Preserved skeletal remains of the holotype of D. modularis gen. et sp. nov. (ZMNH M8782).

Holotype ZMNH M8782 (a,b,e) and referred specimen YH-2000 (f) of D. modularis gen. et sp. nov.: (a) cranium and mandibles in the right lateral view, cervicals 1–4 in the dorsal view, scale bar 5 cm; (b) details of the dentition in the anterior tip of the rostrum, scale bar 2 cm; (c) restoration of the skull, scale bar 5 cm; (d) restoration of the right pes in the anterior view, scale bar 2 cm; (e) details of the seventh to ninth caudal vertebrae and bony rods that enclose them, scale bar 0.5 cm; (f) complete skeleton seen in the ventral aspect, except for skull which is in the right lateral view, scale bar 5 cm. Abbreviations: a, articular; cr, cranial crest; d, dentary; f, frontal; j, jugal; l, lacrimal; ldt, lateral distal tarsal; m, maxilla; mdt, medial distal tarsal; met, metatarsal; n, nasal; naof, nasoantorbital fenestra; p, parietal; pd, pedal digit; pf, prefrontal; pm, premaxilla; po, postorbital; q, quadrate; qj, quadratojugal; sq, squamosal; ti, tibia.

Comparison of D. modularis gen. et. sp. nov. to other pterosaurs: (a) skull as a proportion of body length (DSV) plotted against a proxy for size (length of the humerus in mm); (b) relative length of the neck; (c) relative length of metacarpus. Filled circles, basal forms; crosses, pterodactyloids; stars, Darwinopterus.

Phylogenetic relationships and evolutionary context of Darwinopterus. (a) Phylogenetic analysis of Pterosauria (see the electronic supplementary material for details), possible alternative locations for Darwinopterus indicated by D1 and D2. (b) Schematic restorations of a basal pterosaur (above), Darwinopterus (middle) and a pterodactyloid (below) standardized to the length of the DSV, the arrow indicates direction of evolutionary transformations; modules: skull (red), neck (yellow), body and limbs (monochrome), tail (blue); I, transition phase one; II, transition phase two. (c) Time-calibrated phylogeny showing the temporal range of the main pterosaur clades; basal clades in red, pterodactyloids in blue; known ranges of clades indicated by solid bar, inferred ‘ghost’ range by coloured line; footprint symbols indicate approximate age of principal pterosaur track sites based on Lockley et al. (2008); stratigraphic units and age in millions of years based on Gradstein et al. (2005). 1, Preondactylus; 2, Dimorphodontidae; 3, Anurognathidae; 4, Campylognathoididae; 5, Scaphognathinae; 6, Rhamphorhynchinae; 7, Darwinopterus; 8, Boreopterus; 9, Istiodactylidae; 10, Ornithocheiridae; 11, Pteranodon; 12, Nyctosauridae; 13, Pterodactylus; 14, Cycnorhamphus; 15, Ctenochasmatinae; 16, Gnathosaurinae; 17, Germanodactylus; 18, Dsungaripteridae; 19, Lonchodectes; 20, Tapejaridae; 21, Chaoyangopteridae; 22, Thalassodromidae; 23, Azhdarchidae. Abbreviations: M, Monofenestrata; P, Pterodactyloidea; T, Pterosauria; ca, caudal vertebral series; cv, cervical vertebral series; mc, metacarpus; na, nasoantorbital fenestra; r, rib; sk, skull; v, fifth pedal digit.