Discodon obscurior Pic, 1906

Biffi, Gabriel & Geiser, Michael, 2022, A revision of Discodon tricolor (Guérin-Méneville) and its mimics from the Atlantic forests of Brazil (Coleoptera: Cantharidae), European Journal of Taxonomy 834 (1), pp. 148-189 : 159-161

publication ID	https://doi.org/10.5852/ejt.2022.834.1907
publication LSID	lsid:zoobank.org:pub:C2DF7AC2-3D99-43FF-BB36-CEF8E8747160
DOI	https://doi.org/10.5281/zenodo.7020058
persistent identifier	https://treatment.plazi.org/id/03CEA025-FFEC-FFBF-FDA9-FEEE2C7AFFC9
treatment provided by	Felipe (2022-08-23 20:58:01, last updated 2024-11-29 12:47:14)
scientific name	Discodon obscurior Pic, 1906
status	stat. nov.

Treatment

Discodon obscurior Pic, 1906 stat. nov.

Figs 5A–C View Fig , 6D, O View Fig , 7D View Fig , 8D View Fig , 9D View Fig , 10D View Fig , 11J–L View Fig , 15D View Fig

Discodon albonotatum var. obscurior Pic, 1906: 90 .

Discodon albonotatum var. obscurior – Delkeskamp 1939: 155 (catalogue); 1977: 259 (catalogue). — Blackwelder 1945: 364 (checklist).

Diagnosis

Similar to D. nigrocephalum by general coloration ( Fig. 5A–B View Fig ). It differs especially by the elytra being smoother ( Fig. 5A View Fig ), the pronotum ( Figs 7D View Fig , 8D View Fig ) with anterior and lateral margins broadly arched, the shape of the lobe of the tarsal claws ( Fig. 9D View Fig ), the ventrite VII of males ( Fig. 10D View Fig ) and females ( Fig. 15D View Fig ) and the aedeagus ( Fig. 11J–L View Fig ). The colour of the antennae ( Fig. 5A–B View Fig ) of D. obscurior is usually light brown to orangish.

Type material

Lectotype (here designated) BRAZIL • ♀; Rio de Janeiro, Nova Friburgo ; Feb.–Mar. 1903; E. Gounelle leg.; “Muséum Paris, Coll. M. Pic ”; MNHN, Paris EC13554 ( Fig. 5A–C View Fig ).

Paralectotype BRAZIL • 1 ♀; same collection data as for lectotype; MNHN, Paris EC13555 .

Other material examined (38 specimens)

BRAZIL • 28 ♂♂, 10 ♀♀; Rio de Janeiro, Petrópolis ; 5–7 Mar. 1962; J. Bechyné leg.; MZSP 46398 to 46435 .

Re-description

Body length: 11.0–13.0 mm. Coloration ( Fig. 5A–B View Fig ): head pitch black, lustrous, except in lateral corners of clypeus, dark brown; mandibles dark brown, darker at base and tip; maxillary and labial palpi dark brown, light brown in last palpomeres; antennomere I black, the latter light brown, sometimes orangish. Pronotum ( Figs 7D View Fig , 8D View Fig ) lustrous, partly translucent, with broad irregular black band from anterior to posterior margin, black band usually with lateral projections in posterior third; background pale yellow with diffuse orange regions. Scutellum and elytra entirely pitch black, slightly lustrous. Thorax, legs and abdomen black, tarsal claws brown.

Male ( Fig. 5A–B View Fig )

