Clidicini Casey
Creators: name: Paweł Jałoszyński
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy

description: Tribe Clidicini Casey
Clidicinae Casey, 1897: 541. Type genus: Clidicus Laporte de Castelnau, 1832.
Clidicini Ganglbauer, 1899: 60. Type genus: Clidicus Laporte de Castelnau, 1832. Tribe redefined by Jałoszyński et al. (2018).
Diagnosis. Clidicini differ from all other Mastigitae in two unique apomorphies: some setae on frons and vertex conspicuously long and erect among much shorter and denser basic vestiture (Fig. 84, but in some species indistinct); one or two conspicuously long and erect ventral setae present in basal half of each profemur (reduced in some species); and a combination of synapomorphies that can be found in other tribes and genera, but not occurring all together: only scape enlarged and as long as head or (more frequently) longer (e.g., Fig. 84); head capsule about as long as broad or slightly transverse (e.g., Fig. 90); antennal insertions broadly separated (e.g., Fig. 90); occipital constriction about half as broad as width of head or narrower (e.g., Fig. 90); eyes small, much shorter than tempora, anterior (e.g., Fig. 90); hypostomal ridges nearly reaching posterior tentorial pits; maxillary palpomere IV subtriangular (e.g., Fig. 93); mandibles with at least three (usually more) subapical teeth of various lengths, some located above, and some beneath the coronal plane of mandible (Fig. 92); pronotum with posterior collar demarcated by a transverse row of pits (e.g., Figs 78–79); mesoventral intercoxal process narrow, carinate, with subparallel lateral margins (Fig. 97); metacoxal margin of metaventrite with an angulate adcoxal expansion at each side (Fig. 97); metaventrite lacking foveae; elytral rows of punctures deep, distinct and regular (Figs 78–83); abdominal sternite VIII in males not emarginate; aedeagus heavily sclerotized and in repose positioned symmetrically inside abdomen; larva with subtrapezoidal head with short annular 'neck', each larval mandible with a preapical tooth, larval antennomere II undivided, larval antennomere III much longer than broad, sensory appendage spatulate, urogomphi present.
Characteristics. Adults. Body (Figs 78–83, 86–88) small to large, in extant species 2.99̄8.5 mm in length, in nominal extinct species 2.23–7.33 mm, typically from light to dark, often reddish brown, in one species red with dark brown head; strongly convex, dorsally densely setose, setae typically conspicuously long and erect, unmodified except for variously developed longer and more erect bristles distributed on antennae, maxillary palps, head capsule and legs.
Head capsule (Figs 84–85, 90–91) divided into large and exposed anterior part and much smaller, subcylindrical 'neck' region retracted into prothorax and demarcated by distinct occipital constriction; 'neck' region about as broad as half width of head. Anterior part of head strongly flattened, typically subequal in width with prothorax, weakly transverse or (rarely) about as long as broad, broadest behind middle or (rarely) at middle. Composite eyes dorsolateral, near anterior margin of head, small but composed of numerous small ommatidia, weakly convex. Vertex strongly transverse and posteriorly impressed at middle, convex at sides, with posterior margin concave; in one problematic extinct genus with a pair of long posterolateral setae. Tempora long and rounded. Frons between antennal insertions broadly subtrapezoidal, not forming a demarcated 'platform', anteriorly demarcated by a deep and complete frontoclypeal groove (Fig. 90; fcg). Clypeus very short and broad, with rounded or straight sides. Antennal insertions (Fig. 90; ai) located anterodorsally, broadly separated. Gular plate (Fig. 91; gp) lacking sutures, nearly smooth; posterior tentorial pits (Fig. 91; ptp) arcuate, in front of transverse impression demarcating 'neck' region ventrally; hypostomal ridges (Fig. 91; hr) nearly straight or arcuate, posteriorly nearly reaching posterior tentorial pits. Head with or without punctures, densely setose, often with conspicuously long setae (Fig. 84).
Antennae (Figs 78–88, 95) shorter or about as long as body, slender; scape (Fig. 95; sc) 4̄6 times as long as broad, usually slightly broadening distad, with very deep lateroventral emargination; pedicel (Fig. 95; pd) typically shorter than, or less frequently about as long as antennomere III and broadening from narrow base to apex; antennomeres III–X elongate (usually strongly, less frequently weakly) and weakly thickening distad, basal stalks not exposed, basal rings absent or indistinct; antennomere XI elongate and slightly asymmetrical. Antennomeres covered with variously dense, long setae; surface of antennomeres in most specimens smooth.
