' The curse of Horaeomorphus ': taxonomy of misplaced Australian Cyrtoscydmini (Coleoptera: Staphylinidae: Scydmaeninae)
Jałoszyński, Paweł
Zootaxa
2014
3828
1
1
76
[151,320,439,465]
Insecta
Staphylinidae
Sciacharoides
Animalia
Coleoptera
49
50
Arthropoda
genus
gen. nov.
Typespecies: Horaeomorphus thompsoni Franz, 1975: 145(here designated).
Diagnosis.Body ( Figs. 160–163) stout to moderately elongate, moderately to strongly convex; head short and convex; vertex not projecting dorsocaudad, its posterior margin slightly convex, nearly straight or slightly concave; supraantennal tubercles from barely discernible to feebly raised, not accompanied posteromesally by pits; frontoclypeal groove absent; eyes located in anterior or median part of head; tempora long and strongly curved toward occipital constriction; tempora, genae and postgenae with moderately dense bristles; 'neck region' distinctly demarcated from anterior part of head capsule by constriction and much narrower than vertex; hypostomal ridges ( Fig. 129; hr) sharply marked just behind cardines and variously long, extending at least to middle between anterior margin of submentum and posterior tentorial pits or farther up to posterior tentorial pits, not connected in middle; posterior tentorial pits ( Fig. 129; ptp) elongate and located distinctly in front of transverse groove demarcating 'neck' ventrally; submentum ( Fig. 129; smn) without lateral sutures; each mandible subtriangular, with variously developed subapical tooth, from rudimentary ( Fig. 132, 151) to distinct ( Fig. 142; sat) but always small, and with densely setose mesal prostheca ( Fig. 132; pst); maxillary palpomeres III and IV ( Fig. 133; mxp3–4) slender, strongly elongate; pronotum with various antebasal sculpture ( Figs. 135, 145, 154) composed of pits or/and transverse groove, without sublateral carinae and lateral edges; prosternum laterally demarcated from hypomera by pronotosternal sutures ( Fig. 134; nss), in middle between procoxal cavities ( Fig. 134; pcc) variously distinctly raised and forming low and elongate intercoxal carina; procoxal sockets ( Fig. 134; pcs) closed by posterolateral lobes of prosternum; prothoracic hypomera ( Fig. 134; hy) with large internal (adcoxal) parts demarcated from sides of pronotum by hypomeral ridges that can be nearly complete ( Fig. 134; hyr) or indistinct in median ( Fig. 153; hyr) or median and posterior portion ( Fig. 146; hyr); sides of pronotum with variously dense thick bristles ( Figs. 134, 146, 153) well visible in dorsal view; mesoventrite with short anterior ridge ( Fig. 137; ar) medially connected with mesoventral process ( Fig. 137; msvp) which is narrow and weakly expanding ventrally and reaching only to anterior margin of mesocoxal cavities, so that mesocoxae are not separated; ventrolateral mesothoracic foveae ( Fig. 139; vlf) present, dorsolateral foveae absent; anterior metaventral process absent; metaventral intercoxal process ( Fig. 140; mtvp) broadly subtriangular, without median notch; metacoxae ( Fig. 138; cx3) contiguous or nearly contiguous; each elytron ( Fig. 136; bef) with two asetose rudiments of basal foveae not connected by groove and barely discernible or not discernible in dry-mounted specimens; aedeagus ( Figs. 168–173) with free and slender parameres.
