In this paper, we investigate the reproductive behavior of the gonyleptid Chavesincola inexpectabilis Soares & Soares 1946 (Heteropachylinae) and provide basic descriptive information about courtship, copulation, oviposition, and paternal care. Like most gonyleptids, males of C. inexpectabilis have a strong armature on the fourth pair of legs and use their spines and apophyses to fight other males and to repel them from their nesting sites. The mating pair interacts briefly before copulation, but the male touches the female both during and after penetration while she oviposits. The oviposition behavior differs markedly from that of other Laniatores: females hold the eggs on the chelicerae before depositing them on the substrate. After oviposition, the eggs are left under the guard of the male to defend against attack from cannibalistic conspecifics. Mapping the available data on reproductive biology of the Gonyleptidae on the phylogeny of the family, it is possible to infer that paternal care has evolved at least three times independently: once in the clade Progonyleptoidellinae Caelopyginae, once in the Gonyleptinae, and once in the Heteropachylinae, which occupies a basal position within the group.

Environments where prey availability is scarce or highly variable have been reported as potential settings for the occurrence of paternal investment and sex-role reversal (choosy males and competitive, courting females). Allocosa brasiliensis (Petrunkevitch 1910) and Allocosa alticeps (Mello-Leitão 1944) are two sand-dwelling wolf spiders that construct burrows along the Uruguayan coastline. Both species present a reversal in typical sex roles and size dimorphism. In the present study, we investigated foraging behavior and population density of both species by performing monthly samplings at the field during one year. Both Allocosa are general and highly opportunistic predators, varying their diet according to prey availability. The three most represented common prey belonged to Araneae, Diptera, and Hymenoptera (Formicidae). There were high levels of cannibalism in A. brasiliensis and, furthermore, males were observed frequently preying on conspecific adult females. Our discussion of the results based on hypotheses about food limitation and sex-role reversal contributes to our understanding of Allocosa species and establishes them as models for future evolutionary, behavioral, and ecological studies.

The harvestman fauna was studied along an altitudinal gradient on the southern slope of Lefka Ori Mountains, Crete, Greece for one year. Four sampling areas were defined at 800, 1200, 1600, and 2000 m elevation and they were sampled with pitfall traps that were emptied at monthly intervals. In total, six species were collected: Histricostoma creticum (Roewer 1927), Lacinius insularis Roewer 1923, Graecophalangium cretaeum Martens 1966, Opilio insulae Roewer 1956, Rafalskia cretica (Roewer 1923) and Leiobunum ghigii Di Caporiacco 1929. Species richness was the same (5 spp.) at the three lower zones and then declined to three species at 2000 m. Catches were more than double at this elevation. Differences of phenological patterns were observed among species and among altitudinal zones within the same species. High activity during spring and autumn and a summer recession were characteristic of most taxa. Opiliones did not seem strongly affected by the severe harshness of climatic conditions at higher elevations, as observed in other taxa, indicating a strong physiological tolerance and/or behavioral adaptation in order to withstand environmental stress.

Two female specimens of an undescribed species of stylocellid harvestman (Opiliones, Stylocellidae) from Sulawesi were extracted in methanol, and compounds in the product were identified by means of gas chromatography-mass spectrometry. Nineteen significant peaks were found, 12 of which were identified, indicating the presence of naphthoquinone, 2-tridecanone, 2-tetradecanone, 2-pentadecanone, 6-methyl-1,4-naphthoquinone, 6-methyl-1,4-naphthalenediol, and at least four unsaturated ketones. The spectrum differed both qualitatively and quantitatively from previously published data on Siro exilis Hoffman 1963 and Cyphophthalmus duricorius Joseph 1868 (Sironidae).

Two species of Chinchippus (Ammotrechidae) were studied in central Peru. Both species are endemic to the hyper-arid coastal desert and appear to derive most of their energy and nutrients from maritime prey, such as intertidal amphipods feeding on beach-cast algae or as arthropod scavengers feeding upon seabird and pinniped carcasses. Data on the spatial distribution of the two species were obtained from analyzing stomach contents of one common predator, the gecko Phyllodactylus angustidigitus, and suggest that both species are more abundant in insular than in mainland habitats. We redescribe Chinchippus peruvianus Chamberlin 1920, known only from a female specimen and describe the male for the first time while C. viejaensis is recognized as new. The new species is distinguished from C. peruvianus by its darker coloration, smaller size, and differences in cheliceral dentition.

