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1.
This phylogenetic analysis of 31 exemplar taxa treats the 12 families of Araneoidea (Anapidae, Araneidae, Cyatholipidae, Linyphiidae, Mysmenidae, Nesticidae, Pimoidae, Symphytognathidae, Synotaxidae, Tetragnathidae, Theridiidae, and Theridiosomatidae). The data set comprises 93 characters: 23 from male genitalia, 3 from female genitalia, 18 from cephalothorax morphology, 6 from abdomen morphology, 14 from limb morphology, 15 from the spinnerets, and 14 from web architecture and other behaviour. Criteria for tree choice were minimum length parsimony and parsimony under implied weights. The outgroup for Araneoidea is Deinopoidea (Deinopidae and Uloboridae). The preferred shortest tree specifies the relationships ((Uloboridae, Deinopidae) (Araneidae (Tetragnathidae ((Theridiosomatidae (Mysmenidae (Symphytognathidae, Anapidae))) ((Linyphiidae, Pimoidae) ((Theridiidae, Nesticidae) (Cyatholipidae, Synotaxidae))))))). The monophyly of Tetragnathidae (including metines and nephilines), the symphytognathoids, theridiid-nesticid lineage, and Synotaxidae are confirmed. Cyatholipidae are sister to Synotaxidae, not closely related to either the Araneidae or Linyphiidae, as previously suggested. Four new clades are proposed: the cyatholipoids (Cyatholipidae plus Synotaxidae), the 'spineless femur clade' (theridioid lineage plus cyatholipoids), the 'araneoid sheet web builders' (linyphioids plus the spineless femur clade), and the 'reduced piriform clade' (symphytognathoids plus araneoid sheet web builders). The results imply a coherent scenario for web evolution in which the monophyletic orb gives rise to the monophyletic araneoid sheet, which in turn gives rise to the gumfoot web of the theridiid-nesticid lineage. While the spinning complement of single pairs of glands does not change much over the evolution of the group, multiple sets of glands are dramatically reduced in number, implying that derived araneoids are incapable of spinning many silk fibers at the same time.  相似文献   

2.
The spider genus Nanoa gen. nov. (Araneae, Pimoidae) is described to place Nanoa enana , a new species of pimoids from Western North America. Parsimony analysis of morphological characters provides support for the monophyly of Pimoa plus Nanoa and corroborates the monophyly of Pimoidae and of the clade Linyphiidae plus Pimoidae. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 145 , 249–262.  相似文献   

3.
This paper offers the first cladistic analysis of a wide selection of theridiid genera based on morphological data. The analysis treats 53 theridiid taxa representing 32 genera (Achaearanea, Anelosimus, Ameridion, Argyrodes, Ariamnes, Carniella, Cerocida, Chrysso, Coleosoma, Dipoena, Emertonella, Enoplognatha, Episinus, Euryopis, Faiditus, Kochiura, Latrodectus, Neospintharus, Nesticodes, Pholcomma, Phoroncidia, Rhomphaea, Robertus, Selkirkiella, Spintharus, Steatoda, Stemmops, Theridion, Theridula, Thymoites, Thwaitesia, Tidarren) and eight outgroup taxa representing the families Nesticidae (Eidmanella and Nesticus), Synotaxidae (Synotaxus, two species), Pimoidae (Pimoa), Linyphiidae (Linyphia), Tetragnathidae (Tetragnatha) and Araneidae (Argiope). The parsimony analysis of 242 morphological and behavioural characters found a single, most parsimonious tree. The monophyly of theridiids and their sister relationship with nesticids is strongly supported. The recent resurrection of Ariamnes and Rhomphaea from Argyrodes made the latter paraphyletic. However, Ariamnes and Rhomphaea are characterized by an array of characters, and Argyrodes still contains dramatically distinct clades for which names are available: Faiditus (removed from synonymy ? RS) and Neospintharus (RS). These revalidations provide a classification with greater information content and utility. These three genera, along with Ariamnes, Rhomphaea and Spheropistha, comprise the subfamily Argyrodinae. The monophyly and composition of the subfamilies Hadrotarsinae, Spintharinae, Pholcommatinae, Latrodectinae and Theridiinae are discussed. Theridion is paraphyletic and in need of revision. Anelosimus as currently circumscribed is paraphyletic, a problem resolved by revalidating Selkirkiella (RS) and Kochiura (RS). Numerous new combinations are established. The results suggest the monophyletic origin of both kleptoparasitism and araneophagy in the lineage leading to Argyrodinae, negating hypotheses that either arose from the other. Sociality evolved multiple times within the family, accounting for as much as one fourth of the origins of social behaviour among all spiders. No losses of sociality are implied. The hypothesis of maternal care as the pathway to sociality receives support. Evolution of theridiid webs is complex, with multiple modifications and loss of the basic theridiid cobweb. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 141 , 447–626.  相似文献   

