Alongside the well-known Upper Cretaceous (Maastrichtian) dinosaur-bearing continental deposits of the Haţeg Basin [18] , another set of important Maastrichtian vertebrate sites are located in the Sebeş-Alba region of Romania, about 50 km northeast of Haţeg ( Figure 1 ). Here, Upper Cretaceous sediments form a large-scale transgressive–regressive cycle involving deep-to-shallow marine deposits and continental red beds of Campanian-Maastrichtian age, related to the Laramidian tectonic event [19] , [20] . From a stratigraphic point-of-view, the Upper Cretaceous-Paleogene continental deposits in the Sebeş area are represented by several formations that belong to two main tectonostratigraphic megasequences, covering the Santonian–Rupelian interval [13] , [21] , [22] . The Maastrichtian vertebrate-bearing continental deposits here have been referred either to the recently re-dated Sebeş Formation (SBF) [13] , [14] , well exposed on the left flank of the Mureş passageway (Secaş Plateau and the Sebeş Valley), or to the Vurpăr (VPF) and Şard (SDF) formations that outcrop on the right flank of the Mureş Valley in the Munceii Vinţului (VPF) and Bilag (SDF) foothills ( Figure 2 ). The whole succession in this region is characterised by lacustrine muds, medium-to-coarse channel associations, and extensive floodplain and overbank facies [13] , [23] ( Figure 3 ). The SBF comprises a thick succession of alluvial deposits of dark bluish or gray mudstone, red, dark-brown or yellowish-brown claystone, red silty-clays, and medium-to-coarse poorly-sorted conglomerates with reddish or grayish mostly cross-laminated sandstone interbeds ( Figure 3 ). Deposition took place under various conditions, from proximal alluvial fans to the medium and distal facies of meandering, occasionally braided, fluvial systems that exhibit local evidence for well-developed lacustrine, forrested-swampy, short evaporitic stages and extensive pedogenized floodplain deposits. The thickness of the SBF is approximately 450 m between Sebeş and Râpa Roşie (Red Cliff) the historically designated type section [13] , [21] and is unconformably overlapped by transgrading middle Miocene (lower Badenian) marine deposits.

A relatively large number of vertebrate fossils are so far known from the SbG/B site and these originate mainly from the red overbank deposits. Most are fragmentary, isolated bones but more complete elements, closely associated and partially articulated skeletons have also been collected. Upstream from this site, in minor channel deposits associated to OF facies (SbG/C and D sites), mostly fragmentary bones of turtles, crocodylomorphs and sauropod dinosaurs, as well as numerous plant remains, are common. The fauna from here is so far known to comprise various ornithopod (Zalmoxes, Telmatosaurus), sauropod (Magyarosaurus; Titanosauria indet.) and theropod (Balaur) dinosaurs, abundant stem-turtles (Kallokibotion) and two crocodylomorphs alongside rarer remains of pleurodiran turtles (Dortokidae), birds and azhdarchid pterosaurs [17] . Of the latter, the new specimen presented here is the most complete European Maastrichtian azhdarchid found to date.

The SbG/B site (from were EME VP 312 was collected) is a small, waterlogged riverbank outcrop, slightly eastward dipping and 6.5 m thick in profile ( Figure 3 ). The basal channel association here is comprised of upward-fining, medium-to-coarse, occasionally pebbly, light pinkish-gray sandstones, grouped in several meters thick progressively thinner trough cross laminated sets that show internal truncation (St/Sp). These sediment associations characterise a lateral accretional facies (LA). Progressive abandonment and lateral migration of the channel is marked by fine, horizontally laminated sands-silts-clays with occasional scour-fill features and flute-marks. These indicate minor crevasses (Sh/Fl), grading into reddish sandy-silty claystone and a mudstone-dominated proximal floodplain association (OF). Fossiliferous layers are grouped into a 2.2 m thick dark-red calcareous silty-claystone sequence that has thinly-laminated and lenticular sandy interbeddings (crevasses), related to periodic flooding events, and several pedogenic calcitic horizons (Bk) that are marked by sparse and occasionally grouped calcareous nodules. Bone fragments and chips are widespread throughout the whole overbank sequence: however, more complete elements of closely associated and/or articulated skeletal parts are to be found immediately above the sandy crevasses, covered by fine sediments. The top of the overbank facies is represented by massive dark-red mudstone, showing abundant tubular burrowings and rhysolites, marking the incipient topsoil horizon. A several-metres-thick, poorly sorted, massive, plannar or concoid cross-laminated multistoried conglomerate channel-fill complex (Gmm, Gp/Gh) covers the whole sequence, bounded by a 4 th order flat lower surface. In the basal lag deposits, large cobble-size, reddish sub-angular claystone rip-up clasts are common. The multistory complex CH fills, dominated upward by truncated cross-bedded sets (Gh), may indicate mobile, broad and shallow channels. In such circumstances, a more unstable and dynamic environment, with frequent reactivations and flow direction changes can be reconstructed.

