Molecular identification of spiders preying on Empoasca vitis in a tea plantation.

Biological control using predators of key pest species is an attractive option in integrated pest management (IPM). Molecular gut analysis can provide an estimation of predator efficiency on a given prey. Here we use a combination of various experimental approaches, both in field and lab, to identify a potential biological control species of the common pest of commercially grown tea, Empoasca vitis (Göthe) (Hemiptera), in a Chinese plantation. We collected 2655 spiders from plantations and established relative abundances of spider species and their temporal overlap with the pest species in tea canopy. We analyzed DNA from 1363 individuals of the most common spider species using targeted RQ-PCR to quantify the potential efficiency of spiders as a predator on E. vitis. The results showed that, in the field, the jumping spider Evarcha albaria was the most abundant, had the closest temporal overlap with the pest, and frequently fed on it. Therefore, this spider may play a key role in pest suppression. The present study demonstrates the potential of our experimental approach to study predator-prey relationships in taxa that do not lend themselves to morphological identification of gut contents, such as spiders.

The first fossil spider (Araneae: Palpimanoidea) from the Lower Jurassic (Grimmen, Germany).

The first Lower Jurassic (Lias) spider is described as Seppo koponeni n. gen. & n. sp. from a single female specimen from Grimmen, Germany. It most likely belongs to the Palpimanoidea, on account of the presence of cheliceral peg teeth and other features consistent with palpimanoid families, though its familial placement is uncertain. Its presence in the region at that time concurs with ideas about the more widespread presence of palpimanoids across the world in the early Mesozoic, before the break-up of Pangaea.

The oldest haplogyne spider (Araneae: Plectreuridae), from the Middle Jurassic of China.

New fossil spiders (Arachnida: Araneae) from Middle Jurassic (ca. 165 Ma) strata of Daohugou, Inner Mongolia, China are described as Eoplectreurys gertschi gen. et sp. nov. and referred to the modern haplogyne family Plectreuridae. This small family is restricted to southwestern USA, Mexico, and the adjacent Caribbean area today and hitherto has only a sparse Cenozoic fossil record. The morphology of Eoplectreurys is remarkably similar to modern forms and thus demonstrates great evolutionary conservatism. This new discovery not only extends the fossil record of the family by at least 120 Ma to the Middle Jurassic but also supports the hypothesis of a different distribution of the family in the past than today and subsequent extinction over much of its former range.

The first cytogenetic characterization of the poisonous black widow spider Latrodectus gr. curacaviensis from Brazil, with chromosomal review of the family Theridiidae (Arachnida, Araneae)

In this paper we present, for the first time, cytogenetical data on Latrodectus gr. curacaviensis (Theridiidae) from Brazil, as well as the first data on meiosis and sex chromosome system of this genus. Testes were submitted to colchicine, hypotonic, and fixation treatment, and chromosomal preparations were stained with Giemsa solution. The analysis showed 2n=26 telo/acrocentric chromosomes in spermatogonial metaphases. Metaphase I exhibited 12 autosomal bivalents and two sex chromosome univalents (12II+X1X2). All bivalents revealed one terminal chiasma. Metaphases II confirmed the sex chromosome system, showing 12 autosomes or 12 autosomes plus two X chromosomes, respectively. Male karyotype prevailing in theridiids is formed by 2n=22 chromosomes, including sex chromosome system X1X2 in all species. The Latrodectus species of the geometricus clade analyzed until now showed smaller diploid number (2nŠ=16 and 2nŠ=18) than the species of the mactans clade (2nŠ=24 and 2nŠ=26). Thus, according to the chromosome number, the examined Latrodectus species seems to be related to the mactans clade.

Medical aspects of spider bites.

Spiders have been incriminated as causes of human suffering for centuries, but few species worldwide cause medically significant envenomation. Widow spiders (Latrodectus spp.) occur worldwide and cause latrodectism, which is characterized by pain (local and generalized) associated with nonspecific systemic effects, diaphoresis, and less commonly other autonomic and neurological effects. Recluse spiders (Loxosceles spp.) are distributed mostly through the tropical and subtropical Western Hemisphere and can cause severe skin lesions and rarely systemic effects; most bites are unremarkable. Highly dangerous spiders in South America (armed spiders) and Australia (funnel-web spiders) cause rare but severe envenomation requiring medical intervention and sometimes antivenom. Most other spiders involved in verified bites cause minor, transient effects. Many spiders blamed for causing medical mischief have been elevated to medical significance via circumstantial evidence, poor reporting, and repetitive citation in the literature; several species have been shown to be harmless with more stringent scientific evidence involving verified bites in humans.

[Steatoda spider envenomation in southern France]. / Un cas de stéatodisme observé en Languedoc après morsure d'araignée du genre Steatoda.

INTRODUCTION: Cobweb spiders (genus Steatoda) are small species closely related to black widow spiders and their bites can induce envenomation known as steatodism. CASE: A 46-year-old man in the Gard district in southern France was sleeping in his bed when a spider (identification Steatoda triangulosa) bit him. Clinical manifestations included local signs together with systemic neurological symptoms resembling low-grade latrodectism (black widow envenomation). DISCUSSION: This first-recorded case of steatodism in southern France differs in several ways from the classic pattern of latrodectism in Europe: the bite occurred in home during winter and mild symptoms resolved quickly without hospital care. CONCLUSION: In endemic areas (in France the Mediterranean climate zone: Provence, Languedoc and Corsica), steatodism should be considered when low-grade latrodectism is observed.