4.
In this paper we carry out a taxonomic revision and phylogenetic analysis of the linyphiid spider genus Solenysa Simon, 1894. A total of 12 species is treated here, including five new species collected from China and Japan: Solenysa akihisai Tu sp. nov., Solenysa lanyuensis Tu sp. nov., Solenysa retractilis Tu sp. nov., Solenysa tianmushana Tu sp. nov. , and Solenysa yangmingshana Tu sp. nov. Solenysa circularis Gao, Zhu & Sha, 1993 is a junior synonym of Solenysa protrudens Gao, Zhu & Sha, 1993. We have assembled two different character matrices to reconstruct the phylogenetic relationships of Solenysa. In the first matrix (Matrix 1), five representative species of Solenysa were added to the morphological dataset of Miller & Hormiga to test the monophyly of the genus and its placement within Linyphiidae. The genitalic structures and somatic morphology of Solenysa were studied by means of scanning electron microscopy for the first time. To infer the species‐level phylogenetic relationships of Solenysa we produced a second matrix (Matrix 2) that includes all 12 Solenysa species and six outgroup species chosen from the results of the analysis of the first matrix. The two most parsimonious trees from the analysis of Matrix 1 support the monophyly of Solenysa and its placement within the ‘Distal Erigonines’ clade. The single most parsimonious tree resulting from the analysis of the second matrix suggests that the Solenysa clade includes four monophyletic groups, each group represented by a distinct genitalic pattern. The morphology of Solenysa, both somatic and genitalic, is highly autapomorphic. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 484–530.  相似文献   

5.
The spider genus Weintrauboa new genus (Araneae, Pimoidae) is described to place two species of pimoids from Japan and adjacent islands that were formerly classified in the linyphiid genus Labulla . Weintrauboa contortipes (Karsch) new comb., the type species, and W. chikunii (Oi) new comb. are redescribed. Parsimony analysis of morphological characters provides robust support for the monophyly of the genus Weintrauboa and corroborates the monophyly of Pimoa , Pimoidae, and the clade Linyphiidae plus Pimoidae. New diagnoses for Pimoa and Pimoidae are provided.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 261–281  相似文献   

6.
This study infers the higher-level cladistic relationships of linyphiid spiders from five genes (mitochondrial CO1, 16S; nuclear 28S, 18S, histone H3) and morphological data. In total, the character matrix includes 47 taxa: 35 linyphiids representing the currently used subfamilies of Linyphiidae (Stemonyphantinae, Mynogleninae, Erigoninae, and Linyphiinae (Micronetini plus Linyphiini)) and 12 outgroup species representing nine araneoid families (Pimoidae, Theridiidae, Nesticidae, Synotaxidae, Cyatholipidae, Mysmenidae, Theridiosomatidae, Tetragnathidae, and Araneidae). The morphological characters include those used in recent studies of linyphiid phylogenetics, covering both genitalic and somatic morphology. Different sequence alignments and analytical methods produce different cladistic hypotheses. Lack of congruence among different analyses is, in part, due to the shifting placement of Labulla , Pityohyphantes , Notholepthyphantes , and Pocobletus . Almost all combined analyses agree on the monophyly of linyphioids, Pimoidae, Linyphiidae, Erigoninae, Mynogleninae, as well as Stemonyphantes as a basal lineage within Linyphiidae. Our results suggest independent origins of the desmitracheate tracheal system in micronetines and erigonines, and that erigonines were primitively haplotracheate. Cephalothoracic glandular specializations of erigonines and mynoglenines apparently evolved independently. Subocular sulci of mynoglenines and lateral sulci (e.g. Bathyphantes ) evolved independently but glandular pores in the prosoma proliferated once. The contribution of different character partitions and their sensitivity to changes in traditional analytical parameters is explored and quantified.
 © The Willi Hennig Society 2009.  相似文献   

