Afroquedius, Solodovnikov, 2006

Brunke, Adam James, Żyła, Dagmara, Yamamoto, Shûhei & Solodovnikov, Alexey, 2019, Baltic amber Staphylinini (Coleoptera: Staphylinidae: Staphylininae): a rove beetle fauna on the eve of our modern climate, Zoological Journal of the Linnean Society 187, pp. 166-197 : 180

Afroquedius and Valdiviodes Smetana.

Diagnosis

The two genera of Afroquediina are dissimilar in habitus and body sculpture but can be recognized easily among all other Staphylinini by the combination of a deeply and broadly bilobed labrum ( Fig. 2A), lack of frontoclypeal setae ( Fig. 2A) and elytral subbasal ridge extending horizontally to the humerus ( Fig. 2B). The following characters are unique to Afroquediina : the broad, shield-shaped prosternum with short lateral arms and the broad, well-sclerotized strip on the dorsal side of the internal sac of the aedeagus. The frontoclypeal setae are also missing in Devilleferus Jenkins Shaw & Solodovnikov ( Jenkins Shaw et al., 2017) , but this genus otherwise lacks all above character states of Afroquediina . The broadly bilobed labrum occurs in the distantly related Staphylinini Propria clade, especially in Xanthopygina , where it is obvious that it has evolved convergently. All other incertae sedis genera in Staphylinini not included in the present phylogenetic analysis [ Beeria Hatch , Strouhalium Scheerpeltz , Descarpentriesiellus Jarrige and the members of the Quediomacrus group ( Brunke & Solodovnikov, 2013)] do not share the character states of Afroquediina and belong to the Northern Hemisphere clade based on the presence of a scutellar collar. Furthermore, Beeria and the Quediomacrus group have been included previously in phylogenetic analyses ( Brunke & Solodovnikov, 2013; Jenkins Shaw et al., 2017) and were phylogenetically distant from Afroquediina and Antimerina . The basal elytral ridge is secondarily extended horizontally to the humerus in the enigmatic Madagascan genus Descarpentriesiellus , but this genus differs from Afroquediina in a number of character states. It might be related to subtribes Erichsoniina and Acylophorina based on the inflated apical antennomere and the elongate metatarsomeres ( Schillhammer & Brunke, 2018).

Description

Medium-sized (7.5–12.6 mm), moderately robust rove beetles, ranging from dark and strongly glossy, to iridescent greenish-coppery. Dorsal forebody either entirely lacking microsculpture or with unique patchwork of microsculptured fragments, whirled in differing directions ( Fig. 2A), neither matching the concentric, transverse waves common in Staphylinini . Antennae non-geniculate; antennomeres 1–4 lacking tomentose pubescence; antennomeres 1–3 lacking dense setae, and apical antennomere lacking broad microsetal field. Head without frontoclypeal puncture ( Fig. 2A), single basal puncture present, dorsal basal ridge absent, labrum widely divided to base by broad, U-shaped notch into two lobes ( Fig. 2A), with gular sutures strongly converging toward base of head and either fusing ( Afroquedius ) or closely spaced ( Valdiviodes ). Labial palpi without dense brushes on second segment. Mandibles curved, with single tooth in basal half. Prothorax with membranous postcoxal process, distinctly interrupted at base by inferior line; basisternum shield-shaped, lateral arms very short; basisternum with pair of macrosetae; pronotum and prosternum not fused in procoxal cavity. Mesoscutellum either punctate ( Afroquedius ) or impunctate ( Valdiviodes ); posterior scutellar ridge present; subbasal elytral ridge not forming scutellar collar, extending to humerus; humerus with row of spines ( Fig. 2B). Elytral epipleuron without row of setae in impressed punctures. Profemur without apical row of lateroventral spines; protarsomeres trapezoid and flattened, with tenent setae ventrally. Meso- and metatarsomeres trapezoid and flattened, setose on disc. Metatarsus lacking tenent setae. Metacoxae without transverse carina. All tarsi with five segments and pair of empodial setae; setae not distinctly longer on mid- and hindleg compared with foreleg. Wings with veins CuA and MP4 completely separate; MP3 present (wing veins not codable in Valdiviodes owing to strong brachyptery). Protergal glands each present as well-developed acetabulum. Abdominal tergites without accessory basal lines; anterior transverse basal lines not curved to encompass spiracles entirely, without true posterior transverse basal lines. Abdominal sternite III with basal transverse carina either obtuse ( Valdiviodes ) or sharply produced ( Afroquedius ).

Male: Sternite VIII with distinct emargination; basal mesotarsomeres with brush of tenent setae (not flattened into broad pad); parameres fused, without peg setae, with base of paramere visible and not fused to median lobe; aedeagus with internal sac bearing strongly sclerotized, broad dorsal band; internal sac with ventral paired copulatory sclerite, two-pronged copulatory piece and external copulatory plate absent.

Distribution

Afroquedius is distributed in montane forests of eastern and southern South Africa ( Solodovnikov, 2006), whereas Valdiviodes is distributed in Valdivian temperate rainforests of Chile ( Smetana, 1981). The disjunct distribution across Gondwanan landmasses is likely to be a result of vicariance based on divergence date estimates for Staphylinini ( Brunke et al., 2017a) .