David Ortiz-Villatoro

Acanthoscurria cordubensis (fig. 1A) and Eupalaestrus weijenberghi (fig. 1B) are two tarantulas which inhabit meadows in Uruguay. During the last decades, there has been intense modifications of natural grassland environments, mainly due to agriculture and forestation. We decided to compare the presence and distribution of both species from results...

Theraphosid tarantulas are large spiders that bear dense hairy adhesive pads on the distal parts of their legs: scopula and claw tufts. These structures allow them to climb on vertical smooth surfaces and contribute to prey capture. While adult females and juveniles remain most of the time in their burrows, adult males actively walk searching for f...

Most of the New World tarantulas feature specialized setae as a defense mechanism. Two mechanisms of defense have been proposed for the urticating setae (US): active defense against potential predators, and passive defense against other arthropods by incorporating the US to the molting mat and egg sacs. Uruguayan tarantulas present three different...

Tarantulas are large spiders with adhesive setae on their legs, which enable them to climb on smooth vertical surfaces. The mechanism proposed to explain adhesion in tarantulas is anisotropic friction, where friction is higher when the leg pushes compared to when it pulls. The static friction of live theraphosid spiders on different surfaces and at...

When two similar species co-occur in time and space, strong mechanisms isolating them from each other are expected. Acanthoscurria suina Pocock, 1903 and Eupalaestrus weijenberghi (Thorell, 1894) are two sympatric and synchronic tarantulas that inhabit burrows in Uruguay's meadows. Here we test how and when reproductive isolation operates between t...

Theraphosid tarantulas, like all other spiders, secrete silk from spigots on the abdominal spinnerets. A few years ago, it was proposed that the large tarantula Aphonopelma seemanni could extrude silk from specialized spigots on the tarsi to help adhesion to vertical surfaces. This suggestion was later questioned because silk was not observed after...

As with all spiders, tarantulas spin silk from specialized structures in the abdomen called spinnerets, which are key features unique to the group. Recently Gorb et al. reported that the zebra tarantula Aphonopelma seemanni also secretes silk from its feet, which might improve its ability to climb on vertical surfaces. Here we show that when the sp...