taxonID	type	description	language	source
039887A4FFD1180DFEA5FB33FB5AFF1C.taxon	materials_examined	Type genus: Clidicus Laporte, 1832. Diagnosis Clidicini, restricted here to Clidicus and † Palaeoleptochromus (which may be a synonym of the former), are defined by the following unique apomorphies: some setae on frons and vertex conspicuously long and erect among much shorter and denser basic vestiture, and one or two conspicuously long and erect ventral setae present in basal half of profemur; and a set of synapomorphies (known in other tribes, but in a different combination): only scape enlarged and longer than head; head capsule about as long as broad or slightly transverse; antennal insertions broadly separated; occipital constriction about half as broad as width of head or narrower; eyes small, much shorter than tempora; maxillary palpomere 4 subtriangular; pronotum with posterior collar separated by transverse row of pits; mesoventral intercoxal process narrow, carinate, with subparallel lateral margins; admetacoxal margin of metaventrite with an angulate expansion; elytral rows of punctures distinct; abdominal sternite 6 not emarginate.	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFD31808FC24F931FDF6FDAD.taxon	discussion	Remarks † Palaeoleptochromus, with its sole species † P. schaufussi from the Campanian of Canada, is the most problematic extinct taxon of Mastigitae. Most characters crucial to place it in a taxonomic context are not observable in the specimen. In our analysis it was placed within the poorly resolved Clidicini sensu nov. (Fig. 3). † Palaeoleptochromus may be a junior synonym of Clidicus, and as the only North American member of this lineage, represents the only firm evidence for a broad distribution of Clidicini during the Upper Cretaceous. However, the fossil has an intriguing character, not known in any remaining Clidicini – a pair of enlarged setae on the posterior margin of the vertex (illustrated in O’Keefe et al., 1997). The placement of † Palaeoleptochromus is still unclear, so we retain this name as valid, pending further study.	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFD41808FF1AFD70FB67FC3C.taxon	materials_examined	Type genus: Papusus Casey, 1897, here designated. Diagnosis Papusini differs from all remaining Mastigitae genera by the unique, very large compound eyes located at the middle, or slightly behind the middle, of the head capsule, and a set of synapomorphies known (in different combinations) in other tribes: scape about as long as head, lacking bristles; pedicel not enlarged; maxillary palpomere 3 strongly elongate, with its apical margin nearly perpendicular to the long axis of palpomere, gradually broadening distally; maxillary palpomere 4 subtriangular, broadest at base, much shorter than 3 and distinctly narrower than 3 at apex; vertex and frons lacking median longitudinal groove; posterior margin of vertex lacking a pair of modified setae or large chaetopores; pronotum lacking posterior collar; mesoventral intercoxal process elongate, slender and parallel-sided; posterior margins of mesocoxal cavities carinate; mesocoxa with longitudinal row of several (typically 5) long and thick bristles; admetacoxal margin of metaventrite at each side with indistinct expansion (i. e. not evenly concave but slightly angulate near the mesal third of metacoxa); elytra with longitudinal rows of shallow punctures; aedeagus symmetrical, with slender parameres and straight flagellum. Remarks The placement of Papusus has been problematic for the past 120 years. Casey (1897) placed it in Clidicini, based on a similar form of the maxillary palpomere 4 of Papusus to that of Clidicus. Franz (1985) transferred Papusus to Scydmaenini of Scydmaenitae, but later synonymized it under Leptochromus, automatically moving it back to Clidicini. Papusus was resurrected as a valid name and separate genus by O’Keefe (1998), who carried out a phylogenetic analysis focused on resolving relationships between species of Papusus, but used only Leptochromus as the outgroup. Later, O’Keefe (2002) proposed a sister-group relationship between Papusus and († Palaeoleptochromus + Leptochromus), but his analysis was restricted to three genera only, with Clidicus as the outgroup. A broader taxon sampling was