Quedius masasatoi, Smetana, 2007

Brunke, Adam James, 2023, Review of Quedius (Coleoptera, Staphylinidae) described from the 1934 expedition by R. Malaise to Myanmar, European Journal of Taxonomy 864, pp. 117-145 : 132

Masasatoi group

Quedius masasatoi Smetana, 2007 , from China (Fujian, Yunnan), Laos and Vietnam, was previously included in the Apicicornis group of Smetana (2017a), likely out of convenience as it is rather different in habitus. In a similar way, Smetana (2007) placed Q. masatakai Smetana, 2007 , from Laos and Vietnam ( Smetana & Brunke 2021), in the Ripicola group even though it was rather different in habitus. Recently, these two species were shown to be sister groups within ‘Clade E’ of the Microsaurus lineage, and together were sister to a species here described as Malaisdius smetanai gen. et sp. nov. ( Brunke et al. 2021). Quedius masasatoi and Q. masatakai are here included in a newly delineated group, which also includes Q. piceolineatus Scheerpeltz, 1965 from the Malaise material collected in northern Myanmar. A new genus will need to be described for this group but additional morphological study is required in order to provide a more robust diagnosis. The Masasataoi group is provisionally diagnosed within the Microsaurus lineage by the following combination of characters: head with eyes large, clearly longer than temples but temples well-developed ( Fig. 2D ), eyes protruding from lateral head margin, posterior frontal puncture situated at about hind margin of eye, without additional punctures between posterior frontal puncture and basal punctures; antennomeres 6–10 flattened as typical for Quediini , not inflated; pronotum slightly explanate, marginal punctures not removed from marginal bead, anterior angles with marginal bead partly hidden in dorsal view, dorsal row with second and third punctures rather close together (about one puncture diameter or less) and separated from the first by a long gap ( Fig. 5F ), at least on one side; sublateral row not extended posteriad of large lateral puncture, without additional punctures between dorsal and sublateral rows ( Fig. 5F ); scutellum impunctate but sometimes with micropunctures or scratch-like elements, elytra sparsely but evenly punctate, punctures setose ( Fig. 5F ); abdominal tergites III or III–IV with median impunctate area ( Fig. 2D ); mesotarsomeres 2–4 short, triangular.

Figures

Fig. 2. A–E. Dorsal habitus. A. Malaisdius ruficeps (Scheerpeltz, 1965), ♂, paratype (NHW). B. Malaisdius smetanai gen. et. sp. nov., ♂, holotype (NME). C. Quedius (Microsaurus) rutilipennis Scheerpeltz, 1965, ♂, holotype (NHRS). D. Q. (M.) piceolineatus Scheerpeltz, 1965, ♂ holotype (NHRS). E. Q. (M.) impressithorax Scheerpeltz, 1965, ♀ holotype (NHRS). F. Forebody of Q. (M.) impressithorax Scheerpeltz, 1965. Abbreviation: Pf = posterior frontal puncture. Scale bars = 1 mm.

Fig. 5. A. Malaisdius ruficeps (Scheerpeltz, 1965), dorsal abdomen. B. M. smetanai gen. et sp. nov., dorsal abdomen. C–E. Quedius (Microsaurus) rutilipennis Scheerpeltz, 1965. C. Antenna. D. Pronotum (white arrow: marginal punctures removed from marginal bead; black arrow: anterior angles with marginal bead entirely visible in dorsal view). E. Elytra and basal abdomen. F. Q. (M.) masasatoi Smetana, 2007, pronotum (arrows indicating punctures of the dorsal row). Abbreviation: Pf = posterior frontal puncture. Scale bars: A–B, D–E = 1 mm; C, F = 0.5 mm.