Checklist of the Clubiona japonica-group spiders, with the description of a new species from China (Araneae, Clubionidae).
ABSTRACT: In the present paper, a worldwide checklist of Clubiona japonica-group spiders is provided based on published literature and authors' collections. A new japonica-group species, Clubiona grucollarissp. n. (??) from Guizhou Province and Hainan Island of China is diagnosed, described, and illustrated. A distribution map of this species is given.
Project description:Background:Clubiona milingae Barrion-Dupo, Barrion & Heong, 2013 was described from a single male and no additional specimens have been recorded. The original description was brief and the illustrations were inadequate. New information:Clubiona milingae is redescribed and illustrated based on new material from the type locality and the new distribution region (Jianfeng Mountains and Limu Mountains of Hainan Island, China). The female is reported for the first time.
Project description:Two new genera of the spider family Theridiosomatidae, Alariagen.n. with the type species Alaria chengguanensissp. n., Mengluniagen.n. with the type species Menglunia inaffectasp. n., are described from Guizhou and Yunnan, China. Nine more new species from Guangxi, Guizhou, Hainan and Yunnan Provinces of southern China are described: Baalzebub rastrariussp. n.,Baalzebub youyiensissp. n., Karstia nitidasp. n., Karstia prolatasp. n.,Ogulnius hapalussp. n., Theridiosoma plumariasp. n., Theridiosoma triumphalissp. n., Theridiosoma vimineumsp. n., Zoma fasciasp. n. The type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences in Beijing.
Project description:The present paper describes two Clubiona obesa-group species: Clubiona bicuspidata sp. n. and the male Clubiona kropfi Zhang, Zhu & Song, 2003, which is described for the first time.
Project description:Spiders (Araneae) form abundant and diverse assemblages in agroecosystems such as fruit orchards, and thus might have an important role as natural enemies of orchard pests. Although spiders are polyphagous and opportunistic predators in general, limited information exists on their natural prey at both species and community levels. Thus, the aim of this study was to assess the natural prey (realized trophic niche) of arboreal hunting spiders, their role in trophic webs and their biological control potential with direct observation of predation events in apple orchards. Hunting spiders with prey in their chelicerae were collected in the canopy of apple trees in organic apple orchards in Hungary during the growing seasons between 2013 and 2019 and both spiders and their prey were identified and measured. Among others, the composition of the actual (captured by spiders) and the potential (available in the canopy) prey was compared, trophic niche and food web metrics were calculated, and some morphological, dimensional data of the spider-prey pairs were analyzed. Species-specific differences in prey composition or pest control ability were also discussed. By analyzing a total of 878 prey items captured by spiders, we concluded that arboreal hunting spiders forage selectively and consume a large number of apple pests; however, spiders' beneficial effects are greatly reduced by their high levels of intraguild predation and by a propensity to switch from pests to alternative prey. In this study, arboreal hunting spiders showed negative selectivity for pests, no selectivity for natural enemies and positive selectivity for neutral species. In the trophic web, the dominant hunting spider taxa/groups (Carrhotus xanthogramma, Philodromus cespitum, Clubiona spp., Ebrechtella tricuspidata, Xysticus spp. and 'Other salticids') exhibit different levels of predation on different prey groups and the trophic web's structure changes depending on the time of year. Hunting spiders show a high functional redundancy in their predation, but contrary to their polyphagous nature, the examined spider taxa showed differences in their natural diet, exhibited a certain degree of prey specialization and selected prey by size and taxonomic identity. Guilds (such as stalkers, ambushers and foliage runners) did not consistently predict either prey composition or predation selectivity of arboreal hunting spider species. From the economic standpoint, Ph. cespitum and Clubiona spp. were found to be the most effective natural enemies of apple pests, especially of aphids. Finally, the trophic niche width of C. xanthogramma and Ph. cespitum increased during ontogeny, resulting in a shift in their predation. These results demonstrate how specific generalist predators can differ from each other in aspects of their predation ecology even within a relatively narrow taxonomic group.
Project description:BACKGROUND: The evolution and origin of cave organisms is a recurring issue in evolutionary studies, but analyses are often hindered by the inaccessibility of caves, morphological convergence, and complex colonization processes. Here we investigated the evolutionary history of Nesticella cave spiders, which are mainly distributed in the Yunnan-Guizhou Plateau, China. With comprehensive sampling and phylogenetic and coalescent-based analyses, we investigated the tempo and mode of diversification and the origins of these troglobites. We also aimed to determine which factors have influenced the diversification of this little-known group. RESULTS: Coalescent-based species delimitation validated the 18 species recognized by morphological inspection and also suggested the existence of cryptic lineages. Divergence time estimates suggested that Nesticella cave spiders in the Yunnan-Guizhou Plateau constituted a monophyletic troglobite clade that originated in the middle Miocene (11.1-18.6 Ma). Although the Yunnan-Guizhou Plateau clade was composed exclusively of troglobite species, suggesting an ancient common subterranean ancestor, we favor multiple, independent cave colonizations during the Pleistocene over a single ancient cave colonization event to explain the origin of these cave faunas. The diversification of plateau Nesticella has been greatly influenced by the sequential uplift of the plateau and likely reflects multiple cave colonizations over time by epigean ancestors during Pleistocene glacial advances. CONCLUSIONS: We concluded that plateau cave Nesticella represent an ancient group of spiders, but with young troglobite lineages that invaded caves only recently. The absence of extant epigean relatives and nearly complete isolation among caves supported their relict status. Our work highlights the importance of comprehensive sampling for studies of subterranean diversity and the evolution of cave organisms. The existence of potentially cryptic species and the relict status of Nesticella highlight the need to conserve these cave spiders.
