Dichotomius boreus

Chamorro, William, Lopera-Toro, Alejandro & Rossini, Michele, 2021, A new species and distribution records of Dichotomius Hope, 1838 (Coleoptera Scarabaeidae: Scarabaeinae) in Colombia, Zootaxa 4942 (2), pp. 193-206 : 202-203

publication ID	https://doi.org/10.11646/zootaxa.4942.2.3
publication LSID	lsid:zoobank.org:pub:0F533688-AB41-47D1-95A3-AF0B501A9D26
DOI	https://doi.org/10.5281/zenodo.4639256
persistent identifier	https://treatment.plazi.org/id/03A687A0-FD70-E31B-D6F9-69C7FA66FD52
treatment provided by	Plazi (2021-03-12 07:48:21, last updated 2024-11-27 07:24:27)
scientific name	Dichotomius boreus
status

Treatment

Key to species of the Dichotomius boreus View in CoL species group

(Modified from Luederwaldt 1929; Vulcano & Pereira 1967; Sarmiento-Garcés & Amat-García 2014)

1 Pronotum with central lobes conical and directed forward or outward ( Figs. 3 View FIGURE 3 A-E, 4C).............................. 2

- Pronotum with central lobes squared or almost squared, never conical ( Figs. 1 View FIGURE 1 A-C, 2A-B)........................... 5

2 Anterior cephalic carina strongly elevated, with distinct, well-separated tubercles on extremities (width more than 3 mm) ( Figs. 3A, C View FIGURE 3 ).............................................................................................. 3

- Anterior cephalic carina concave (weakly elevated) with small and closer apices (less than 3 mm width) ( Figs. 1D View FIGURE 1 , 2C View FIGURE 2 , 3D View FIGURE 3 , 4C View FIGURE 4 )................................................................................................ 4

3 Anterior cephalic carina with horn-shaped tubercles, curved backward at apex. Frontal transverse carina with a small horn, with rounded apex and located between the eyes ( Fig. 3C View FIGURE 3 )..................... Dichotomius carinatus ( Luederwaldt, 1925) View in CoL

- Anterior cephalic carina with small conical tubercles and rounded apexes. Frontal transverse carina with tubercle with rounded apex located between the eyes ( Figs. 3 View FIGURE 3 A–B).................................. Dichotomius telamon ( Harold, 1869) View in CoL

4 Frontoclypeal carina trituberculate, the central tubercle slightly higher (this character tic may not be easily visible in damaged or minor specimens). Anterior region of pronotum almost vertical above head, superior region with two conical lobes directed forward; lateral declivity of pronotum with a small, acute carina-like protuberance ( Figs. 3 View FIGURE 3 D–-E, 4A–B)..................................................................................... Dichotomius podalirius ( Felsche, 1901) View in CoL

- Frontoclypeal carina trituberculate, central tubercle higher and positioned forward (in major specimens looks like small tubercle). Anterior region of the pronotum almost vertical above the head, superior region with two large conical lobes directed outward; lateral declivity of the pronotum with poorly-developed protuberance ( Fig. 4C View FIGURE 4 )......................................................................................... Dichotomius prietoi Martínez & Martínez, 1982 View in CoL

5 Clypeal carina of male asymmetrical, right portion atrophied. Clypeal carina of female set at mid distance from anterior clypeal edge and tubercle on vertex. Pronotal lobes of large individuals almost subquadrate, apex transversally truncate, strongly emarginate in the male and weakly so in the female ( Figs. 2 View FIGURE 2 A–E)................... Dichotomius boreus ( Olivier, 1789) View in CoL

- Clypeal carina of male symmetrical, lateral tubercles equally developed. Clypeal carina of female closer to anterior clypeal edge than tubercle on vertex. Pronotal lobes of large individuals squared, outer edges normally with a projection rounded at the apex ( Figs. 1 View FIGURE 1 A–F)........................... Dichotomius quadrilobatus Chamorro, Lopera, & Rossini View in CoL , new species

References

Felsche, C. (1901) Beschreibungen coprophage Scarabaeiden. Deutsche Entomologische Zeitschrift, 2, 135 - 155.

Harold, E. (1869 a) Revision des especes qui rentrant dans le genre Pinotus Erichson. L'Abeille, 6, 123 - 144.

Luederwaldt, H. (1925) Novas especies do genero Pinotus (Coleoptera-Lamellicornidae- Coprinae). Boletim do Museu Nacional, Rio de Janeiro, 2 (1), 67 - 69.

Luederwaldt, H. (1929) As especies brasileiras do genero Pinotus, com algumas consideracies tambem sobre outras especies. Revista do Museu Paulista, 16, 1 - 174.

Martinez, A. & Martinez, A. (1982) Una nueva especie de Dichotomius Hope (Col. Scarab. Coprini: Dichotomiina). Anales de la Sociedad Cientifica Argentina, 211 - 212, 3 - 7.

Olivier, G. A. (1789) Entomologie, ou histoire naturelle des insects, avex leurs caracteres generiques et specifiques, leur description, leur synonymie, et leur figure enluminee. Coleopteres. Tome Premier. Baudouin, Paris, France, xx + 433 + xix + 2 pp. https: // doi. org / 10.5962 / bhl. title. 61905

Sarmiento-Garces, R. & Amat-Garcia, G. (2014) Escarabajos del genero Dichotomius Hope, 1838 (Scarabaeidae: Scarabaeinae) en Colombia. Fauna de Colombia Monografia, 4, 1 - 132.

Vulcano, M. A. & Pereira, F. S. (1967) Sinopse dos Passalidae e Scarabaeidae s. str. da regi o Amazonica (Insecta, Coleoptera). Atas do Simposio sobre a Biota Amazonica, Zoologia, 5, 533 - 603.

Figures

FIGURE 1. Dichotomius species. A, Dichotomius quadrilobatus (dorsal view), male; B, Dichotomius quadrilobatus (dorsal view), female; C, Dichotomius quadrilobatus (lateral view), male; D, Dichotomius quadrilobatus, head male; E, Dichotomius quadrilobatus, aedeagus; F, Dichotomius quadrilobatus, endophallites.

FIGURE 2. Dichotomius species. A, Dichotomius boreus, (dorsal view), male; B, Dichotomius boreus, (lateral view), male; C, Dichotomius boreus, head male; D, Dichotomius boreus, aedeagus; E, Dichotomius boreus, endophallites.

FIGURE 3. Dichotomius species. A, Dichotomius telamon (dorsal view), female; B, Dichotomius telamon (lateral view), female; C, Dichotomius carinatus (dorsal view), male; D, Dichotomius podalirius (dorsal view), male; E, (lateral view), male.

FIGURE 4. Dichotomius species. A, Dichotomius podalirius, aedeagus; B, Dichotomius podalirius, endophallites; C, Dichotomius prietoi (dorsal view); D, Dichotomius fortepunctatus (dorsal view).