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protoliths of the metasedimentary rocks of the Serie Negra Group are Ediacaran (~590-541 Ma) in age (Schäfer et al . 1993; Ordóñez Casado 1998; Linnemann et al . 2008; Ordoñez Casado et al . 2009; Pereira 2015). This group is exposed in SW Iberian Massif (Carvalhosa 1965; Eguiluz and Quesada 1980; Abalos 1987), but it also has correlatives in the Bohemian Massif (Linnemann and Romer 2002; Linnemann et al . 2008). The sedimentary series was the host to a compositionally complex variety of intrusive igneous rocks. The (finer-grained) metabasites cited above can be distinguished from metagrabbros that occur as coar- ser-grained rocks in larger patches and which are spa- tially associated with metatonalites. Some metagabbros preserve a primary (equigranular) igneous texture. Differences in grain size between the latter and fine- grained metabasites are not observed in high strain zones. Therefore, current differences in grain size may be related to its primary texture (basalts/microgabbros vs. gabbros). Metatonalites, metagranodiorites (Figure 6 (e)), and metagranites (Figure 6(f)) occur as variably strained, kilometre-scale bodies within the metasedi- mentary rock series (Figures 3 and 4). Sections of these bodies accumulating more strain can be observed as mafic, intermediate, or felsic orthogneisses (Figure 7 (a)), respectively, whereas poorly strained sections show the primary texture of their protoliths. Introducing details on the range of primary textures exceeds the purpose of this contribution, but as a preliminary approach, all metagranitoids presented Figure 6. (a) Metaperidotite (metaharzburgite) from the Mérida Ophiolite consisting of serpentine pseudomorphs after olivine (>60%) and lesser amounts of strongly serpentinized orthopyroxene (cross polarizers to the right; Ol: serpentinized olivine; OPx: serpentinized orthopyroxene). (b) Folded main foliation in schists from the Upper Schist-Metagranitoid Unit (blue lines). Axial planes (red lines) are parallel to Variscan foliation (S V ) and show similar strike to left-lateral faults (white lines). (c) Variscan antiform (hinge line in red) affecting bedding, main foliation and lineation (blue line) of black quartzites from the Upper Schist-Metagranitoid Unit. (d) Fine- grained metabasite from the Upper Schist-Metagranitoid Unit (main foliation in blue). (e) Poorly strained meta-granodiorite from the Upper Schist-Metagranitoid Unit. (f) Main foliation (blue line) in moderately strained felsic to intermediate metagranite from the Upper Schist-Metagranitoid Unit. Note penetrative fracture network (dark bands) affecting the protolith. INTERNATIONAL GEOLOGY REVIEW 7 Tectonostratigraphy of the Mérida Massif