7.
Eight new genera and 30 new species are described: Cirrosus gen. n. (type species Cirrosus atrocaudatus sp. n. (♂♀)), Conglin gen. n. (type species Conglin personatus sp. n. (♀)), Curtimeticus gen. n. (type species Curtimeticus nebulosus sp. n. (♂)), Gladiata gen. n. (type species Gladiata fengli sp. n. (♂)), Glebala gen. n. (type species Glebala aspera sp. n. (♂)), Glomerosus gen. n. (type species Glomerosus lateralis sp. n. (♂)), Smerasia gen. n. (type species Smerasia obscurus sp. n. (♂♀)), Vittatus gen. n. (type species Vittatus fencha sp. n. (♂♀)); Batueta cuspidata sp. n. (♂♀), Capsulia laciniosa sp. n. (♂), Dactylopisthes separatus sp. n. (♀), Gongylidiellum bracteatum sp. n. (♀), Houshenzinus xiaolongha sp. n. (♂♀), Laogone bai sp. n. (♂), Laogone lunata sp. n. (♂♀), Maro bulbosus sp. n. (♀), Nasoonaria circinata sp. n. (♂♀), Neriene circifolia sp. n. (♂♀), Oedothorax biantu sp. n. (♀), Oilinyphia hengji sp. n. (♂♀), Paikiniana furcata sp. n. (♂♀), Parameioneta bishou sp. n. (♂♀), Parameioneta multifida sp. n. (♂♀), Parameioneta tricolorata sp. n. (♂♀), Tapinopa undata sp. n. (♂), Theoa bidentata sp. n. (♂♀), Theoa vesica sp. n. (♂♀), Vittatus bian sp. n. (♂♀), Vittatus latus sp. n. (♂♀), Vittatus pan sp. n. (♂♀). The male of Kaestneria bicultrata Chen & Yin, 2000 and the females of Asiagone perforata Tanasevitch, 2014 and Batueta similis Wunderlich & Song, 1995 are described for the first time; photos of Bathyphantes paracymbialis Tanasevitch, 2014 are provided.  相似文献   

8.
The genus Labulla Simon is circumscribed in phylogenetic terms to include the species Labulla thoracica (Wider), L. flahaulti Simon and L. machadoi sp. nov. The genital anatomy of the genus is described in detail and the taxonomy of the genus is reviewed. The monophyly of Labulla is supported by numerous morphological apomorphies of the male palp and female epigynum. Based on a cladistic analysis, a new genus, Pecado gen. nov. , is erected to place Labulla impudica Denis, from Northern Africa. Lepthyphantes insularis Saito and ' Labulla ' nepula Tikader, both formerly included in Labulla , are not congeneric with the type species of Labulla .  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 359–404.  相似文献   

9.
Current knowledge of “micronetine” female genitalia is almost exclusively based on transmitted light microscopy data. As such, our understanding of the epigynal anatomy is incomplete and somewhat misleading, to the extent that it hinders comparative studies of linyphiid diversity. We used scanning electronic microscopy (SEM) to study the complex epigynal morphology of “micronetine” spiders. Enzymatic digestion of soft tissues allowed us to examine the internal chitinized structures in detail using SEM. A taxonomic sample of nine species was selected to represent the morphological genitalic diversity of female “micronetines” (including one member of the Erigoninae clade). Results reveal that the epigynum consists of a pair of grooves formed by integument folds (copulatory and fertilization grooves). The protruding epigynal region is divided into a ventral and a dorsal plate by the grooves; both plates can be modified to form an epigynal cavity and/or a scape. Our observations confirm the widespread occurrence of epigynal grooves, rather than ducts, in “micronetines”. Epigynal grooves seem to be common in linyphioids and other spider groups.  相似文献   