Head short, slightly wider than long, excluding eyes; integument smooth, densely covered with short and fine yellow setae; frons short, vertex flat, occipital region convex, broadly rounded behind eyes. Clypeus flat, anterior margin emarginate, slightly projected anteriorly with median incision. Eyes large, rounded, slightly prominent. Mandibles falciform, acute, without accessory teeth. Last maxillary and labial palpomeres securiform. Antennae ( Fig. 6D View Fig ) long, slightly flattened dorsoventrally; antennomeres III–X narrowing proximally, sub-serrate; antennomeres without longitudinal lines. Pronotum ( Fig. 7D View Fig ) wide, 1.5 times as wide as long; anterior margin, anterior angles and lateral margins broadly arched; lateral margins with shallow notch at posterior third; integument smooth, densely covered with very fine yellow setae. Elytra long, each elytron 4.2 times as long as wide, wider medially; integument coriaceous, densely covered with short and fine decumbent setae, and much longer thick erect setae. Legs slender, densely pubescent, covered with long and thick setae; tarsi flattened dorsoventrally, fourth tarsomere with transversal slit at base; anterior prothoracic tarsal claws ( Fig. 9D View Fig ) broadly lobed basally, lobe with sinuous to truncate margin; posterior claws on meso- and metathoracic tarsal claws apparently split at apex, with fine protruding tooth slightly shorter than claws. Abdomen weakly sclerotised, coriaceous, densely covered with long setae; ventrite VI notched at posterior margin; ventrite VII ( Fig. 10D View Fig ) with concave lobes, inner margins divergent, directed ventrally, with sharp borders; outer margins straight, apical margins truncate, meeting medially. Aedeagus ( Fig. 11J–L View Fig ): ventral wall of tegmen short, lateral margins convergent from apical half; apex forming a pair of rounded lobes and salient border projecting ventrally; fringe of long setae along lateral margins of tegmen dorsally; parameres very long, robust, falciform, projecting dorsally, apex rounded with small acute tip; median lobe membranous, with very long and broad flattened central sclerite dorsally.

Female

Similar to male; antenna ( Fig. 6O View Fig ) longer; pronotum ( Fig. 8D View Fig ) more transverse, wider, 1.6 times as wide as long, sub-rectangular, anterior margin nearly straight, lateral margins without notch; tarsal claws without basal lobe or apical slit; ventrite VI not notched, distal margin slightly arched, concave; ventrite VII ( Fig. 15D View Fig ) broad, lateral and distal margins sinuous, apex without strong projections, with shallow lobes not strongly projecting posteriorly.

Distribution

Brazil (Rio de Janeiro state) ( Fig. 16 View Fig ).

References

Blackwelder R. E. 1945. Checklist of the coleopterous insects of Mexico, Central America, the West Indies and South America, pt. 3. Bulletin of the United States National Museum 185: 345 - 550. https: // doi. org / 10.5479 / si. 03629236.185.3

Delkeskamp K. 1939. Col. Cantharidae. Coleopterorum Catalogus Pars 165. Dr W. Junk, ' s-Gravenhage.

Pic M. 1906. Noms nouveaux et diagnoses de Cantharini (Telephorides) europeens et exotiques. L'Echange, Revue Linneenne 22: 89 - 92. Available from https: // www. biodiversitylibrary. org / item / 285236 # page / 99 / mode / 1 up [accessed 15 Aug. 2022].

Pic M. 1930. Malacodermes exotiques (suite). L'Echange, Revue Linneenne 46 (440, hors-texte): 81 - 85.

Wittmer W. 1952. 13. Beitrag zur Kenntnis der neotropischen Malacodermata (Coleoptera). Revista Chilena de Entomologia 2: 197 - 205.

Figures

Fig. 5. Primary types, habitus and labels. A–C. Discodon albonotatum obscurior Pic, 1906 (lectotype, ♀, MNHN EC13554), dorsal habitus, ventral view and labels. D. Discodon tenuecostatum sp. nov. (holotype, ♂, MZSP 46459). E–G. Discodon nigrocephalum Pic, 1949 (lectotype, ♂, MNHN EC13556), dorsal habitus, ventral view and labels. Photographs A–C and E–G by Christophe Rivier (MNHN, Paris). Scale bars = 5.0 mm.