Sebeş-Glod (here coded SbG/A-D) is comprised by suite of restricted outcrops that are located from 1.5 to 3 km north of Sebeş City in Alba County, Romania ( Figure 2 ). All these sites are downstream, alongside, and often in, the Sebeş River and have been briefly discussed by Vremir [13] , Csiki et al. [16] , Codrea et al. [23] and Brusatte et al. [17] . Here, a roughly 50 m thick profile from the mid-lower section of the SBF, probably late Early Maastrichtian in age, outcrops about 300–350 metres below a major middle-Miocene (Badenian) unconformity that caps the SBF at the Râpa Roşie type section. This profile is also approximately 100 m above the top of the conformably underlying Bozeş Formation (upper Campanian– ?lowermost Maastrichtian) that is well-exposed in the Petreşti-Arini section [15] . The succession here is dominated by coarse, mainly cross-bedded channel associations (i.e., gravel, sandy gravel and cross-laminated sandstones) that are related to a high sinuosity fluvial system, with occasional interbeds of finer-grained red or brownish-red overbank and floodplain associations ( Figure 3 ).

EME VP 312 can be referred to the pterodactyloid clade Azhdarchidae due to the presence of the following characters in its cervical vertebrae: (1) extreme elongation of mid-cervicals; (2) reduced and/or vestigial neural spine; (3) tube-like cervical centra [26] – [29] . Similar to the Central Asian genus Azhdarcho but much younger in age and with the anatomical differences discussed below.

EME VP 312 can be distinguished from the North African Phosphatodraco mauritanicus Pereda-Suberbiola et al., 2003, from the upper Maastrichtian of Ouled Abdoun because this Moroccan taxon has a vestigial neural spine that runs parallel to its long axis [35] . The much larger Arambourgiania is different because this taxon has a neural canal smaller than the lateral pneumatic foramina, posteriorly converging dorso-lateral parasagittal carinae, and small and robust prezygapophyseal pedicles [36] .

In comparison with Asian azhdarchids, the similarly-sized Azhdarcho lancicollis Nessov, 1984 from the Turonian-Coniacian of Uzbekistan [33] nevertheless differs from EME VP 312 in its laterally constricted corpus and reduced hypapophyses that protrude beyond the pre-exapophyseal surface. Aralazhdarcho bostobonensis Averianov, 2007, from the upper Santonian-lower Campanian of Kazakhstan, is also different because it has extremely reduced lateral pneumatic foramina, larger cotylae, smaller prezygapophyses and a well-developed parasagittal carina [34] . Volgadraco bogolubovi Averianov et al., 2008 from the lower Campanian of the Saratov region (Russia) can be distinguished from EME VP 312 because of its comparatively short prezygapophyses, a large central pneumatic foramen above the neural canal, a short but well-expressed hypapophysis and a prominent parasagittal carina that connects the pre- and postzygapophyses.

Compared to other known European Cretaceous fossils, EME VP 312 differs from the indeterminate azhdarchid cervicals described from Valencia [30] as these Spanish specimens are much larger in size, lack parasagittal carinae and have well-developed hypapophyses [30] ). EME VP 312 is very different to the small azhdarchid cervical known from the lower Maastrichtian of Cruzy, Southern France [31] ; this French specimen has short and robust prezygapophyseal pedicles, a diamond-shaped cross-section and a moderately concave triangular cotyle that has a ventral rim projected anteriorly to the hypapophysis [31] . Vertebrae of EME VP 312 can be distinguished from specimens (c.f. Bakonydraco galaczy) collected from the Santonian at Iharkut, Hungary, because of their smaller, ovoid cotylae and enlarged hypapophyses [32] (unpublished specimens in the Magyar Természettudományi Múzeum, Budapest, Hungary (MTM). We note that there are currently no overlapping elements between EME VP 312 and specimens referred to the giant-sized Haţeg azhdarchid Hatzegopteryx thambema [9] .