10.
11.
A cladistic analysis was applied to test the monophyly of the genus Isoctenus. The data matrix comprised 28 taxa scored for 53 morphological and two behavioural characters. The analysis resulted in two equally parsimonious trees of 89 steps. The strict consensus was used to discuss the relationships of Isoctenus and related Cteninae genera. Ctenopsis Schmidt is synonymized with Isoctenus. Isoctenus foliifer Bertkau, I. strandi Mello‐Leitão, I. eupalaestrus Mello‐Leitão, I. janeirus (Walckenaer), I. coxalis (Pickard‐Cambridge), I. corymbus Polotow, Brescovit & Pellegatti‐Franco and I. malabaris Polotow, Brescovit & Ott are maintained in Isoctenus. Four species currently included in Ctenus are transferred to Isoctenus: I. griseolus (Mello‐Leitão) comb. nov., I. taperae (Mello‐Leitão) comb. nov., I. herteli (Mello‐Leitão) comb. nov. and I. minusculus (Keyserling) comb. nov. The following specific names are synonymized: Ctenus sanguineus Walckenaer, C. semiornatus Mello‐Leitão and Ctenopsis stellata Schmidt with Isoctenus janeirus (Walckenaer), Ctenus mourei Mello‐Leitão with Isoctenus herteli (Mello‐Leitão) and Ctenus pauper Mello‐Leitão with Isoctenus strandi Mello‐Leitão. Isoctenus sigma Schenkel, described from French Guiana, is transferred to Ctenus. Four species are newly described: Isoctenus areia sp. nov. from Paraíba, Brazil, I. charada sp. nov. and I. segredo sp. nov. from Paraná, Brazil, and I. ordinario sp. nov. from south and south‐eastern Brazil and north‐eastern Argentina. Isoctenus latevittatus Caporiacco is considered species inquirenda. Parabatinga gen. nov. is proposed to include Ctenus brevipes Keyserling. The following synonymies are established: Ctenus taeniatus Keyserling, C. tatarandensis Tullgren, C. anisitsi Strand, C. atrivulvus Strand, C. mentor Strand, C. brevipes brevilabris Strand, Isoctenus masculus Mello‐Leitão and Ctenus birabeni Mello‐Leitão with Parabatinga brevipes (Keyserling) comb. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 583–614.  相似文献   

12.
13.
14.
The European sheet-web spider Linyphia triangularis (Araneae: Linyphiidae) has become established in Maine, where it often reaches very high densities. Two lines of evidence from previous work suggest that L. triangularis affects populations of the native linyphiid spider Frontinella communis. First, F. communis individuals are relatively scarce in both forest and coastal habitat where L. triangularis is common, but more common where L. triangularis is at low density. Second, in field experiments, F. communis species are less likely to settle in experimental plots when L. triangularis is present, and F. communis disappears from study plots when L. triangularis is introduced. Here we test two mechanisms that may underlie these patterns. First, we tested whether L. triangularis invades and usurps the webs of F. communis. When spiders were released onto webs of heterospecifics, L. triangularis was more likely to take over or share webs of F. communis than the reverse. We also observed natural takeovers of F. communis webs. Second, we explored the hypothesis that L. triangularis reduces prey availability for native species. We sampled flying prey in areas with L. triangularis and those where it had been removed, and found no effect of spider presence on measured prey density. We also found no effect of prey supplementation on web tenacity in F. communis, suggesting that F. communis movements are not highly dependent on prey availability. We conclude that web takeover is likely more important than prey reduction in driving negative effects of L. triangularis on F. communis.  相似文献   