Fig. 6. Right antennae, dorsal view. A–K. Males. L–U. Females. A, L. Discodon tricolor (Guérin- Méneville, 1832). B, M. Discodon neoteutonum sp. nov. C, N. Discodon vanini sp. nov. D, O. Discodon obscurior Pic, 1906 stat. nov. E, P. Discodon lineaticorne sp. nov. F, Q. Discodon aurimaculatum sp. nov. G, R. Discodon marginicolle sp. nov. H, S. Discodon tenuecostatum sp. nov. I, T. Discodon tamoio sp. nov. J, U. Discodon viridimontanum sp. nov. K. Discodon crassipes Wittmer, 1952. Scale bars = 1.0 mm.

Fig. 7. Pronotum of males, dorsal view. A. Discodon tricolor (Guérin-Méneville, 1832). B. Discodon neoteutonum sp. nov.C. Discodon vaninisp. nov. D. Discodon obscurior Pic, 1906 stat. nov. E. Discodon lineaticorne sp. nov.F. Discodon aurimaculatumsp. nov. G. Discodon marginicolle sp. nov.H. Discodon tenuecostatum sp. nov. I. Discodon tamoio sp. nov. J. Discodon viridimontanum sp. nov. K. Discodon crassipes Wittmer, 1952. Scale bar = 1.0 mm.

Fig. 8. Pronotum of females, dorsal view. A. Discodon tricolor (Guérin-Méneville, 1832). B. Discodon neoteutonum sp. nov.C. Discodon vaninisp. nov. D. Discodon obscurior Pic, 1906 stat. nov. E. Discodon lineaticorne sp. nov.F. Discodon aurimaculatumsp. nov. G. Discodon marginicolle sp. nov.H. Discodon tenuecostatum sp. nov. I. Discodon tamoio sp. nov. J. Discodon viridimontanum sp. nov. K. Discodon testaceipes Pic, 1930 stat. nov. Scale bar = 1.0 mm.

Fig. 9. Tarsal claws and leg of males. A–K. Anterior claw of fore tarsus, lateral view. A. Discodon tricolor (Guérin-Méneville, 1832). B. Discodon neoteutonum sp. nov. C. Discodon vanini sp. nov. D. Discodon obscurior Pic, 1906 stat. nov. E. Discodon lineaticornesp. nov. F. Discodon aurimaculatum sp. nov. G. Discodon marginicolle sp. nov. H. Discodon tenuecostatum sp. nov. I. Discodon tamoio sp. nov. J. Discodon viridimontanum sp. nov. K. Discodon crassipes Wittmer, 1952. L. Hind leg of male Discodon crassipes Wittmer, 1952, ventral view. Black arrows show the lobe of the anterior tarsal claw of the protarsi. Scale bars: A–K = 0.5 mm; L = 1.0 mm.

Fig. 10. Ventrite VII of males. A. Discodon tricolor (Guérin-Méneville, 1832). B. Discodon neoteutonum sp. nov. C. Discodon vanini sp. nov. D. Discodon obscurior Pic, 1906 stat. nov. E. Discodon lineaticorne sp. nov. F. Discodon aurimaculatum sp. nov. G. Discodon marginicolle sp. nov. H. Discodon tenuecostatum sp. nov. I. Discodon tamoio sp. nov. J. Discodon viridimontanum sp. nov. K. Discodon crassipes Wittmer, 1952. Scale bar = 1 mm.

Fig. 11. Aedeagus, dorsal, ventral and lateral views. A–C. Discodon tricolor (Guérin-Méneville, 1832). D–F. Discodon neoteutonum sp. nov. G–I. Discodon vanini sp. nov. J–L. Discodon obscurior Pic, 1906 stat. nov. Scale bar = 1 mm.

Fig. 15. Ventrite VII of females. A. Discodon tricolor (Guérin-Méneville, 1832). B. Discodon neoteutonum sp. nov.C. Discodon vaninisp. nov. D. Discodon obscurior Pic, 1906 stat. nov. E. Discodon lineaticorne sp. nov.F. Discodon aurimaculatumsp. nov. G. Discodon marginicolle sp. nov.H. Discodon tenuecostatum sp. nov. I. Discodon tamoio sp. nov. J. Discodon viridimontanum sp. nov. K. Discodon testaceipes Pic, 1930 stat. nov. Scale bar = 1 mm.