Although relatively common in the Cretaceous fossil record, azhdarchid pterosaurs are typically represented by isolated remains. We compared EME VP 312 to other azhdarchid specimens for which overlapping elements are known. To date, most described specimens have been assumed to belong to a group of mid-sized and moderately long-necked azhdarchids, apparently the most common morphotype, in contrast to the more rarely recorded large to gigantic-sized very long-necked morph.

The new taxon is diagnosed by the following proposed autapomorphies (which will, of course, be subject to test by later phylogenetic analysis): (1) Length of cervical three ca. 75% of cervical four ( Table 1 ) (the same vertebral ratios in Zhejiangopterus and Quetzalcoatlus are closer to 60%; M. Witton, pers. comm. 2012); (2) Well-developed and elongated prezygapophyseal pedicles on cervical vertebrae that enclose an angle of 30 degrees with respect to the long axis; (3) Well-developed preexapophysis with an anteriorly oriented articular facet, separated from the external prezygapophyseal diapophysis via a deep sulcus;(4) Lateral pneumatic foramina small and situated lateroventrally with respect to the neural canal.

Eurazhdarcho (urn:lsid:zoobank.org:pub:E1E2577C-85A2-4032-B0DD-FB4FCEAD82DB), combination of Europe and Azhdarcho (which comes from the Uzbek word azhdarkho, the name of a dragon in Uzbek mythology employed here to indicate European occurrence and close similarity with the Central Asiatic genus Azhdarcho Nessov, 1984; langendorfensis (urn:lsid:zoobank.org:act:1CE0CDD8-3DC7-4CED-B47B-E59D1B402936), derived from Langendorf, the ancient Transylvanian-German name of Lancrăm village, the Type locality.

Numbered labels are as follows: cervical vertebrae (1, 2 and 10); third (#2) and fourth (#1) cervicals; right wing metacarpal four (# 3); incomplete right metacarpal three (# 4); proximal half of first right wing phalanx (# 5); portion of distal diaphysis of the second smaller wing phalanx (# 6); distal manual phalanx (# 7), and; several indeterminate fragmentary bones (# 8, 9, 11–15) some perhaps pertaining to additional manual phalanges and/or small metacarpals. As part of the associated skeletal elements of EME VP 312 (# 10–15) are now stored in the UBB collection (subsequent to collection; excavation B), closer examination for this project was not possible.

Description

EME VP 312 comprises closely associated and semi-articulated portions of the skeleton of a medium-sized azhdarchid pterosaur (Figures 4–14). The specimen consists of (at least) three anterior cervical vertebrae, a right wing metacarpal IV, an incomplete right metacarpal III, the proximal half of the first right wing phalanx, part of the distal diaphysis of the second smaller wing phalanx, a distal manual phalanx and several other fragmentary bones (Figures 4, 5). Some of these additional bones may represent manual phalanges and/or small metacarpals. Although not directly articulated, all the bones of EME VP 312 were found in close association: in the absence of any evidence to the contrary, we regard these elements as belonging to a single individual (Figures 4, 5). This is also consistent with bone proportions (Table 1).

The preservation of EME VP 312 is not exceptional and the cortical bone of several elements has been partially lost, leaving just impressions of internal bone molds. When actual bone is present, it is well-preserved (Figure 5) and in a similar condition to that reported in other pterosaurs (e.g., [37], [38]). Although some portions of individual elements have been crushed, they are not extremely flattened as is the case for many pterosaurs, notably similarly-aged specimens from the Niobrara Formation in Kansas, USA [37] and from the Jehol Group and older deposits of China (e.g., [39], [40]). Some elements of EME VP 312 are preserved in three dimensions, especially the cervicals, and this allows clear description of their morphology (Figure 5). They do not approach the condition, however, reported for pterosaurs from the well known Romualdo Formation (Santana Group) (Albian), Araripe Basin, Brazil (e.g., [41], [42]).