15.
An endemic group of Malagasy spiders (Araneae: Archaeidae: Eriauchenius ) called the gracilicollis group is revised. The monophyly and phylogenetic relationships of the gracilicollis group are tested based on morphological characters. Archaeid spiders of Madagascar have evolved varying degrees of elongation in the cephalic area. Historically, it was believed that the extremely elongated cephalic area had evolved only once. These morphological data support the monophyly of the gracilicollis group and suggest that the elongated cephalic area has evolved more than once. All 14 species from the gracilicollis group are described and keyed, of which nine are new species: Eriauchenius ambre sp. nov. , Eriauchenius anabohazo sp. nov. , Eriauchenius borimontsina sp. nov. , Eriauchenius griswoldi sp. nov. , Eriauchenius halambohitra sp. nov. , Eriauchenius lavatenda sp. nov. , Eriauchenius namoroka sp. nov. , Eriauchenius spiceri sp. nov. and Eriauchenius voronakely sp. nov . The morphology of the gracilicollis group is examined in detail and figures of the male and female genitalia are presented. The distributions of the gracilicollis group species are presented and discussed and higher species group relationships within the Archaeidae are discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 255–296.  相似文献   

16.
Spiders are important predators in terrestrial ecosystems, yet we know very little about the principal feeding structures of spiders, the chelicerae, which are functionally equivalent to “jaws” or “mandibles” and are an extremely important aspect of spider biology. In particular, members of Palpimanoidea have evolved highly unusual cheliceral morphologies and functions, including high-speed, ballistic movements in mecysmaucheniid spiders, the fastest arachnid movements known thus far, and the elongated, highly maneuverable chelicerae of archaeids that use an attack-at-a-distance strategy. Here, using micro-Computed-Tomography scanning techniques, we perform a comparative study to examine cheliceral muscle morphology in six different spider specimens representing five palpimanoid families. We provide a hypothesis for homology in palpimanoid cheliceral muscles and then compare and contrast these findings with previous studies on other non-palpimanoid spiders. We document and discuss two sets of cheliceral muscles in palpimanoids that have not been previously observed in other spiders or which may represent a position shift compared to other spiders. In the palpimanoids, Palpimanus sp., Huttonia sp., and Colopea sp. showed similar cheliceral muscle anatomy. In Eriauchenius ranavalona, which has highly maneuverable chelicerae, some of the muscles have a more horizontal orientation, and there is a greater degree of cheliceral muscle divergence. In Zearchaea sp. and Aotearoa magna, some muscles have also shifted to a more horizontal orientation, and in Zearchaea sp., a species with a ballistic, high-speed predatory strike, there is a loss of cheliceral muscles. This research is a first step toward understanding cheliceral form and function across spiders.  相似文献   

17.
Ricefishes, known best by the model organism, the medaka, Oryzias latipes Temminck & Schlegel, 1846, comprise the family Adrianichthyidae, which ranges broadly throughout fresh and brackish waters of Central, South and Southeast Asia and the Indo‐Malay‐Philippines Archipelago as far east as Timor. Twenty‐eight Recent species are recognized here in two monophyletic genera, Adrianichthys and Oryzias. Xenopoecilus and Horaichthys are placed in synonymy of Oryzias for the first time. Adrianichthys comprises four species from Lake Poso, Sulawesi, Indonesia. Oryzias comprises 24 species that live throughout the range of the family. A fossil genus and species, ?Lithopoecilus brouweri from the Miocene of central Sulawesi, is included tentatively in the Adrianichthyidae. Evidence for the sister group relationship of adrianichthyids and exocoetoids is reviewed briefly and that relationship corroborated. Monophyly of adrianichthyids is likewise strongly supported here. Species groups within Oryzias are diagnosed as monophyletic largely based on osteology, colour pattern and meristic variation. They correspond only in part to species groups previously recognized based on chromosome constitution. Miniature species do not comprise a monophyletic group; disjunct absolute size in close relatives has evolved repeatedly. Oryzias latipes is a member of a species complex that includes O. luzonensis, O. curvinotus and the miniatures O. sinensis and O. mekongensis. A new species, Oryzias bonneorum sp. nov. , is described from Lake Lindu, Sulawesi, Indonesia. Lectotypes are designated for Haplochilus celebensis Weber, 1894 and Haplochilus timorensis Weber & de Beaufort, 1922. No claim to original US Government works. Journal compilation © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 494–610.  相似文献   