Description.Body ( Figs. 160–163) moderately large (BL 1.45–1.85 mm), relatively stout, with long appendages, pigmentation brown, cuticle setose. Head ( Figs. 129, 141, 148) with occipital constriction ( Figs. 129, 141, 148; occ) much narrower than vertex and dividing head capsule into exposed anterior part and narrow posterior 'neck region' retracted into prothorax; eyes located in anterior part of head or nearly in middle, oval or kidney-shaped, weakly protruding from the head silhouette; tempora long and strongly curved posteromesally, with sparse bristles; vertex transverse, uniformly convex, not projecting dorso-caudad, with posterior margin nearly straight or slightly concave; frons confluent with vertex, transverse and subtrapezoidal; frontoclypeal groove absent; antennal insertions broadly separated, located beneath distinct but weakly raised supraantennal tubercles. Labrum ( Figs. 131, 142, 150) transverse, subtrapezoidal ( Fig. 131), subrectangular ( Fig. 142) or semioval ( Fig. 150), with straight or slightly emarginate anterior margin, with short and dense lateral groups of anteroventral setae ( Fig. 131), or long and dense anterior setae ( Fig. 142), or six pairs of thick and pointed anteroventral sensilla ( Fig. 150) projecting from beneath anterior margin, and with small number of long dorsal setae. Mandibles ( Figs. 132, 143, 151) symmetrical, subtriangular, each with broad base and one variously distinct subapical tooth, from rudimentary ( Figs. 132, 151) to small but distinct ( Fig. 143); setose prostheca ( Figs. 132, 143, 151; pst) present, mesal, not expanding onto dorsal surface of mandible and reaching mandibular base. Each maxilla composed of small cardo ( Figs. 129, 141, 148; cd) bearing two setae; subtriangular basistipes ( Figs. 133, 144, 152; bst); elongate mediostipes ( Figs. 133, 144, 152; mst); elongate galea ( Figs. 133, 144, 152; gal) and lacinia ( Figs. 133, 144, 152; lac); large, elongate palpifer ( Figs. 133, 144, 152; pfp); and strongly elongate and moderately large maxillary palp ( Figs. 129, 141, 148; mxp) composed of elongate palpomere I ( Figs. 129, 141, 148; mxp1), strongly elongate, slightly clavate and slender palpomere II ( Figs. 129, 141, 148; mxp2), large and strongly elongate, slender palpomere III ( Figs. 129, 141, 148; mxp3) broadest near middle or in distal third, and small, slender, subconical and pointed palpomere IV ( Figs. 129, 141, 148; mxp4). Labium ( Figs. 129–130, 141, 148–149) with large submentum ( Figs. 129, 141, 148; smn) not demarcated laterally from postcardinal parts of hypostomae; subtrapezoidal mentum ( Figs. 129, 141, 148–149; mn); and short prementum ( Fig. 141; pmn) bearing narrowly separated at bases long 3- segmented labial palps ( Figs. 129, 141, 148; lp) and a pair of long lateral bristles inserted on small subrectangular or inversely subtriangular ligula ( Figs. 130, 141, 149; lg); additionally ligula with 2–4 short setae in middle. Hypostomal ridges ( Figs. 129, 141, 148; hr) sharply marked, extending to middle of distance between anterior margin of submentum and posterior tentorial pits ( Figs. 129, 149) or farther ( Fig. 141) nearly up to posterior tentorial pits, but not connecting in middle. Gular plate ( Figs. 129, 141, 148; gp) large and subtrapezoidal, with rapidly narrowed anterior part (between transverse impression in front of 'neck region' and posterior tentorial pits; lateral margins of this anterior part of gular plat are not marked); gular sutures ( Figs. 129, 141, 148; gs) superficial; posterior tentorial pits ( Figs. 129, 141, 148; ptp) narrow and straight or slightly arcuate, located clearly in front of transverse impression ventrally demarcating 'neck region'. Antennae ( Figs. 160–163) moderately long and slender, gradually and only slightly thickening distally or with indistinct club composed of five terminal antennomeres; antennomere XI unremarkable. Prothorax ( Figs. 134–135, 145–146, 153– 154, 160–163) in dorsal view slightly to strongly elongate and broadest near anterior third, with rounded anterior margin and anterior parts of lateral margins, with barely marked, blunt and strongly obtuse anterior corners; posterior corners distinct, obtuse; posterior margin nearly evenly arcuate or shallowly bisinuate. Pronotum without sublateral carinae, with transverse groove ( Figs. 135, 145, 154; tg), in some species accompanied by internal and lateral pair of pits ( Fig. 135; ip, lp) or interrupted in middle ( Fig. 135). Sides of pronotum with thick and sparse bristles ( Figs. 134, 146, 153). Prosternum with short basisternal part ( Figs. 134, 146, 153; bst) distinctly demarcated from procoxal cavities ( Figs. 134, 146, 153; pcc); median part of sternum with narrow and variously distinct prosternal intercoxal carina; procoxal sockets ( Figs. 134, 146, 153; pcs) closed by posterolateral lobes of prosternum; hypomera ( Figs. 134, 146, 153; hy) elongate, each divided into broad lateral part confluent with pronotum and narrower internal (adcoxal) part; hypomeral ridges ( Figs. 134, 146, 153; hyr) weakly marked in median and/or posterior portion; pronotosternal sutures ( Figs. 134, 146, 153; nss) entire. Mesoscutellum ( Fig. 155; scl2) subtriangular, in intact specimens hidden by posterior margin of pronotum overlapping with elytral base; mesoscutoscutellar suture ( Fig. 155; sss) present. Mesoventrite