The remains of at least three cervical vertebrae (Figures 6–8) are identified here as part of EME VP 312. A fourth fragmentary bone (? in Figure 5) might also turn out to be a cervical element, but it consists of only its middle portion and is too compressed to allow a definitive interpretation.

The best-preserved cervical vertebra of EME VP 312/1 is an elongate and gracile element that we interpret as cervical four (Figure 6). It has expanded pre- and postzygapophyseal areas and is relatively uncrushed, preserving most of the cortical bone surface and, anteriorly, the internal mold of the neural canal. It consists of the partial anterior articular region, most of the corpus (cortex slightly damaged anteroventrally, posterodorsally and caudoventrally) and both (slightly damaged) postzygapophyses (Figure 6). The preserved minimum elongation ratio of this element is ∼3,0 while the maximum elongation ratio is ∼6,0 (Table 1). EME VP 312/1 also has well-developed and elongated prezygapophyseal pedicles that enclose an angle of 30 degrees with respect to the long axis, comparatively large preexapophyses with anteriomedially oriented articular facets that are separated from the prezygapophyseal tubercles by deep and wide ventral sulci. This latter feature suggests the remnant of an extremely reduced cervical rib similar to that observed in some other azhdarchids [43]. There are also large anteromedially oriented semicircular to oval prezygapophyseal facets with anteroposteriorly convex and lateromedially concave articular surfaces (Figure 6). The neural canal of EME VP 312/1 is preserved as a prominent internal mold positioned at mid-height between the preexapophyses. The corpus of this vertebrae is elongate and with a dorsoventrally sub-oval cross-section and parallel lateral margins along its length (Figure 6). Anterodorsally along the spine, the corpus is slightly concave and becomes convex posteriorly; ventrally, the surface of the corpus is slightly convex and lacks hypaphophyses. There is a low and blade-like neural spine (Figure 6) (except anteriorly where this is broken) that is relatively elevated and divided into anterior and posterior ridges separated with an elongate low gap. The anterior section of this spine, slightly truncated posteriorly, comprises 30 percent of the whole vertebral length.

Another cervical vertebra (EME VP 312/2) is compressed dorsoventrally and is distorted on its right side. We interpret this element as cervical three (Figure 7): it consists of the posterior portion of the centrum (the posterior articular region is damaged), the right postzygapophysis, a small part of the left postzygapophyseal facet and partial condyle and most of the corpus with a low dorsal neural spine. The element is moderately elongated with a preserved centrum length of 86.5 mm (thus, total estimated length 90 mm) The maximum width of the central portion of this vertebra is 22 mm, giving a maximum elongation ratio close to 4.0(Table 1). The centrum of EME VP 312/2 is hollow and has an average bone thickness of ca. 1 mm. It is slightly higher than wide and lacks lateral pneumatic foramina (Figure 7). The dorsal surface of this element is slightly convex and gives the whole centrum a tube-like outline while a small groove is present on the middle portion of the dorsal rim of the cotyle, dorsal to the neural channel. Poor preservation means that it is not possible to determine the presence of a lateral pneumatic foramen on either side of the neural canal, as is present in some other azhdarchid [26], [43], [44] and tapejarid [45] azhdarchoids.

The anterior articular region of this vertebra, although slightly crushed (2.9 times wider than high), nevertheless bears some distinctive features (Figure 7): well-developed and elongated prezygapophyseal pedicles that enclose an angle of 35 degrees with respect to the long axis; a relatively wide and low cotyle with a small lateral accessory articular surface dorsally and below the neural canal; a well-developed preexapophysis with an anteriorly oriented articular facet, separated from the external prezygapophyseal diapophysis via a deep sulcus; comparatively large anteroposteriorly elongated and slightly convex oval prezygapophyseal facets that are anteromedially oriented. The relatively small neural canal opening of EME VP 312/2 is positioned immediately under the sharp and well-developed interzygapophyseal ridge, while the lateral pneumatic foramina are smaller and are situated lateroventrally (Figure 7). At interprezygapophyseal level, the neural spine and hypapophyses dorsally and ventrally are completely reduced, thus the anterior ventral surface of the corpus is flat and slightly convex (Figure 7).