Mouthparts. Labrum (Fig. 92; lbr) strongly transverse, variable in shape, with lateral margins parallel or (more frequently) divergent anterad, nearly straight or rounded, and with anterior margin straight, concave, emarginated or notched at middle, or with a row of variously shaped anterior teeth or denticles, with a transverse dorsoanterior row of long setae. Mandibles (Figs 90–92) symmetrical, subtriangular and robust, with at least three (usually more) subapical teeth of various lengths, some located above, and some beneath the coronal plane of mandible, setose prostheca present and long. Maxilla (Fig. 94) with large but relatively short cardo (Fig. 94; cd); basistipes (Fig. 94; bst) subtriangular and elongate; mediostipes (Fig. 94; mst) large and sharply demarcated from lacinia (Fig. 94; lac) and galea (Fig. 94; gal), which are both elongate and curved mesally and each with a dense row of distal setae; palpifer (Fig. 94; ppf) broad and elongate; maxillary palp (Figs 84–85, 93–94) composed of minute palpomere I, elongate and broadening distad palpomere II, palpomere III (Fig. 93; mxp3) subtriangular, broadening distad, with oblique distal margin, palpomere IV (Fig. 93; mxp4) subtriangular, with pointed apex, its base typically narrower than apex of palpomere III or subequal in width; palpomeres III and IV often somewhat flattened. Maxillary palps can be much longer than head capsule (Fig. 84) or about as long as head (Fig. 85), typically in strongly elongate species with very slender antennae and legs also palps are long and slender (Fig. 82), and in those with relatively stout body and short antennae and legs (Fig. 80) the palps are proportionally shorter and with broader palpomeres III and IV. All palpomeres densely covered with variously long setae, palpomere II and/or III with some long and more erect setae among suberect and shorter basic vestiture (well-visible in Fig. 84, in some species indistinct). Labium (Figs 91–94) with broad submentum (Fig. 91; smn) posteriorly not demarcated from gular region, bearing a pair of long thin setae near its anterior margin or in subanterior region; mentum (Fig. 94; mn) subtrapezoidal and strongly transverse, with anterior margin straight or broadly rounded; prementum (Fig. 94; pm) long, subtrapezoidal, broadest distally, lacking demarcated ligula, with a pair of anterolateral setae, with broadly separated bases of labial palps; lateral hypopharyngeal lobes (Fig. 94; lhl) moderately large; labial palp (Fig. 91; lp) composed of three palpomeres: palpomere I (Fig. 94; lp1) small, elongate, broadening distad, palpomere II (Fig. 94; lp2) largest, strongly elongate and only indistinctly broadening distad, only in one problematic extinct taxon narrow at base and strongly broadened in distal half, palpomere III (Fig. 94; lp3) narrow, long and pointed, in one problematic extinct taxon extremely slender, bristle-like. Porous fields on mouthparts and clypeus not found.
Prothorax (Figs 78–85, 96) about as long as broad or elongate, strongly convex, broadest near anterior third. Pronotum with anterior and posterior margins arcuate or nearly straight, sides rounded in anterior half and usually sinuate in posterior half; anterior corners broadly rounded, posterior corners obtuse-angled; pronotal base with a short posterior 'collar' demarcated by a dorsal transverse row of several variously distinct pits, often connected by a groove. Prosternum (Fig. 96) with basisternal part (Fig. 96; bstr) subequal in length to coxal part, but proportions depend on the shape of pronotum, in species with short pronota the basisternal part tends to be indistinctly shorter than coxal part, in species with elongate pronota the basisternal part can be longer than coxal part. Prosternum laterally completely fused with hypomera. Coxal region demarcated anteriorly by carina extending laterally up to apices of very weakly developed adcoxal hypomeral lobes. Procoxal cavities broadly open. Prosternal intercoxal process indistinct, usually developed as a diffuse and weakly elevated ridge hidden between procoxae. Ventral surface of prothorax typically densely setose.
Mesoventrite (Figs 84–85, 97) subtrapezoidal, broadening posteriorly. Prepecti (Fig. 97; pre) long and together with anteromedian mesoventral area forming a massive 'collar', which bears a transverse groove just behind its anterior ridge (Fig. 97; ar), its posterior margin bisinuate with short subtriangular or subtrapezoidal posteromedian projection, which is broadly separated from a similar anteromedian projection of posterior margin of setose impression (Fig. 97; si). Region just behind collar strongly and abruptly constricted, ventrally forming setose impression (Fig. 97; si) filled with dense, unmodified setae. Mesoventral intercoxal process (Fig. 97; msvp) long, narrow and weakly convex, nearly parallel-sided or indistinctly broadened near middle of mesocoxal cavities, fully separating mesocoxae, posteriorly fused with metaventrite or with variously distinct posterior tip. Mesanepisterna large and subtriangular; mesepimera (Fig. 97; epm2) partly exposed in ventral view.