with narrow and distinctly demarcated anterior ridge ( Figs. 137, 147, 156; ar); mesoventral process ( Figs. 137, 147, 156; msvp) carinate and moderately expanding ventrally, anteriorly connected with anterior ridge and not reaching anterior margins of mesocoxal cavities, so that mesocoxae are not separated; sides of mesoventrite with shallow procoxal rests ( Figs. 137, 147, 156; pcr) filled with bristles (= setose impressions) but without asetose impressions; mesanepisternum with short prepectus ( Figs. 137, 147, 156; pre), sides of mesoventrite with narrow but deep setose ventrolateral foveae ( Figs. 139, 147, 158; vlf, dlf); dorsolateral foveae absent; mesocoxal projections ( Figs. 137, 147, 156; mcp) prominent, with mesocoxal sockets located on their mesoventral surface and visible in ventral view. In one species mesanepisterna each with thick and long bunch of dense setae ( Fig. 147; seb), under stereoscopic microscope appearing as solid projection ( Fig. 162). Metaventrite ( Figs. 138–139, 147, 157–158; v3) subrectangular, anteriorly fused with mesoventrite, posteriorly nearly straight with broadly subtriangular and rounded metaventral intercoxal process ( Figs. 140, 147, 159; mtvp) without median notch; anterior metaventral process absent. Metanepisterna and metepimera narrow. Metafurca with short stalk and divergent lateral furcal arms ( Figs. 139, 147, 158; lmfa). FIGURES 129–133.Morphology of Sciacharoides thompsoni(Franz) comb. n.Head in ventral view (129), distal part of labium in ventral view (130), labrum in dorsal view (131), right mandible in dorsal view (132), and left maxilla in ventral view (133). Abbreviations: bst, basistipes; cd, cardo; fo, foramen occipitale; gal, galea; gp, gular plate; gs, gular suture; hr, hypostomal ridge; lg, ligula; lp, labial palpus; lp1–2, labial palpomere 1–2; md, mandible; mn, mentum; mst, mediostipes; mxp, maxillary palpus; mxp1–4, maxillary palpomere 1–4; occ, occipital constriction; ppf, palpifer; pst, prostheca; ptp, posterior tentorial pit; smn, submentum. Elytra ( Figs. 136, 155, 160–163) oval, each with two rudiments of asetose basal foveae ( Figs. 136, 155; bef) not connected by groove; humeral denticles and subhumeral lines absent. Hindwings well-developed, about twice as long as elytra. Legs ( Figs. 160–163) long and slender; procoxae subglobose, mesocoxae oval, metacoxae strongly transverse; all trochanters short; all femora moderately strongly clavate; tibiae and tarsi long and slender. Aedeagus ( Figs. 168–173) elongate and lightly sclerotized, thin-walled, with symmetrical median lobe and symmetrical assemblage of internal sclerites containing H-shaped subapical median structures and often with bunches of long hair-like structures on surface of internal sac; parameres free and slender, with apical setae.
Etymology.The name Sciacharoidesis derived from Sciacharis, to underline similarities between these taxa. Gender masculine. Composition and distribution.Four species of Sciacharoidesare known from the easternmost part of Australia(Queensland and New South Wales) ( Fig. 197). The genus may be broader distributed, but some species might have been misplaced in other genera, e.g. Sciacharisor Euconnus.
Remarks. Sciacharoidesdiffers from Sciacharisin the following characters: the sublateral pronotal carinae absent (present in Sciacharis); the mesoventral process developed only in front of mesocoxal cavities (extending between mesocoxal cavities in Sciacharis) and in consequence the mesocoxae not separated (clearly separated by mesoventral intercoxal process in Sciacharis); and the basal elytral foveae rudimentary (well-developed in Sciacharis). Species of Sciacharoidesare also stouter and more convex than Sciacharis. It is possible that other species from Australia, New Zealandand New Caledoniaplaced by Franz in Sciacharismay in fact belong to Sciacharoides; all members of this complex require a comprehensive revision. Among Australian Cyrtoscydminionly Palaeoscydmaenushas the mesocoxae contiguous and not separated by mesoventral process ( Jałoszyński 2012c), but this genus has lateral sutures of submentum, open procoxal sockets, asetose impressions of mesoventrite, lacks thick bristles on the head and prothorax, and lacks basal elytral foveae. Species included hereby in Sciacharoidesshow minorbut intriguing differences in the antebasal sculpture of the pronotum, length of hypostomal ridges, and in the general body shape. These differences may in future be used to subdivide Sciacharoidesinto subgenera; currently too few species are known to draw conclusions about their possible relationships. Some species described from Australiaand New Zealandunder Sciacharis(or its junior synonyms) may in fact belong to Sciacharoides. For instance, aedeagi illustrated by Franz (1975)for Euconnus( Allomaoria) parvicollis( Lea, 1914), E. quinarius Franz, 1975, E. relatus( Broun, 1893b)(all currently in Sciacharis s. str.) seem to contain structures of the internal sac similar to those of Sciacharoides, including the H-shaped sclerite. For this reason only four species previously misplaced in Horaeomorphusare revised here, and although several other, presumably undescribed species, are known to the author, they will be treated separately, when all Australian species of Sciacharishave been verified (Jałoszyński, in preparation).