done by Jałoszyński (2012 a, 2016 b), who included all genera of Mastigitae known at that time and obtained ambiguous results concerning the placement of Papusus. It was placed, with equal parsimony, as (1) a sister-group to all remaining Clidicini (in a broad, traditional sense) vs. (2) sister to Leptomastacini + all remaining Clidicini (Jałoszyński, 2012 a), or as (3) sister to Leptomastacini vs. (4) sister to a clade Clidicus + (remaining Clidicini + Mastigini) (Jałoszyński, 2016 b). Consequently, Papusus remained the most problematic of all extant genera and its placement was unclear. Papusus was not placed together with the remaining genera traditionally placed in Clidicini in our phylogenetic reconstructions (neither in parsimony nor in Bayesian analyses), and although its relationships within Mastigitae are still far from being solved, it is clear that Papusus cannot be maintained as a member of Clidicini, based on: the emarginate male sternite 8; the absence of a pronotal collar; uniform setae on frons, vertex and maxillary palpomere 2; narrowly separated antennal cavities; and the presence of a row of mesocoxal bristles.	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFD41809FCE6FBF6FD9CFACA.taxon	materials_examined	Type genus: Leptochromus Motschulsky, 1855, here designated. Diagnosis Leptochromini differs from all remaining Mastigitae in a unique apomorphy: protrochanteral ventral comb of several (2 – 7) thick bristles; postgenal bristles are also most likely an autapomorphy of Leptochromini (see Remarks below); and a set of synapomorphies shared with members of other tribes (but in different combinations): scape longer than head, lacking bristles; pedicel unmodified; head capsule strongly transverse; maxillary palpomeres 2 and 3 strongly elongate, palpomere 4 shorter than 3, variable in shape, suboval, subtriangular or nearly rod-like; pronotum with distinct posterior collar; elytra with distinct rows of punctures; mesoventral intercoxal process narrow and elongate, subparallel or slightly narrowing posteriorly; abdominal sternite 8 in males emarginate at middle (this character state remains unstudied in fossils); aedeagus symmetrical or nearly symmetrical, with straight flagellum (also not known in fossils). Remarks Postgenal bristles in our analyses were coded assuming their homology in members of the newly defined tribe Leptochromini and Clidicus formicarius, † Palaeoleptochromus schaufussi, † Cretoleptochromus archaicus and † Cretoleptochromus burmiticus. The previous placement of all these genera (except † Cretoleptochromus treated as incertae sedis) in Clidicini suggested such a homology, with thick postgenal bristles of Leptochromus, † Euroleptochromus and † Rovnoleptochromus presumably developed from sparse and conspicuously long, erect setae present in the same area in some species of the Clidicus / † Cretoleptochromus / † Palaeoleptochromus lineage. However, the topology obtained in our parsimony analysis and reconstruction of ancestral character states falsified this hypothesis, in favour of a parallelism, i. e. an independent evolution of long setae and bristles in Clidicini sensu nov. and Leptochromini. Whether Leptochromini represents the sister-group of † Baltostigini + Mastigini (resolved but unsupported in parsimony analysis) or Clidicini (as found in the Bayesian analysis, but without support, PP = 0.59) remains an unsettled issue. However, the genera placed in Leptochromini form a monophyletic morphological unit in topologies obtained in both analyses, and for this reason they are placed in a separate tribe. Defined as above, Leptochromini differs from Clidicini sensu nov. in the presence of a protrochanteral ventral comb of thick bristles; presence of postgenal bristles (conspicuously thicker than long setae in Clidicini); maxillary palpomere 4 slightly broadening distad, at least in basal half; and abdominal sternite 8 in males emarginate at middle (but not known in fossils). Moreover, the strongly transverse head capsule in Leptochromini (Fig. 1 C, D) clearly differs from the subrectangular or subtrapezoidal and weakly transverse head of Clidicini (Fig. 1 A, B).	