The prezygapophyseal articulations between EME VP 312/1 and 312/2 match perfectly (Figure 8) and further corroborate our anatomical identifications. Based on the morphology of these articular surfaces, it is also noteworthy that little or no lateral and limited vertical movement would have been possible at the junction between cervicals 3 and 4 (no more than 20 to 30 degrees). However, the shape of the prezygapophyseal articulation on the third cervical indicates greater mobility at the atlas-axis/cervical 3 junction, up to 45 degrees vertically. These are in agreement with similar values calculated for a mid-sized azhdarchid (?Azhdarcho) from the Cenomanian-Santonian of Burkhant, Mongolia [46].

The third identifiable cervical vertebrae that comprises EME VP 312 (labelled 10 on Figure 4) is now housed in the UBB collection and is inaccessible to us. It consists of the posterior portion of a centrum with left postzygapophysis. All three vertebrae comprising EME VP 312 were mostly likely articulated and belonging to the anterior part of the neck: most likely the atlas-axis and cervicals three and four (Figure 4).

In comparison with other described azhdarchid taxa, the preserved mid-cervical elements of EME VP 312 are extremely elongate and bear less reduced neural spines, especially cervical three (Figures 6–8). The vertebrae of EME VP 312 also have low neural arches that are confluent with their respective centra: superficially, they form tubes with reduced, or absent, cervical ribs. Of these characters, the first three are proposed synapomorphies of Azhdarchidae [27], [29] while the absence of marked pneumatopores on the cervical centra may represent an additional autapomorphy (or intraspecifically variable feature) of this new medium-sized Romanian taxon (see Discussion). The cervicals of EME VP 312 are also similar to those from the Upper Cretaceous (Santonian) Csehbánya Formation that outcrops in the Bakony Mountains, Hungary. Several elements (some still unpublished, Attila Ösi pers. comm. 2011) were found associated with the Hungarian azhdarchid Bakonydraco galaczi and might be referable to this species [32]. For example, EME VP 312/1 cervical four has a length/minimum width ratio that is very similar to MTM Gyn/448, also regarded as a likely fourth cervical element (Attila Ösi pers. comm. 2011). It is also noteworthy that in MTM Gyn/448 the prezygapophyseal pedicels are shorter, much more robust and have a different enclosure angle with respect to their long axes than is the case in EME VP 312.

The cervicals of EME VP 312 also share the presence of well-developed hypapophyses and parasagittal carinae with described material of Aralazhdarcho bostobonensis from the late Santonian-early Campanian of Kazakhstan [34]. The Romanian specimen, however, differs in the possession of extremely reduced lateral pneumatic foramina, a larger cotyle and smaller prezygapophyses. A low neural spine is also seen in the North American azhdarchid Montanazhdarcho minor [48], [49] from the Campanian Two Medicine Formation, Montana, where the spine is even shorter and lower than in EME VP 312.

An additional, similar-sized azhdarchid, Volgadraco bogolubovi [50], is known from the lower Campanian of the Saratov region, Russia. This species was described on the basis of scattered remains that apparently belong to several individuals, including a third cervical. If this cervical of Volgadraco is correctly identified, it differs from EME VP 312 in being comparatively shorter, in possessing an anteriorly high neural arch, a large central pneumatic foramen located above the neural canal, small pneumatic foramina on the lateral side of its corpus (although this may reflect individual variation), a short but prominent hypapophysis, and a prominent parasagittal carina connecting the pre- and postzygapophyses. However, we suggest that the length of this element in Volgadraco, combined both with the presence of a dorsal pneumatic foramen located above the neural canal and a well-expressed hypapophysis, indicate that this is a more posterior cervical vertebra than described (see, for example, the condition in Azhdarcho).

EME VP 312 also comprises at least 6 wing-bones (312/3-8) but, due to their fragility, most of these are heavily crushed and/or distorted and fragmented (Figures 5, 9–11). Other elements (numbered 12–15 in Figure 4) may also represent small metacarpals and/or phalanges.