We sampled 505 specimens of 7 arachnid orders (313 Araneae, 65 Opiliones, 111 Pseudoscorpiones, 10 Ricinulei, 3 Schizomida, 1 Thelyphonida, 2 Scorpiones) in natural forest and agroforestry sites in central Amazonia to analyze fresh and dry mass to body length relations. The low number of schizomids, scorpions, and thelyphonids did not allow statistical analyses, but the raw data are given, because these represent the first data published for these groups from Amazonia. For all other orders general mass-length relationships for ecological studies were determined. Non-linear regressions with a power model proved to describe the relations very well and are highly significant for all taxa and groups analyzed. The resulting equations can thus be used to estimate biomass of large samples of arachnids from Amazonia based on individual body length measurements. Linear regressions of mass to length with log-transformed data also described the relation adequately, but using the resulting equations to estimate biomass of the whole spider sample caused a higher bias. This is because small biases of mass-length relation of the largest spider individuals are exponentiated. However, linear regressions behaved better for spiders smaller than 8 mm. The ratio of dry to fresh mass was around 0.3 for spiders; 0.4 for pseudoscorpions, schizomids, and thelyphonids; 0.44 for opilionids; and 0.53 for Ricinulei. A second sample of 99 spiders from a South Brazilian Atlantic Forest revealed similar mass-length relations, but a different dry to fresh mass ratio. For spiders, the usefulness of general equations to determine the biomass of bulk samples from ecological studies with certain precision requirements was further explored by using the equations from the two datasets crosswise, regarding the resulting bias and by applying equations to a further dataset from an ecological investigation. In conclusion and accordance to former studies, general equations derived from mass-length regressions of bulk samples including many specimens of different families and guilds are appropriate for an estimation of the biomass of bulk samples from ecological studies. Equations from mass-length regressions from the literature, resulting from spider samples in temperate regions, should not be used to estimate biomass of samples from neotropical spider assemblages, especially when absolute biomass is of interest and when precision is required. They underestimate biomass of tropical assemblages due to a strong bias in mass-length relation of tropical spiders larger than 10 mm. Depending on the distribution of large spiders in samples, considerable biases in single samples could affect ecological analyses.

Two new species of the spider genus Ochyrocera Simon 1891 are described from Mexico. Ochyrocera juquila new species was collected under moist rotten logs and hollow trunks on a thick bed of pine needles in oak-pine forests located in a mountain range south of the city of Oaxaca at 1400–2700 m elev. Ochyrocera juquila resembles O. quinquevittata Simon 1891 from the Island of St. Vincent, in the angular shape of the embolus, which in the new species is V-shaped and in O. quinquevittata is L-shaped. Ochyrocera chiapas new species, was collected under rotten trunks and hollow trunks in abundant leaf litter in the tropical, humid Lacandona rainforest region located in eastern Chiapas, near the border with Guatemala. The species occurs at 160–260 m elev. Ochyrocera chiapas resembles O. arietina Simon, 1891 from the island of St. Vincent, in the similar shape of the embolus and distal apophysis of the cymbium, but in O. chiapas the embolus is more strongly curved and directed toward the distal part of the tibiae forming a “D”; in O. arietina the embolus is not as strongly curved as in O. chiapas. In both species, males and females were collected near each other; the females carried their egg sacs with their chelicerae. A key to the four known Mexican species is provided.

The genus Diplothele O. Pickard-Cambridge 1890 of the brush-footed spider family Barychelidae is represented in India by a single species, D. walshi O. Pickard-Cambridge 1890. In this paper, we describe two new species: Diplothele gravelyi from Angul and Diplothele tenebrosus from Ganjam, Orissa. We establish a neotype and provide additional characters for D. walshi, the types of which are lost. The neotype was collected from one of the previously described localities, Barkuda Island, Orissa. Spiders of this genus are known to build double-door trapdoor burrows, but the new species, D. tenebrosus, constructs a single entrance burrow with a trapdoor. Notes on natural history are provided for all species.