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFD5180BFED1FA4EFB2EFE75.taxon	description	(FIG. 7 A – J) urn: lsid: zoobank. org: act: 9209 EBD 8 - D 459 - 46 E 8 - 9108 - 7 BC 08 F 2 E 55 CE Type material Holotype (CCHH 835 - 3), from Baltic amber (Russia, Kaliningrad); female (confirmed by μCT scan of postabdomen), preserved in a rectangular prism (7 × 6 × 3.5 mm) of amber (CCHH / SDEI). Diagnosis Protrochanter of female subtriangular, with apical bristle and single apical seta as long as trochanter; elytral index <1.7; pronotum strongly elongate, pronotal index nearly 1.3; scape nearly 3.7 times as long as pedicel, each of antennomeres 4 – 7 at least 1.25 × as long as scape. Description Body (Fig. 7 A, E – G) slender, length 3.08 mm, dark brown. Head (Fig. 7 B, H, I) strongly transverse, length 0.45 mm, width 0.58 mm; occipital constriction (Fig. 7 I) about half as wide as width of head, vertex strongly transverse, indistinctly impressed medially and anteriorly confluent with strongly transverse frons; eyes large and strongly projecting from the silhouette of the head; postgenal process (Fig. 7 B, E, F, I) nearly 3 × as long as broad, with two long and divergent apical bristles. Submentum (Fig. 7 I) strongly transverse, demarcated laterally by weakly sinuate and complete hypostomal ridges. Maxillary palp (Fig. 7 B, I) much longer than head, palpomere 2 much longer than 3 but shorter than 3 and 4 combined, divided by angulate expansion located in proximal 0.4 into two unequal parts, proximal part distinctly curved, distal part nearly straight and slightly broader, angulate expansion with one robust anterior bristle; palpomere 3 slender, nearly cylindrical in basal half and then gradually broadening distad; palpomere 4 as long as 0.35 of palpomere 3, suboval. Punctures and setae on frons and vertex fine, inconspicuous. Antennae much shorter than body, length 2.26 mm, relative lengths of antennomeres (the shortest antennomere 3 as 1): 4: 1.09: 1.00: 1.45: 1.45: 1.36: 1.36: 1.27: 1.09: 1.09: 1.27. Antennomeres sparsely covered with suberect setae of various lengths. Pronotum (Fig. 7 D, E, G) elongate and broadest distinctly in front of middle, length 0.88 mm, width 0.68 mm, pronotal index 1.29; disc convex and sparsely covered with shallow but distinct punctures (those near middle separated by spaces 2 – 3 times as wide as diameters of punctures), setae indiscernible; posterior collar demarcated by transverse row of four dorsal pits, additionally one laterodorsal pit located at each side of pronotum; posterior pronotal margin with narrow groove. Prosternum (Fig. 7 F) with basisternal part about as long as procoxae, lacking discernible traces of notosternal sutures, procoxae contiguous. Mesoventral intercoxal process (Fig. 7 J) carinate, parallel-sided, weakly elevated. Metaventrite (Fig. 7 F) slightly impressed posteromedially, metacoxae broadly separated. Elytra (Fig. 7 E, G) strongly convex, broadest near middle, length 1.75 mm, width 1.08 mm, elytral index 1.63; each elytron with four dorsal and two lateral rows of distinct, large punctures; humeral calli prominent, elongate; elytra sparsely covered with short suberect setae. Legs (Fig. 7 A, C, E, F) long and slender, protrochanters (Fig. 7 A, C) elongate and subtriangular, each with moderately long apical spine, extremely long, thin apical seta and 3 – 4 moderately long, thin subapical setae; profemur (Fig. 7 C) with four long ventral spines, insertions of the first two spines touching each other, additionally profemur with several long and thin ventral setae; protibiae strongly curved; remaining legs unmodified. Etymology The name setifer (treated here as a noun in apposition) refers to the unusually long seta on each protrochanter. Type locality and horizon Russia, Kaliningrad; Upper Eocene. Remarks Apart from the female trochanter, this species differs from the previously known † E. sabathi in the elytral index 1.63 (1.74 in † E. sabathi), a much more elongate pronotum (pronotal index 1.29 vs. 1.00 in † E. sabathi), the scape 3.67 times as long as pedicel (only 2.94 times in † E. sabathi) and each of antennomeres 4 – 7 at least 1.25 times as long as scape (0.94 – 1.06 times in † E. sabathi). In all other characters these two upper Eocene species are very similar. Results of the μCT scan of † E. setifer demonstrated for the first time that strongly curved protibiae in † Euroleptochromus are not