Of these preserved elongate elements, EME VP 312/3 is the longest (Table 1) and best preserved (Figure 10). We interpret this element as the fourth right wing metacarpal (Figure 10): it is almost complete (only the proximal epiphysis is missing), very elongate and gracile, and most of its cortex is preserved, though heavily crushed antero-posteriorly. The distal articular region is also distorted and shifted about 45–50 degrees laterally. The proximal region of the shaft close to the articulation in EME VP 312/3 is subrectangular, less compressed and has a longitudinal groove and a small subcircular depression (Figure 10). The diaphysis is straight but compressed (reconstructed midshaft diameter ∼11 mm), and narrows distally. The cortex has an average thickness of 1 mm, with smooth internal surface on the proximal 2/3, and has well-expressed trabecular internal structure toward its distal end. The intercondylar groove on the distal end is deep, without a rounded median crest or ridge: a similar condition is seen in Azhdarcho and Montanazhdarcho [48], [49].The distal-most part of the shaft is completely flattened and has two more-or-less circular (possible) puncture marks.

Discovered lying parallel to the first wing phalanx, a smaller long bone is interpreted here as the third metacarpal (EME VP 312/4) (Figures 4, 11). Only about two-thirds of this bone remains (Table 1): it has a diaphysis with a subtriangular to suboval cross-section that narrows proximally and becomes flared distally. The distal epiphysis is wide and triangular in shape and has a slightly convex articular surface that is partially damaged.

The second longest bone preserved as part of this specimen (EME VP 312/5) we interpret to be the first phalanx of the fourth wing finger (Figure 12) as it is preserved in semi-articulation with metacarpal four (Figure 4). About two-thirds of this bone is preserved (the distal region is missing). It is dorsoventrally crushed and most of the external cortical bone is missing (Figure 12). The proximal articular region of EME VP 312/5 is damaged, but a proximally prominent triangular structure, similar to an extensor tendinal process, is preserved (Figure 12). If this interpretation is correct, the specimen represents a relatively mature individual [51], [52]: Complete ossification and fusion of this region is seen in later ontogenetic stages [51], [52]. The articular surface of EME VP 312/5 is also badly preserved but the ventral articular cotyle is better expressed: the diaphysis is dorsoventrally compressed and hollow. The average bone thickness at the diaphysis is ca. 1 mm but reaches a maximum of ca. 3 mm proximally. This bone also has an oval transverse section with the middle part of its diaphysis narrowing toward its distal end (Figure 12).

EME VP 312/6 is a small shaft fragment (length, 52 mm; average width, 8 mm) that we interpret as being from part of the mid-distal diaphysis of a smaller phalanx, most likely the second phalanx of wing finger four (Figure 13). This element has the typical (inverted) “T” shaped ventral transverse cross section that is seen in azhdarchid [47], [48] and tapejarid (A. Kellner, pers. obs. 2011) pterosaurs. The strong ventral ridge of this element, placed centrally along the shaft and becoming slightly shifted posteriorly towards the proximal end, is reminiscent of the condition seen in Azhdarcho lancicollis [33], [50].

EME VP 312/7 is a small bone that was found in close association with the metacarpals (length, 15 mm; proximal depth, 5 mm): it is interpreted here as a distal manual phalanx (Figure 14) that has a subrectangular, widened proximal epiphysis and a slightly curved, distally crushed diaphysis with an oval cross section. Proximally, the articular surface is concave but damaged: although apparently lacking a lateral or latero-ventral pneumatic foramen, this bone is similar to the distal manual phalanges of Azhdarcho from the Turonian of Uzbekistan [33], particularly in the size and shape of its diaphysis.

EME VP 312/8, is a small elongate bone fragment, tentatively interpreted here to be the distal section of the terminal wing phalanx. This small bone has a low triangular-to-oval cross section (it lacks a ventral ridge) and a comparatively thick cortex (ca. 1.0 mm). Similar bone fragments have been described from the Campanian-Maastrichtian of Campagne-sur-Aude in southern France [51], [54] and from the Santonian of Iharkut, Hungary [47]. However, in Azhdarcho lancicollis, the fourth wing phalanx is rod-like, has a triangular cross-section and, distally, lacks a ventral ridge [33].