Trogellus (Trogoides) trajectus Paulsen, 2018

Paulsen, M. J., 2018, Generic changes in the stag beetle tribe Aesalini (Coleoptera: Lucanidae: Aesalinae) with the description of two new species, Insecta Mundi 666, pp. 1-10 : 7-9

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Trogellus (Trogoides) trajectus Paulsen

new species

Trogellus (Trogoides) trajectus Paulsen , new species

Type material. Holotype male, KSEM, labeled: a) “ PANAMA: Darién / Cana Biological Station / Serranía de Pirre , 1200 m / 7°45′18″N, 77°41′6″W / 04–07 Jun 1996; J. Ashe, / R. Brooks, PAN1AB96 105 / ex: flight intercept trap ”; b) database label “SM0043836 / KUNHM–ENT”; c) on red paper, “ Trogellus / trajectus Paulsen ♂ / HOLOTYPE ” GoogleMaps . Allotype female, KSEM, labeled: a) “ PANAMA: Darién / Cana Biological Station / Serranía de Pirre , 1200–1400 m / 7°45′18″N, 77°41′6″W / 05 Jun 1996; J. Ashe, / R. Brooks, PAN1AB96 043 / ex: fungusy log”; b) database label “SM0039755 / KUNHM–ENT”; c) on red paper, “ Trogellus / trajectus Paulsen ♀ / ALLOTYPE ” GoogleMaps . Paratype female, MJPC, labeled: a) as holotype; b) database label “SM0043845 / KUNHM–ENT”; c) on yellow paper, “ Trogellus / trajectus Paulsen ♀ / PARATYPE ” .

Description. Holotype male ( Fig. 8 View Figures 8–9 ). Length: 4.5 mm. Width: 2.4 mm. Color: Everywhere dark reddish brown. Vestiture: Dorsally scales consisting of two types: erect bristles and brownish gray tomentosity (obscuring color of integument). Head: Canthus long (reaching pronotum when head retracted) and broad. Eye dorsally narrowed. Clypeus triangular, apex not distinctly produced. Mentum bifoveate. Mandibles weakly dentate externally at basal angulation. Pronotum: Surface densely punctate, some punctures with erect bristles (lacking distinct tubercle), remaining punctures obscured by tomentous scales. Metasternum: Punctures anterolaterally large in size. Elytra: Surface everywhere with moderate punctures obscured by tomentous scales, and with rows of moderate punctures with blunt bristles and a shiny tubercle anteriorly; bristles moderately long (2X longer than 4 th metatarsomere). Legs: Protibiae tridentate, teeth subtriangular; margin between teeth more concave than in other species. Mesotibia with 2 larger external teeth, 1-2 smaller teeth, and acute apex. Metatibia straight, with 1–2 small median teeth and 1–2 smaller teeth proximally; apex acute. Male genitalia: Parameres narrow and elongate, 1/2 as long as median lobe, appressed to median lobe; median lobe symmetrical, with moderate, rounded lateral processes at distal third ( Fig. 8d View Figures 8–9 ).

Description. Allotype female, paratype female, differing from the holotype in the following. Length: 4.5–4.6 mm. Width: 2.5–2.6 mm. Legs: Metatibia with external teeth almost obsolete, apex tumid. Female genitalia: Not examined.

Remarks. This species is a member of the subgenus Trogoides Paulsen based on the lateral projections on the median lobe of the male genitalia. Uniquely in this species the lobes are rounded, not triangular ( Fig. 8d View Figures 8–9 ). The external protibial teeth are more triangular in this species making the external margin more concave between them, while a flat margin had been a uniting character for the rest of the species in the subgenus. This is a matter of degree, and species in other subgenera possess a distinctly concave margin. Interestingly, the dorsal bristles of T. trajectus are occasionally blunt, but for the most part distinctly acute, which removes blunt bristles as a useful character for delineating the subgenus.

Etymology. The name is a Latin adjective in the nominative singular referring to “crossing over, a passage”, a reference to the species’ location in the Darién Gap and its potential to also occur in South America.

Distribution. PANAMA: Darién: Cana Biological Station. The type locality is less than 7 km from Colombia, so this species is likely to occur in that country. When discovered it is expected to qualify the genus as a member of the South American fauna.