Pseudesarcus Champion, 1913

Aalbu, Rolf L., Kanda, Kojun, Merkl, Otto, Ivie, Michael A. & Johnston, M. Andrew, 2023, Reconstitution of some tribes and genera of Lagriinae (Coleoptera, Tenebrionidae), ZooKeys 1172, pp. 155-202 : 155

Genus Pseudesarcus Champion, 1913

Figs 61 , 62-66

Pseudesarcus Champion, 1913: 115. Type species: Pseudesarcus villosus Champion, 1913.

Note.

Pseudesarcus is placed incertae sedis within Diaperinae . Pseudesarcus was described in the family Mycetophagidae and transferred to Lagriinae incertae sedis by Lawrence and Newton (1995: 886) ( Bousquet et al. 2018). Pseudesarcus villosus was described from two Panamanian specimens, one of which was photographed by Keita Matsumodo (Fig. 68 ) and the other examined for us by Maxwell Barclay (both from NHMUK). A third specimen from Costa Rica (Figs 70-73 ) was identified as this genus based upon the images and description of the types and was dissected to examine internal structures. We also identified a seemingly undescribed species from Ecuador that possessed internal and external characters used to diagnose Pseudesarcus (Fig. 69 ). Pseudesarcus is clearly a member of Tenebrionidae and part of the ‘tenebrionoid-branch’ (sensu Doyen and Tschinkel 1982; see Matthews and Bouchard 2008).

Pseudesarcus can be characterized by: stellate antennal sensoria present on antennomeres 5-11 (Fig. 69 ); labrum concealed beneath epistoma with symmetrical epistomal tormae; lacinia lacking uncus; procoxal cavities closed internally and externally; mesocoxae closed laterally by mesoventrite and metaventrite; paired defensive glands present, lacking common volume, not pleated (Fig. 70 ); female genital tract with secondary bursa copulatrix, spermatheca forming annulated sclerotized capsule at end of spermathecal gland; ovipositor reduced (Figs 71-73 ).

Based on the above observations, Pseudesarcus is clearly not a lagriine (possesses stellate sensoria, lacks internal ridge of sternite VII) and seems to fall within the circumscription of Diaperinae (see Doyen and Tschinkel 1982; Matthews and Bouchard 2008; Johnston et al. 2020), but lacks any clear relationships with the established tribes (see Johnston et al. 2020). We place it as incertae sedis within Diaperinae until such time as its constituent tribes are better understood.

Figures

Figures 58 - 61. Prosterna of Lagriini. 58 Lagria villosa (Fabricius, 1781) 59 Statira gagatina Melsheimer, 1845 60 Phobelius sp. 61 Rhosaces sp.

Figures 62 - 67. Defensive gland reservoirs of Lagriinae. 62 Lagria villosa (Fabricius, 1781), Lagriini: Lagriina 63 Statira sp., Lagriini: Statirina 64 Phobelius sp., Lagriini: Phobeliina 65 Luprops sp., Lupropini 66 Aediotorix sp., Pycnocerini 67 Cardiothorax sp., Adeliini. Abbreviation: dgr = defensive gland reservoir.

Figures 68 - 73. Dorsal habitus and structures of Pseudesarcus Champion, 1913. 68 Dorsal habitus of Pseudesarcus villosus Champion, 1913, holotype 69 antennae of Pseudesarcus sp. 70 defensive gland reservoirs of P. villosus 71 ovipositor of P. villosus 72 female internal reproductive tract of Pseudesarcus sp. 73 details of spermatheca / spermathecal accessory gland complex of Pseudesarcus sp. Abbreviations: cas = compound antennal sensoria, dgr = defensive gland reservoir, par = paraprocts, goc = gonocoxites, gos = gonostyli, od = oviduct, bc = bursa copulatrix, cs = capsular spermatheca, sag = spermathecal accessory gland. Fig. 68 taken by Keita Matsumoto (NHMUK).