Mesonotum with subtriangular, elongate mesoscutellum with rounded apex, in intact specimens only its very tip visible between elytral bases; scutoscutellar suture absent.
Metanotum fully developed or somewhat reduced, with alacristae not or only slightly shortened; hind wings present or absent.
Metaventrite (Fig. 97) short, subquadrate or subrectangular and slightly transverse, with lateral margins rounded; each mesocoxal cavity with posterior marginal carina, anterior margins not carinate; posterior margin of metaventrite deeply bisinuate laterally (in front of each metacoxa) and with a broad metaventral intercoxal process (Fig. 97; mtvp) with variously deeply concave posterior margin and subtriangular posterolateral corners; metaventrite lacking foveae. External admetacoxal part of posterior metaventral margin with additional marginal thickening demarcated by a groove, forming adcoxal carina (Fig. 97; acxc) at each side. Metanepisterna (Fig. 97; aest3) broad and partly visible in ventral view, broadened posteriorly; metepimera broader than metanepisterna, with indistinctly demarcated inner and outer component, posteriorly extending far behind metacoxae. In one extinct species metaventrite with longitudinal median carina.
Metendosternite (metafurca) Y-shaped, with short but distinct stem and divergent lateral furcal arms.
Legs (Figs 78–88, 97) long and slender, often conspicuously so. Pro- and mesocoxa short subconical, metacoxa with nearly hemispherical basal part and subconical distal part. Mesocoxa lacking coxal bristles, but often with a comb of thin long setae. All trochanters short and subtriangular. Femora weakly clavate, profemur typically with at least one conspicuously long and erect ventral seta (rarely setae reduced). Tibiae robust, protibiae often curved in distal third or fourth. Tarsi long and slender, nearly subcylindrical, tarsomeres I–V subequal in length or reducing in length, tarsomere V strongly elongate, with curved and slender claws lacking elongate costae; empodial region was not studied.
Elytra (Figs 78–83) oval, strongly convex, with variously distinct humeral calli, lacking basal impressions, with rounded or pointed apices; elytral disc with distinct large and deep punctures arranged in nearly complete and regular longitudinal rows. Elytra variously densely setose, setae typically long and erect.
Abdomen with sternite III not fused with metaventrite, about as long as sternites IV and V together; sternite VIII in male with rounded posterior margin.
Aedeagus (illustrated in Besuchet (1971), Jałoszyński (2009, 2018), O’Keefe & Monteith (2000), Orousset (2014), Zhou & Li (2015)) strongly elongate, with symmetrical median lobe, parameres heavily sclerotized, symmetrical or one longer than the other; flagellum simple, not coiled, but often broadened and forming a sac-like structure. Ejaculatory duct with elongate and narrow sperm pump, typically with funnel-like structures at both ends, but in some species with one or both funnels absent. Aedeagus in repose positioned symmetrically inside abdomen, with basal orifice facing up.
Spermatheca (illustrated e.g., by Orousset (2014)) globular, variable in shape, in some species nearly spherical, in others elongate, thick-walled, with relatively large accessory gland.
Characteristics. Larvae. Only a larva of the Australian Clidicus abbotensis O'Keefe, 2000 was described (O’Keefe & Monteith 2000); characteristics given at Clidicus.
Composition and distribution. Clidicini, as currently defined, comprise 32 extant and extinct species classified in three genera. The extant species are distributed (Fig. 89) in the Oriental region and northern Australia; definitive fossils come from Cenomanian of Myanmar and Priabonian of central-eastern Europe. Extinct taxa that may belong to Clidicini are known from Upper Eocene Baltic amber, Lower Cretaceous Charentese French amber and Middle Miocene Chiapas amber.
Remarks. Historically, Clidicini included Clidicus, Leptochromus, Papusus, and later also several extinct genera. Jałoszyński et al. (2018) redefined this tribe and restricted it only to Clidicus, with the problematic Middle Miocene Palaeoleptochromus placed in this tribe tentatively and pending further study. The same applies to the Upper Eocene Aenictosoma known from Baltic amber, which was originally described as possibly belonging to Cerambycidae (Schaufuss 1891), and later, solely on the basis of the original description, transferred to Scydmaeninae: Clidicini (Vitali 2006). See Remarks for each of these taxa below.
description: Published as part of Paweł Jałoszyński, 2018, World genera of Mastigitae: review of morphological structures and new ecological data (Coleoptera: Staphylinidae: Scydmaeninae), pp. 1-119 in Zootaxa 4453 (1) on pages 38-40, DOI: 10.11646/zootaxa.4453.1.1, http://zenodo.org/record/1454920