In this study, 10 nominal species of Eustala Simon, 1895 are synonymized with other species of the genus, mostly based on matching males and females erroneously described as different species. Parawixia rimosa (Keyserling, 1892) is considered a senior synonym of Eustala decemtuberculata Caporiacco, 1955. Eustala isosceles Mello-Leitao, 1939 is transferred to Kapogea Levi, 1997 and considered a senior synonym of Kapogea alayoi (Archer, 1958) based on abdomen shape and coloration. Micrathena beta Caporiacco, 1947 is redescribed, illustrated and transferred from Linyphiidae back to Araneidae. This species can be easily distinguished from other members of the genus by the male palpus with an enlarged and modified paracymbium and a narrower hook as a conductor. Micrathena sanctispiritus Brignoli, 1983 is removed from the synonymy with M. lindenbergi Mello-Leitao, 1940 and considered a senior synonym of M. guanabara Levi, 1985.

Two new species in the genus Theridion Walckenaer 1805 (Araneae: Theridiidae) are described: T. logan, sp. nov., from Utah, USA, and T pierre, sp. nov., from South Dakota, USA. Diagnoses, descriptions and habitat notes are provided for both sexes of these new species. Both species are from open, grassland-type habitats.

The araneid genus Micropoltys Kulczyński, 1911 was originally described based on a single female specimen from western New Guinea. Three new species of the genus are reported here, M. baitetensis from eastern New Guinea, M. debakkeri from New Guinea and Cape York, and M. heatherae from north-eastern Australia and islands in the Torres Strait. No further specimens of Micropoltys placenta, the type species, have been discovered and this species is redescribed from the type female. Phylogenetic relationships of Micropoltys are briefly discussed.

The araneid genus Micropoltys Kulczynski, 1911 was originally described based on a single female specimen from western New Guinea. Three new species of the genus are reported here, M. baitetensis from eastern New Guinea, M. debakkeri from New Guinea and Cape York, and M. heatherae from north-eastern Australia and islands in the Torres Strait. No further specimens of Micropoltys placenta, the type species, have been discovered and this species is redescribed from the type female. Phylogenetic relationships of Micropoltys are briefl y discussed.

A new species of Argiope Audouin, 1826 is described. This is a large Argiope from South America and is found mainly in "cerrado" vegetation in central Brazil. Argiope legionis sp. nov. is most similar to A. ericae LEVI, 2004 but differs from this species by the coloration and epigynum in the female and the median apophysis and embolus of the palpus in the male palp.

This paper deals with two monotypic South-East Asian araneid genera: Deione Thorell, 1898 and Talthybia Thorell, 1898. Both sexes of a new species, Deione lingulata n. sp. are described. We provide morphological data on the male and illustrations of the genitalia of both sexes of Deione thoracica Thorell, 1898. The female of Talthybia depressa Thorell, 1898 is redescribed on the basis of the first adult female known specimen of the genus. Both genera are newly reported from China.

The examination of type material of presumed Australian orb-weaving spiders as part of a revision of the Araneidae of this country revealed that a number of species are not from Australia. The Natural History Museum, Vienna (Austria) holds the type material of three species of orb-weaving spiders that were originally described from Australia, however all of the species are undoubtedly of American, most likely southern Brazilian, origin and it is unlikely that they were collected in Australia. We propose the following synonymies and generic transfers: Acacesia tenella ( L. Koch, 1871) comb. nov. (= Acacesia cornigera Petrunkevitch, 1925 new synonymy); Alpaida navicula (L. Koch, 1871) comb. nov. (= Alpaida roemeri (Strand, 1908) new synonymy); and Eustala mucronatella (Roewer, 1942) comb. nov. In addition, Novearanea queribunda (Keyserling, 1887) comb. nov. (= Araneus quaesitus (Keyserling, 1887) new synonymy; = Novaranea laevigata (Urquhart, 1891) new synonymy) is a New Zealand orb-weaving spider based on the labels that were found with the type specimens housed at the Natural History Museum, London (England). In the original description no locality data was given for N. queribunda and "Australien" was erroneously listed for A. quaesitus.

