Paussus haucki Bednařik & Bocak, 2023

Nagel, Peter, 2024, The Paussus (Scaphipaussus) lanxangensis species group of Indomalayan ant nest beetles (Coleoptera, Carabidae, Paussinae, Paussini) with description of a new species, Zootaxa 5501 (3), pp. 447-457 : 453

Paussus haucki Bednařik & Bocak, 2023 [DP 14 Dec. 2023]

Female holotype specimen only. The original authors classify the species as part of Sg. Scaphipaussus .

Type locality: NE Thailand, Loei prov., Phu Ruea N.P., 17°30’N 101°21’E, 1100 m, 6–9 April 1999, D. Hauck leg. Depository: MBC .

BL 4.2 mm.

Although there is no specimen of either P. wakaharai or P. haucki available to the present study, the original descriptions and illustrations reveal just weak and possibly non-essential differences between the two holotype specimens. Paussus wakaharai and P. haucki were published almost simultaneously with the latter published half a year later.

The original description of P. haucki does not include information on the mouthparts. The description of the pygidium indicates that the marginal semicircular trichome is most probably absent.

According to the original descriptions there seem to be possibly gradual differences between P. wakaharai and P. haucki : Antennal club with posterior excavation absent in P. wakaharai and vertex with large medial tubercle. In P. haucki the antennal club shows a “posterolateral cavity” and vertex “with pair of curved ... vertical shields” ( Bednařik & Bocak 2023, pp. 21, 22). The possible presence of the latter character in P. wakaharai is suggested by the description and illustration ( Maruyama 2023). The probably shrunk antennal club of P. wakaharai , the non-teneral condition of P. haucki and a possible sexual dimorphism (female P. haucki versus male P. wakaharai ) might sufficiently explain the differences. Consequently, P. haucki might turn out to be a younger synonym of P. wakaharai Maruyama & Nakase, 2023 .

Future findings of non-teneral specimens each with the alternative sex will help to clarify the factual situation.