This reminded me that I had found the website of Paul Selden where he has kindly made available many of his publications on fossil spiders available: http://homepage.mac.com/paulselden/Home/index.html
MYGALOMORPH SPIDERS (ARANEAE: DIPLURIDAE) FROM THE LOWER CRETACEOUS CRATO LAGERSTÄTTE, ARARIPE BASIN, NORTH-EAST BRAZIL
by PAUL A. SELDEN, FABIO DA COSTA CASADO and MARISA VIANNA MESQUITA
Palaeontology Volume 49 Page 817 - July 2006
Abstract: The first mygalomorph spiders from the Lower Cretaceous Crato Lagerstätte of Cearà Province, north-east Brazil, are described, from adult males and females, in two new genera and species: Cretadiplura ceara Selden, gen. et sp. nov. and Dinodiplura ambulacra Selden, gen. et sp. nov. They belong to the extant family Dipluridae, hitherto known as fossils only from Tertiary strata; thus this occurrence extends the family record by some 90 myr.
See also: Santana Formation Fossils and my post: oldest orb weaving spider discovered