The ecribellate haplogyne spiders of the genus Loxosceles Heineken & Lowe, 1832, known as recluse or violin spiders, are well known because of their ability to occasionally cause significant skin necrosis also known as loxoscelism (Vetter, 2008; Saupe et al., 2011). The venom of these spiders contains an unusual enzyme, sphingomyelinase D, which, when incorporated into the skin and subcutaneous tissues, ultimately causes platelet aggregation, endothelial hyperpermeability, hemolysis, and neutrophil-dependent skin necrosis (Saupe et al., 2011). Based on the morphology of their spinnerets these spiders are now classified in the sub-family Loxoscelinae, in the Sicariidae (Gertsch 1949; Gertsch, 1967; Gertsch and Ennik 1983; Vetter, 2008). The family Sicariidae currently includes spiders of only two genera, Loxosceles with more than 100, and Sicarius Walckenaer, 1847 with more than 21 described species respectively (Platnick, 2013). The Mediterranean recluse, L. rufescens (Dufour 1820), is a widely distributed species, originating from somewhere in the circum-Mediterranean region but has been distributed to other regions by means of human activity (Harvey, 1996). This species is now reported from Mediterranean countries and other regions including Turkmenistan, East Asia, United States and Australia (Harvey, 1996; Yigit et al., 2008). There were unidentified records of the genus Loxosceles from Iran (Goodarzi, 1994; Moradmand and Jäger, 2011; Kashefi et al., 2013) but, the first record of the Mediterranean recluse spider, L. rufescens, was provided by Zamani and Rafinejad (in press) from Tehran Province. This species is distinguished from its closely related species by the following characteristics: the tibia of male’s palp is short, thick and not very prolonged. The embolus is about as long as the width of the globular bulb (Fig.1, 3); paired spermathecae, closed together at the midline, with single large and rounded lobe (Fig. 2, 4). In this paper we provided a new data on the geographic distribution of L. rufescens and its envenomation from northeast of Iran (Fig. 5). All specimens were collected in daytime from houses. The examined specimens are preserved in the Zoological Museum, Ferdowsi University of Mashhad, Mashhad, Iran (ZMFUM). Whole specimens, male palps and vulva were photographed using an Olympus DP-71 camera connected to an Olympus SZH-10 stereomicroscope. The vulvas were macerated either with KOH or lactic acid.

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