Bird-spiders (Arachnida, Mygalomorphae) as perceived by the inhabitants of the village of Pedra Branca, Bahia State, Brazil.

This paper deals with the conceptions, knowledge and attitudes of the inhabitants of the county of Pedra Branca, Bahia State, on mygalomorph spiders locally known as 'caranguejeiras' (bird-spiders). It is launched here a new filed within ethnozoology: ethnoarachnology, which is defined as the transdisciplinary study of the relationships between human beings and bird-spiders. Data were collected from February to June 2005 by means of open-ended interviews carried out with 30 individuals, which ages ranged from 13 to 86 years old. It was recorded some traditional knowledge regarding the following items: taxonomy, biology, habitat, ecology, seasonality, and behavior. Results show that bird-spiders are classified as "insects". The most commented aspect of the interaction between bird-spiders and inhabitants of Pedra Branca is related to their dangerousness, since they said these spiders are very venomous and can cause health problems. In general, the traditional zoological knowledge of Pedra Branca's inhabitants concerning these spiders is coherent with the academic knowledge.

Management of brown recluse spider bites in primary care.

BACKGROUND: Treatment of brown recluse spider bites remains controversial; there are multiple options but little evidence of their effectiveness. METHODS: Over a 5-year period, family physicians enrolled consecutive patients with suspected brown recluse spider bites. Usual care was provided based on physician preferences. Topical nitroglycerine patches and vitamin C tablets were provided at no cost for those who wished to use them. Baseline data were collected, and patients were followed-up weekly until healing occurred. Outcome measures included time to healing and occurrence of scarring. Regression methods were used to evaluate the impact of the 4 main treatment approaches (corticosteroids, dapsone, topical nitroglycerine, and high-dose vitamin C) after controlling for bite severity and other predictors. RESULTS: Two hundred and sixty-two patients were enrolled; outcomes were available for 189. The median healing time was 17 days. Only 21% had permanent scarring. One hundred seventy-four received a single treatment modality. Among this group, 12 different modalities were used. After controlling for other variables, predictors of more rapid healing included lower severity level, less erythema, and less necrosis at time of presentation, younger age, no diabetes, and earlier medical attention. Systemic corticosteroids and dapsone were associated with slower healing. Predictors of scarring were higher severity, presence of necrosis, and diabetes. Dapsone was associated with an increased probability of scarring. CONCLUSIONS: We found no evidence that commonly used treatment approaches reduced healing time or the likelihood of scarring in suspected brown recluse spider bites.

Black widow spider and brown recluse spider bites in Texas from 1998 through 2002.

Black widow spiders and brown recluse spiders are of medical importance to humans in the US. However, these spiders differ in their habits, habitat, and the clinical effects and treatment of their bite. This study used data from human exposure calls to poison centers in Texas to compare the epidemioloy of bites from these 2 spiders. During 1998-2002, 760 black widow spider bites and 1,369 brown recluse spider bites were reported. Black widow spider bite penetrance demonstrated no secular trend during this time period while the penetrance of brown recluse spider bites increased. A higher percentage of black widow spider bites occurred among males, while a higher proportion of brown recluse spider bites were reported for females. Black widow spider bites most frequently had mild outcomes while brown recluse spider bites most often had moderate outcomes. The majority of reported bites for both types of spider occurred at the patient's own residence, although the percentage was lower for black widow spiders. Seasonal trends were noted for both black widow and brown recluse spiders. The highest penetrance of black widow spider bites was observed in western Texas while the highest penetrance of brown recluse spider bites was observed in central Texas. This information is useful for identifying those populations at greatest risk for the respective spider bites.

[The "hornet spider" of Plinius]. / Zur "Hornissen-Spinne" des Plinius.

Pliny the Elder describes in his 'Natural History' XXIX 86 a species of spider dangerous for human beings and looking like a hornet without wings. This description corresponds to Solipugae of the genus Karschia, living in arid areas of Central Asia. These animals are not venomous but can cause harm by their powerful bite and in some cases by a following inflammation of the wound. On the contrary, an animal called "wasp-like", mentioned by Nikander of Kolophon ('Theriaca', v. 738-746) and often regarded to be the same creature, seems to be a typical venomous spider which causes an acute intoxication by its bite.

Acute and recurrent skin ulceration after spider bite.

We reviewed the records of the Australian Venom Research Unit and The Alfred Hospital Department of Hyperbaric Medicine from January 1992 to July 1998 and found 15 cases of skin ulceration after spider bite that could be followed up with the patient and the treating physician. Fourteen patients had skin ulceration attributed to white-tailed spider bites but in only three was this confirmed. One patient had skin necrosis after a confirmed black house spider bite. Recurrent skin ulceration occurred in nine of the 15 patients.

The toxicology of the Latrodectus hasselti spider--the Australian red back spider.

The zoology and behaviour of Latrodectus hasselti, the Australian red back spider is described. The symptoms of envenomation are discussed; the most prominent symptom is pain of various types in the head, abdomen and limbs.