male secondary sexual characters, but occur in females (no traces of the aedeagus were found inside the abdomen). This interesting character is, therefore, the same as in the extant and closely related Leptochromus, in which males and females have curved protibiae, and unlike extinct and extant Mastigini, where this character state is restricted to males of some species. Moreover, the μCT technique revealed structures impossible to observe in the inclusion under light microscopy, e. g. the shape of the hypostomal ridges (Fig. 7 I) or the intermesocoxal region of the mesoventrite (Fig. 7 J). A very similar specimen (CCHH 835 - 2, deposited in CCHH / SDEI; Supporting Information, Fig. S 6) from the same deposit of Baltic amber (Russian, Kaliningrad) was also studied. It shows some of the diagnostic characters of † E. setifer, i. e. the subtriangular protrochanter with an extremely long apical seta, but it is slightly larger (body length 3.23 mm) and has slightly different proportions of antennomeres, especially the longer scape (4.14 × as long as pedicel versus 3.67 × in † E. setifer). This inclusion may represent a separate species, but the opaque, milky amber obscuring the body surface, the position of the beetle inside the amber piece and the partly air-exposed surface make it difficult to measure widths of the pronotum and elytra, important for the diagnosis. This specimen does not add any novel characters to the diagnosis of † Euroleptochromus, but demonstrates a considerable variability in the relative length of the scape and pedicel within the genus. All these fossils (i. e. the holotypes of † E. sabathi, † E. setifer and specimen CCHH 835 - 2), as well as † Rovnoleptochromus, have prominent humeral calli (well-visible in Fig. 7 E), typical of winged beetles, but hind wings are not observable in any of them. Their closest living relatives, species of Leptochromus, have similarly large and well-defined humeral calli and are winged, suggesting that Eocene species of Leptochromini were capable of flight.	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFD71814FCEBFE27FF3DFBD0.taxon	materials_examined	Type genus: Baltostigus Jałoszyński, 2016, here designated. Diagnosis Baltostigini differ from all remaining tribes in a unique combination of synapomorphies: maxillary palpomere 3 subtriangular, gradually broadening distally; palpomere 4 axe-shaped, broader than long and broadening distally; both scape and pedicel enlarged and bearing ventral spines; head capsule elongate; vertex evenly convex, not impressed posteromedially and lacking median longitudinal groove; pronotum lacking posterior collar; elytra with rows of punctures at least in anterior half; wings developed; mesoventral intercoxal process carinate and parallel-sided; aedeagus symmetrical, with both parameres equally well-developed. Remarks	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFCA1816FF43FED1FE54FD53.taxon	materials_examined	Type genus: Mastigus Latreille, 1802. Diagnosis Mastigini are restricted here to genera sharing: an enlarged and ventrally spiny scape and pedicel; elongate head with median longitudinal groove on posteriorly impressed vertex; narrowly separated antennal insertions; pronotum lacking posterior collar; and aedeagus asymmetrical, with one paramere distinctly shorter than the other one (in some cases only one paramere is visible, the other one is either vestigial or completely obliterated).	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
039887A4FFCA1816FF1BFCFDFDDDFB9C.taxon	discussion	Remarks † Cascomastigus does not differ in any characters from † Clidicostigus; their diagnostic features, including uniquely shaped maxillary palps with an asymmetrical palpomere 4, and elytral striae, are identical. Neither structural nor spatiotemporal arguments support a separate placement of these taxa, and † Cascomastigus is here placed as a junior synonym of † Clidicostigus (the former name with the online publication date 2017.03.07; the latter 2017.01.03).	en	Jałoszyński, Paweł, Brunke, Adam J., Yamamoto, Shûhei, Takahashi, Yui (2018): Evolution of Mastigitae: Mesozoic and Cenozoic fossils crucial for reclassification of extant tribes (Coleoptera: Staphylinidae: Scydmaeninae). Zoological Journal of the Linnean Society 184: 623-652
