Abdidam2847

The polynoid genus Chaetacanthus Seidler, 1922 currently includes three nominal species provided with parapodial branchiae. Members of this taxon have palps with longitudinal rows of papillae, notochaetae abundant and neurochaetae spinulose. Most Chaetacanthus species were originally described as belonging to Lepidonotus Leach, 1816, and some of them were later regarded as subjective synonyms of Iphione magnifica Grube, 1876, the type species for Chaetacanthus. This species was described from the Caribbean Sea and later recorded for the tropical Eastern Pacific. After the supposed Amphi-American distribution, a revision of all available material was performed in order to clarify the generic delineation, and to improve the understanding of species systematics. Further, some non-type specimens collected in Panama allowed us to have a better understanding of the variation of elytral shape and ornamentation along the body. The type material of Polynoe brasiliensis de Quatrefages, 1866 was examined and despite its poor condition, it shows parapodial branchial filaments which were overlooked in the original description; these branchiae are also present in the holotype of I. magnifica. We identify that there are no relevant difference between both species, and they are regarded as synonyms, and Chaetacanthus brasiliensis (de Quatrefages, 1866) is newly combined and is the senior synonym. On the other hand, Chaetacanthus pilosus (Treadwell, 1937), from the Eastern Pacific, and C. pomareae (Kinberg, 1856) from the South Central Pacific are redescribed, and C. harrisae n. sp., and C. ornatus n. sp. are both newly described from the Eastern Pacific. A key to identify all species of Chaetacanthus of the World, together with an appendix for the reversal of precedence of Lepidonotus Leach, 1816 over Eumolpe Oken, 1807 are also included.New species, Frenopyxis stierlitzi, is described from tree hollows in the urban parks in Moscow (Russia) and Potsdam (Germany). The species belongs to the new genus of the family Centropyxidae and characterized by unique character, i.e. an internal thick organic lip surrounding an aperture and continuing in a bridle, which connects an aperture with the internal side of a shell wall and broaden in the place of connection of a bridle and a shell wall. The systematics of the family Centropyxidae is discussed and the importance of the structures, which divide inner shell volume into compartments, is underlined.Chalcis Fabricius (Hymenoptera Chalcididae) currently includes over 50 described species, most of them from temperate regions of the Northern Hemisphere. Prior to the present study, only Chalcis pilicauda (Cameron) had been recorded from South America. The examination of specimens collected in Argentina, southern Bolivia, Brazil, Ecuador, Paraguay, and Uruguay allowed the description of six new species C. boi Saguiah Tavares sp. nov., C. danunciae Saguiah Tavares sp. nov., C. intervalensis Saguiah Tavares sp. nov., C. periotoi Saguiah Tavares sp. nov., C. quechua Saguiah Tavares sp. nov., and C. winstonae Saguiah Tavares sp. nov. Chalcis pilicauda is redescribed, and C. ornatifrons (Cameron) stat. rev. is removed from synonym under C. pilicauda and re-established. An identification key for South American species is presented.Two new species of Maera Leach, 1814 and Quadrimaera Krapp-Schickel Ruffo, 2000 included in the Maera-clade are described from Japan. Maera denticoxa sp. nov. was collected from Iwate and Hokkaido Prefectures and can be distinguished from its congeners by the small notches on the posteroventral margins of coxae 1-6. Quadrimaera angulata sp. nov. from north of Tanegashima Island in Kagoshima Prefecture is characterized by the distal tooth on the mandibular palp article 1, the rounded palm of the female gnathopod 2, and the angular posterodistal margin of the pereopod 7 basis. Keys to Japanese species of the Maera-clade are provided. In total, seventeen species included in the clade occur in Japan.The genus Biapertura Smirnov, 1971, with type species B. affinis (= Lynceus affinis Leydig, 1860) is re-evaluated, removing the affinis-group from polyphyletic Alona s. lato. Biapertura s. str. is a taxon which could be defined by large size (up to 1.1 mm), having head shield with triangular posterior portion and two connected major head pores, and by having massive postabdomen with over 10 well-developed composite marginal denticles and well-developed lateral fascicles of setulae. Thoracic limbs of Biapertura are of Hexalona-type, inner distal lobe of limb I bear extremely large, usually claw-like seta 1. Australian species of the genus, B. kendallensis (Henry, 1919) and B. elliptica (Sinev, 1997), are fully redescribed here. Morphological analysis suggests that Biapertura s. str. check details is a sister-group to Alona s. str. A key to seven species of the genus is provided and a discussion of their geographic distribution and habitat type is given.The Cyana dohertyi (Elwes, 1890) species-group was erected by Volynkin et al. (2017) and characterized in details by Volynkin et al. (2019). The group is most diverse in mainland China and northern Indochina and comprises 16 valid species and two subspecies (Volynkin et al. 2019; Singh et al. 2020). During a lepidopterological expedition to the northwestern part of China's Sichuan Province in June and July of 2019, a series of specimens of both sexes of an unidentified Cyana species was collected. The species is closely related to Cyana abiens Fang, 1992 known from the Chinese Shaanxi and Gansu Provinces. However, the specimens collected in Sichuan and C. abiens have conspicuous external and genital differences and the Sichuan population represents another species, which is described below as new.Two species of the featherwing beetle genus Discheramocephalus Johnson are known to occur in Madagascar. One of them is known from females only, and some important morphological structures have never been described and illustrated, including details of male genitalia. Morphology of the male of D. bisulcatus Darby is illustrated and described for the first time, including the aedeagus and abdominal structures, and the male genitalia of D. vasilii Darby are also illustrated in detail for the first time. Diagnoses of both species are emended to include newly described structures.