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The aim of this work is to show late Tithonian palaeogeography and palaeoenvironments of the Tethys on a map on the scale of 1/20,000,000. The plate setting is based on geodynamic maps of the Alpine-Himalayan [Ricou et al., 1989], Caribbean [Stephan et al., 1990] and Atlantic [Klitgord and Schouten, 1986] domains. The maps of the northern margin of the Tethys in the Alpine domain have also been used [Dercourt et al., 1990]. The data on the facies identified in this domain, which ranges from western Americas up to Himalaya, have been taken from: (1) personal work of the authors; (2) the review of a huge bibliography. The whole has been interpreted in terms of palaeoenvironment.

The areal distribution of the different facies allows us to map 12 major palaeoenvironments. All the emerged lands which frame the Tethys, often bear evaporites thus indicating warm and arid climates.

The margins of Africa, Iberia and Apulia are characterized by shallow-water carbonate platforms, sometimes isolated. They also develop on the Florida-Bahamas platform and on Maya block.

The pelagic, often chert-bearing, Calpionella, limestones, usually known with the name Maiolica, were world-widely distributed. The red nodular Ammonitico Rosso limestones were very scarce and scattered in a few outcrops of the Mediterranean branch of the Tethys. Radiolarities also had a very restricted geographical distribution; they especially occurred on the largely opened eastern branch (<>). Flysch only occurs in small areas at late Tithonian time. Subduction-related volcano-clastic sequences are very scarce; they have been reported from the eastern part of the northern margin of the Tethys and around the Chortis (Honduras) block. Organic matter was very scarce.