Project description:Pristidia cervicornuta Yu, Zhang & Chen, 2017 is redescribed based on new material from the type locality, Diaoluo Mountains of Hainan Island, China. The female is described and illustrated for the first time. In addition, this paper further illustrates the male, and provides a supplementary description.
Project description:Spiders represent one of the most studied arachnid orders. They are particularly intriguing from a cytogenetic point of view, due to their complex and dynamic sex chromosome determination systems. Despite intensive research on this group, cytogenetic data from African spiders are still mostly lacking. In this study, we describe the karyotypes of 38 species of spiders belonging to 16 entelegyne families from South Africa and Namibia. In the majority of analysed families, the observed chromosome numbers and morphology (mainly acrocentric) did not deviate from the family-level cytogenetic characteristics based on material from other continents: Tetragnathidae (2n? = 24), Ctenidae and Oxyopidae (2n? = 28), Sparassidae (2n? = 42), Gnaphosidae, Trachelidae and Trochanteriidae (2n? = 22), and Salticidae (2n? = 28). On the other hand, we identified interspecific variability within Hersiliidae (2n? = 33 and 35), Oecobiidae (2n? = 19 and 25), Selenopidae (2n? = 26 and 29) and Theridiidae (2n? = 21 and 22). We examined the karyotypes of Ammoxenidae and Gallieniellidae for the first time. Their diploid counts (2n? = 22) correspond to the superfamily Gnaphosoidea and support their placement in this lineage. On the other hand, the karyotypes of Prodidominae (2n? = 28 and 29) contrast with all other Gnaphosoidea. Similarly, the unusually high diploid number in Borboropactus sp. (2n? = 28) within the otherwise cytogenetically uniform family Thomisidae (mainly 2n? = 21-24) supports molecular data suggesting a basal position of the genus in the family. The implementation of FISH methods for visualisation of rDNA clusters facilitated the detection of complex dynamics of numbers of these loci. We identified up to five loci of the 18S rDNA clusters in our samples. Three different sex chromosome systems (X0, X1X20 and X1X2X30) were also detected among the studied taxa.
Project description:Bilateral asymmetry in the genitalia is a rare but widely dispersed phenomenon in the animal tree of life. In arthropods, occurrences vary greatly from one group to another and there seems to be no common explanation for all the independent origins. In spiders, genital asymmetry appears to be especially rare. Most known species show almost perfectly symmetrical genitals with the right and left sides being mirror images of each other. However, some examples of asymmetric genitalia have been studied and many other reports are scattered in the taxonomic literature. Based on a broad literature survey, we found several species in thirteen families with evidence of genital asymmetry, mostly expressed only in females. Our review suggests that spider genital asymmetries, although rare, are more common than previously thought and taxonomic descriptions and illustrations are a useful but not entirely reliable tool for studying them. Here we also report on directional asymmetry in the liocranid spider Teutamus politus, the first known case of morphologically asymmetric male genitals in Entelegynae spiders. Generalities, evolution and categorization of asymmetry in spiders are further discussed.
Project description:AbstractClubiona Latreille, 1804, with more than 500 named species, is one of the largest genera of Araneae. The genus has 15 synonyms, most of which are not listed in the World Spider Catalog (2018) and unknown to many arachnologists. The most comprehensive survey of Clubiona sensu lato by Wunderlich (2011) also lacked a few synonyms. In this paper all genus group names described in Clubiona are listed with their type species. Most of these names correspond to the species groups recognised in Clubiona sensu lato. We agree that Porrhoclubiona Lohmander, 1944 (= Clubionagenevensis-group) deserves a status of a separate genus and provide the diagnosis of this taxon. Three species of Porrhoclubiona that occur in Central Asia are surveyed, and two of them are described as new to science: P.laudata (O. Pickard-Cambridge, 1885), comb. n. (??, Xinjiang, Tibet, China), P.bosmansisp. n. (??, Tajikistan), and P.moradmandisp. n. (??, Fars, Iran). It seems that all records of P.genevensis L. Koch, 1866 from China refer to P.laudata. The records of Clubionavegeta Simon, 1918 from Tajikistan and Iran refer to P.bosmansi sp. n. and P.moradmandi sp. n., respectively. The following new combinations have been established: Porrhoclubionadecora (Blackwall, 1859), comb. n., P.diniensis (Simon, 1878), comb. n., P.leucaspis (Simon, 1932), comb. n., P.minor (Wunderlich, 1987), comb. n., P.pseudominor (Wunderlich, 1987), comb. n., P.pteronetoides (Deeleman-Reinhold, 2001), comb. n., P.vegeta (Simon, 1918), comb. n., P.viridula (Ono, 1989), comb. n., and P.wunderlichi (Mikhailov 1992), comb. n. (all ex. Clubiona). SEM study of the structure considered earlier as scopula in Clubiona and Porrhoclubiona reveals that it is represented by several lateral rows of movable macrosetae (spines) with a locking mechanism.
Project description:Abstract Seven new species of jumping spiders collected from Xishuangbanna Tropical Botanical Garden in Yunnan, China, are diagnosed and described: Charippusyinaesp. nov. (??), Chinattusinflatussp. nov. (?), Indomarengoyuisp. nov. (?), Phintellabannasp. nov. (??), P.miisp. nov. (??), Simaethamenglunsp. nov. (??) and S.pengisp. nov. (??). Charippusyinaesp. nov. is the second species of the genus Charippus Thorell, 1895, which was previously known only from one sex.