants yielded only two specimens of D. infernalis (see “additional material”). Other known records for this species are older, with specimens collected between the early 19 th century (1818‒1819 by von Olfers, see Papavero 1971) and the 1980s.

The extent of occurrence of this species was estimated as up to 100 km 2, with large surrounding areas of unsuitable habitat in southeastern Brazil. According to the International Union for Conservation of Nature (2012) criteria, D. infernalis may be assessed as Critically Endangered (CR) under criterion B1ab(iii)+B2ab(iii), mainly due to high fragmentation and destruction of the Atlantic rainforest and low number of specimens collected over more than 140 years since its description.

Figures

FIGURE 2. Details of the external morphology of Deltepilissus infernalis. A–B, Body, male, dorsal and ventral views, respectively; C–D, body, female, dorsal and ventral views, respectively; E, head, male; F, hypomeron, male; G, abdominal ventrites, male; H, pygidium, male; I–J, detail of protibial spur, male and female, respectively; K–L, right metatibia, ventral view, male and female, respectively (arrows indicate apex of metatibial spur).

FIGURE 3. Details of the male genitalia in Deltepilissus. A–C, Deltepilissus diabolicus: A, parameres, dorsal view; B, parameres, ventral view; C, aedeagus, lateral view. D–F. Deltepilissus infernalis: D, parameres, dorsal view; E, parameres, ventral view; F, aedeagus, lateral view. G, Deltepilissus diabolicus superior right peripheral (SRP) endophallite. H, Deltepilissus infernalis superior right peripheral (SRP) endophallite. I, Deltepilissus diabolicus frontolateral peripheral (FLP) endophallite. J, Deltepilissus infernalis frontolateral peripheral (FLP) endophallite. K, Deltepilissus diabolicus additional endophallites (AE). L, Deltepilissus infernalis additional endophallites (AE). M, Deltepilissus diabolicus complex of axial and subaxial (A+SA) endophallites. N, Deltepilissus infernalis complex of axial and subaxial (A+SA) endophallites.

FIGURE 4. Type specimens in Deltepilissus and respective label data. A–B, Lectotype of Canthon diabolicus Harold, 1880: A, body, dorsal view; B, labels. C–D, Lectotype of Canthon infernalis Harold, 1880: C, body, dorsal view; D, labels. E–H, holotype of Deltepilissus travassosi Pereira, 1949: E, body, dorsal view; F, head; G, left protibia, dorsal view; H, protibial and tarsal claws. Photographs A–D provided by Fernando Z. Vaz-de-Mello.

FIGURE 5. Known distribution of species of Deltepilissus. A, Records plotted on terrestrial biomes layer; B, records plotted on elevational range layer.