Lower Jurassic foraminifera and calcified microflora from Gibraltar, Western Mediterranean

Benthic foraminifera are described for the first time from the Gibraltar Li mestone Formation of the Rock of Gibraltar. The new species Siphovalvulina colomi, S. gibraltarensis and Riyadhella praeregularis occur with Duotaxis metula Kristan, Everticyclammina praevirguliana Fugagnoli, Siphovalmlina sp ., an atypically early example of Textulariopsis sp., and Nodosaria sp. Mic roflora are present as the probable cyanobacterium Cayeuxia ?piae Frollo, t he alga Palaeodasycladus ?mediterraneus (Pia), and the disputed alga Thauma toporella ?parvovesiculifera (Raineri). The foraminifera compare most close ly with poorly-known taxa from Italy, Spain and Morocco, and are consistent with an Early Jurassic (Sinemurian) age for the upper part of the > 460-m- thick Gibraltar Limestone. Most are textulariids and more primitive than sp ecies well known from the later Early Jurassic (Pliensbachian) of the Medit erranean region, especially Morocco and Italy. The biota as a whole is char acteristic of inner carbonate platform environments widespread along the ri fted western margins of the Early Jurassic Tethys, notably those recorded f rom Morocco, Italy and Greece as well as southern Spain.