A new pirate spider (family Mimetidae) is described as Australomimetus mendax new species from Tasmania, Australia. In this context, all mimetid species currently known from the island have been reviewed and re-illustrated. Five species are recorded and they all belong to the genus Australomimetus Heimer 1986. Re-illustrated here are Australomimetus maculosus (Rainbow 1904), A. tasmaniensis (Hickman 1929) new combination, A. aurioculatus (Hickman 1929) new combination and A. audax (Hickman 1929) new combination. We briefly discuss the phylogenetic relationships of these species and provide distribution maps of their Tasmanian records. Australomimetus mendax is the only species currently endemic to Tasmania. All other species exhibit wide distribution patterns from tropical Queensland to Western Australia. The ranges of A. aurioculatus and A. audax – species originally thought to be Tasmanian endemics – are now extended to include the Australian mainland as well. The cosmopolitan genus Mimetus Hentz 1832 is restricted and excludes all pirate spiders with a Tasmanian distribution.

Rhopalurus abudi Armas & Marcano Fondeur 1987 was originally described on the basis of a single female specimen from Isla Saona, La Romana Province, off the southeast coast of the Dominican Republic. The species is redescribed here based on a series of new specimens including 19 adult males and 14 adult females collected at two nearby localities on the eastern side of Parque Nacional del Este, La Altagracia Province, southeastern Dominican Republic. These specimens represent the first records of R. abudi on mainland Hispaniola and the first male specimens of the species to be collected.

The wolf spider genus Zoica Simon 1898 is currently known only from the Indo-Australasian region, including India in the west to northern Western Australia and Papua New Guinea in the east. Here we extend the known distribution of the genus into the Pacific region by describing two new species, Z. carolinensis new species from the Caroline Islands, Federated States of Micronesia, and Z. pacifica new species from the Republic of the Marshall Islands.

We predicted that because plant nectar is high in energy, it is likely to provide multiple benefits to spiders that spend a substantial amount of energy foraging. In three laboratory experiments, we tested the effects of dietary extrafloral nectar on the survival, molting, and activity of two foliage wanderers, Cheiracanthium mildei L. Koch 1864 (Miturgidae) and Hibana velox (Becker 1879) (Anyphaenidae), both highly active, quick-moving nocturnal foragers. Extrafloral nectar contributed significantly to survival and molting in prey-deprived H. velox. On a marginal diet of prey (one Drosophila adult on alternate days) offered to spiders as soon as they emerged, 97% of C. mildei underwent their first molt if they also received nectar, compared to 7% of controls without nectar. On a marginal diet of prey (one Drosophila adult on alternate days) offered to spiders starting two days after their emergence, 78% of the spiders also receiving nectar molted, compared to 0% of controls without nectar. Video recordings of activity showed that prey-deprived groups of C. mildei maintained their active nocturnal foraging for many days on nectar, whereas controls became increasingly quiescent until they died. Non-web-building spiders that feed on nectar may utilize its energy for foraging and thereby allocate the nutrients of prey to maintenance and growth.

The harvestmen Caddo agilis Banks 1892 and C. pepperella Shear 1975 (Caddidae, Caddinae) share a disjunct distribution in eastern Asia and eastern North America that has been attributed to either recent (Pleistocene) evolution of a C. pepperella morph from C. agilis in each region or to a pre-glacial separation within each of two established species. The present study used 2,130-base sequences from two nuclear protein-coding genes (EF1α, Pol II) to test the phylogenetic predictions of both hypotheses using representatives from the two Caddo species from both regions and two acropsopilionine outgroup species. The results supported the hypothesis that the two Caddo species were distinct prior to their respective biogeographic disjunctions; C. agilis and C. pepperella were each recovered as monophyletic and each appears to have undergone separation into Asian and North American groups.

Acrocerid flies are endoparasitoids of spiders. New host associations are reported for Ogcodes melampus Loew 1872, O. eugonatus Loew 1872, and Acrocera sp. (Group IV; sensu Sabrosky 1944) from reared individuals of two Salticidae species, Pelegrina proterva (Walckenaer 1837) (both Ogcodes species), and Eris militaris (Hentz 1845) (the Acrocera sp.) (Group IV; sensu Sabrosky 1944). The spiders were sampled in the canopy and understorey of a mature north-temperate hardwood forest at the Morgan Arboretum, Québec, Canada.

Toca new genus is proposed to include two new species: the type species T. bossanova new species from Rio de Janeiro, Brazil, and T. samba new species from Paraná and Minas Gerais, Brazil. Toca may be related to Caloctenus Keyserling and Gephyroctenus Mello-Leitão, with which it shares the scales on the abdominal dorsum and the epigynum as a single, slightly sclerotized, fold. The genus can be distinguished among the Calocteninae genera by its unique genital structures.