The genus Mecynometa contains one species, M. glohosa O. Pickard-Cambridge 1889 that has three new synonyms. However, species belonging to two distinct genera, Alcimosphenus and Opas, had been included. Opas includes six known species. Two other Mecynometa species based on males, are synonyms of each other and appear to be the otherwise missing male of the common West Indian Alcimosphenus licinus Simon 1895. Male palpi of species of the three genera are illustrated for the first time. Three species of Leucauge are synonymized.

The name Madrepeira amazonica Levi 1995 is a synonym of Spintharidius rhomboidalis Simon 1893. Spintharidius is currently monospecific.

We trace the evolution of the web designs of spiders in the large family Theridiidae using two recent, largely concordant phylogenies that are based on morphology and molecules. We use previous information on the webs of 88 species and new data on the web designs of 78 additional theridiid species (representing nearly half of the theridiid genera), and 12 other species in related families. Two strong, surprising patterns emerged: substantial within‐taxon diversity; and frequent convergence in different taxa. These patterns are unusual: these web traits converged more frequently than the morphological traits of this same family, than the web traits in the related orb‐weaving families Araneidae and Nephilidae, and than behavioural traits in general. The effects of intraspecific behavioural 'imprecision' on the appearance of new traits offer a possible explanation for this unusual evolutionary plasticity of theridiid web designs. Key words: behavioural evolutioncobwebsbehavioural imprecision hypothesis Notes Corresponding author. Email: william.eberhard@gmail.com

The name Araneus beebei Levi 1941 is replaced by Araneus aragua. Araneus raui Levi 1973 is replaced by Araneus missouri. The species Araneus phrygiatus (Walckenaer 1842) is not recognizable based on the original description and considered a nomen dubium.

Of the 18 previously known Mangora species from South America, three names are synonyms and 12 species have their genitalia illustrated here for the first time. All of the 127 new species found are described, illustrated, and named. Most of these many species are found in the Amazon drainage. All the species outside the Amazon have only limited distributions except M. melanocephala, the most common Mangora, found between the Isthmus of Tehuantepec, Mexico, and northern Argentina. Only four species found in Central America extend their ranges to South America. A new method of immobilizing and examining palpi is described.

A new species of the genus Mastophora is described from Argentina. The male of M. vaquera is described from Cuba.

Nephila ?hil-to Taczanowski 1873 was described from French Guiana, but is currently listed under Nephilengys L. Koch. It is here redescribed and transferred from Nephilinae (Tetragnathidae)* to the araneid,enus Eusiala Simon, and proposed as a junior synonym of E. fuscovittota (Keyserling 1864). Eustala appears to be the most speciose American araneid genus and is in need of revision.

Thirty-two species of Mangora are found in the region under consideration. Three temperate species extend their ranges into northern Mexico, three Mexican species extend into the Southwest, and four species extend into South America. Only one species, M. melanocephala from Central America and South America, is both widespread and common. One species is found in the West Indies, including Trinidad. Of the 32 species, 15 are new. Six new synonyms are found. A few synapomorphies place Mangora close to Araneus.

Species placed in the genus Alcimosphenus are examined. Alcimosphenus licinus Simon 1895 is redescribed and validated. Alcimosphenus bifurcatus, A. rufoniger, A. boringuenae, Acusilas rufonigra and A. r. maculata are placed in synonymy. Alcimosphenus rubripleuris Mello-Leitao is transferred to Leucauge and redescribed.

The monotypic genus Melychiopharis Simon is transferred from Theridiidae to Araneidae, based mainly on characteristics of the male palp. Melychiopharis cynips Simon 1895 is redescribed and illustrated, including the first illustrations of a male specimen.

ABSTRACT There are one species of Gea and seven species of Argiope in the Americas. Distributions of Gea and Argiope species are recorded with new records from South America. Only one new species, A. ericae, from southern Brazil to northern Argentina, was found and is here described. The coloration of the female abdomen of Argiope species differs more than the visible differences of the genitalia. Males are separated by differences in palpi, the attachment of the embolus to stipes, and the shape of the coiled embolus.