18.
Reproductive competition among males selects for a broad variety of strategies and traits from mate guarding to nuptial food gifts. Males of many dwarf spider species possess conspicuous secondary cephalic modifications, and the few studies available suggest that these cephalic structures are connected to extensive glandular tissue. Because females were observed to contact the male head structures during mating, these traits may have evolved in the context of sexual selection. We investigated the structure, glandular equipment, and sensory equipment of the cephalic regions of several species of the dwarf spider genus Oedothorax with varying degrees of sexual dimorphism using light and electron microscopy. In one Oedothorax species, there are two male morphs that exhibit a cephalic modification (O. gibbosus gibbosus) or not (O. gibbosus tuberosus). Our study demonstrates that all males investigated produce cephalic secretions, irrespective of the morphology of their cephalic region, however, they may differ in amount of secretion and in cellular organization. In males of O. apicatus, O. gibbosus gibbosus and O. retusus the gland cells are very abundant in the area of a cephalic hump, whereas in the less conspicuous O. agrestis, and O. gibbosus tuberosus the gland cells are restricted to a small area behind the ocular region or include the ocular region as in O. fuscus. The glandular tissue consists of two gland types in O. agrestis, O. fuscus, O. gibbosus tuberosus and O. retusus and of only one type in O. apicatus and O. gibbosus gibbosus. The setae present on the head structure of all species seem to function as mechano‐ and/or chemoreceptors. The implications of our findings for the evolution of secretory head structures are discussed along with their potential for driving speciation. J. Morphol. 2011. © 2011Wiley‐Liss, Inc.  相似文献   

19.
Abstract:  A mass rearing method for Erigone atra (Blackwall) (Araneae: Linyphiidae) allowing continuous laboratory rearing is described. Twenty 1–2-day old spiderlings were kept together in plastic boxes, which were filled with soil containing a culture of the Collembola species, Lepidocyrtus lanuginosus (Gmelin) (Entomobryidae), and serving the spiders as a continuous available prey source. Once per week vestigial-wing fruit flies of Drosophila melanogaster Meigen (Diptera: Drosophilidae) were provided as additional prey. In addition, the rearing boxes were filled with wood-wool serving spiders as points of contact for their webs. After 3–5 weeks most of the spiderlings developed to adults, which were separated individually into glass tubes filled with soil and Collembola until all of them became adult. To produce a new generation of spiders 20–40 adult/subadult spiders originating from different mass rearing boxes were brought together and kept and fed in the same way as the spiderlings. Within a few days females started to produce eggsacs. The eggsacs were transferred into glass tubes filled with a layer of moist plaster of Paris until the spiderlings hatched, which were then bred as described above. Erigone atra was bred over 12 generations within a period of 2 years. The mean rearing success (from 1 to 2-day-old spiderlings to adults) was 59.3%. Decreasing rearing success, decrease of fecundity or decrease of adult spider size were not observed. Advantages and use of the mass rearing method are discussed in relation to rearing methods for other spiders.  相似文献   

20.
Distributions, endemism and diversity among East African linyphiids are analysed and discussed in relation to other forest organisms and the environmental history of eastern African. A total of 231 species are reported from eastern Africa, of which 14 are confined to the Afroalpine region and 114 species to moist forests. Only 12 of the latter are widely distributed. The rest are only known from one or two localities. Information on habitats and distributions of all species is tabulated. Few species are shared between East African mountains and there are no detectable gradients of species diversity between mountains. There is, however, a gradient of decreasing species diversity from high latitudes to the Equator. Vicariance patterns are demonstrated for Elgonia, Ophrynia and Callitrichia in the Eastern Arc Mountains, Tanzania—areas that also hold the highest degree of endemism (> 80% on individual mountains) among linyphiids. The many endemic species on nearby mountains suggest that intermontane dispersal (ballooning) is rare or non-existent. There is no evidence for a distinction between highland and lowland linyphiid faunas, but altitudinal segregation of single species is demonstrated. The question of the reality of highland and lowland faunas cannot be solved by studying the altitudinal distribution of single species. Phylogenetic relationships must be taken into consideration to determine where sister-groups/species are located (lowland or highland).  相似文献   

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