![First Tapejarid Pterosaur from the Wessex Formation (Wealden Group](https://data.docslib.org/img/3a60ab92a6e30910dab9bd827208bcff-1.webp)
1 1 First tapejarid pterosaur from the Wessex Formation 2 (Wealden Group: Lower Cretaceous, Barremian) of the 3 United Kingdom 4 5 David M. Martill1*, Mick Green2, Roy Smith1, Megan Jacobs1, John 6 Winch3 7 1School of the Environment, Geography and Geological Sciences, University of Portsmouth, Burnaby Road, 8 Portsmouth PO1 3QL 9 21 Coastguard Cottages, Military Road, Brighstone, Isle of Wight, PO30 4DA, UK 10 3Seajade, 7 West Lake Avenue, Lake, Isle of Wight, POX 36 9NJ, UK 11 *corresponding author 12 13 Abstract. 14 15 An isolated, partial premaxilla from the Lower Cretaceous (Barremian) Wessex Formation of 16 Yaverland, Isle of Wight, UK is identified as pterosaurian on account of its overall 17 morphology and thin bone walls. It is regarded as a tapejarid on account of it unique down- 18 turned tip with a unique pattern of slit-like foramina on its occlusal surface, while a 19 combination of sensory foramina and lateral outline identify it as a new genus and species. 2 20 The downturn of the occlusal margin lies beyond the anterior margin of the nasoantorbital 21 fenestra suggesting affinities with Sinopterus from China rather than South American 22 tapejarids such as Tapejara, Tupandactylus and Caiuajara. This specimen is the first record 23 of Tapejaridae in the Wessex Formation, and is amongst the oldest record of the 24 Tapejaridae outside of China. 25 26 Keywords: Pterosauria; Tapejaridae; Wealden Group; Early Cretaceous; Isle of Wight; 27 England 28 29 30 1. Introduction 31 Tapejarids are remarkable looking members of the Pterosauria that often possess large, highly 32 elaborate soft tissue head crests supported by osseous extensions of the parietals and squamosals 33 posteriorly and an extra osseous spin anteriorly (Frey et al., 2003). They are all the more prominent 34 because of a unique conspicuously downturned anterior rostrum and mandible (Kellner, 2004; 35 Wellnhofer and Kellner, 1991). First described from the Lower cretaceous of South America (Kellner, 36 2004; Wellnhofer and Kellner, 1991) the Tapejaridae have subsequently been reported from China 37 (Wang and Zhou, 2003; Li et al., 2003; Lü et al., 2005, 2016), Europe (Vullo, et al., 2012), and in Africa 38 from Morocco (Wellnhofer and Buffetaut, 2003; Martill et al., 2020) and an unsubstantiated claim 39 from Niger (Blackburn and Sereno, 2002). 40 Their remains occur frequently in the Araripe Basin of northeast Brazil in both the Crato Formation 41 Lagerstätte (Sayão and Kellner, 2006; Unwin and Martill, 2008; Pinheiro, 2011; Pegas et al., 2016) 42 and Santana Formation Lagerstätte (Kellner, 2013; Martill and Brito, 2017) where excellent 3 43 articulated tapejarid skeletons are reported, often with soft tissue preservation (Frey et al., 2003), in 44 three-dimensions (e.g. Vila Nova et al., 2015) and even examples of multiple specimens in a single 45 concretion (Eck et al., 2011). Elsewhere in Brazil tapejarids have been reported in mass death 46 assemblages forming a pterosaur bone bed in the mid-Late Cretaceous Caiuá Group (Manzig et al., 47 2014). The Jiufotang Formation of China also yields, with some frequency, complete and fully 48 articulated tapejarid remains (Lü and Yuan, 2005; Lü et al., 2005, 2016; Wang et al., 2008). 49 Elsewhere, however, tapejarid remains are exceedingly rare, with only fragmentary material 50 reported from North Africa (Wellnhofer and Buffetaut, 2003; Martill et al., 2020) and Europe. 51 The Brazilian tapejarids are generally dated as Aptian (Crato Formation) and possibly Albian (Santana 52 Formation), while the Chinese material is regarded as Aptian (Jiufotang Formation) and Barremian 53 (Yixian Formation) age (Pan et al., 2013). The enigmatic Bakonydraco from the Turonian of Hungary, 54 originally described as an azhdarchid (Ősi et al., 2005, 2011) has, in some analyses been found as a 55 tapejarid (Andres et al., 2014; Longrich et al., 2018). Should Bakonydraco be a tapejarid, the group 56 has a range spanning almost 40 million years from the Barremian to the Turonian (Barrett et al., 57 2008). The African tapejarid, Afrotapejara Martill, et al., 2020 from the Kem Kem Group of south 58 east Morocco is likely of late Albian age (Ibrahim et al., 2020). 59 60 2. Locality and stratigraphy 61 The specimen (IWCSM. 2020. 401) described here was collected by one of the authors (JW) from a 62 plant debris bed (see Sweetman and Insole, 2010) exposed on the wave cut platform at Yaverland, 63 near Sandown on the Isle of Wight (Fig. 1) (National Grid Reference SZ 61989 85256). At this locality 64 gently dipping (~ 10°) Lower Cretaceous strata of the Wealden Group comprising the upper part of 65 the Wessex Formation and the overlying Vectis Formation form soft, slump-prone cliffs that are daily 66 washed by the high tide. The locality has become well known for an abundance of vertebrate fossils, 67 especially from the plant debris bed horizons of the Wessex Formation (Sweetman and Insole, 2010). 4 68 In particular, the locality has yielded dinosaurs (Martill and Naish, 2001) and pterosaurs (Steel et al., 69 2005) that are unique to the locality (Yaverlandia and Caulkicephalus respectively). The specimen 70 was found in the highest plant debris bed before the Wessex Formation passes up into the Cowleaze 71 Chine Member of the Vectis Formation (bed 38 of Radley, 1994) (Fig. 1). This upper part of the 72 Wessex Formation is considered to be of Barremian age (Batten, 2011). 73 74 3. Material and Methods 75 The new specimen described here (Fig. 2) has been prepared using a fine dental pick, with some 76 concretionary pyrite removed using an air pen. The specimen has been repaired using a 77 cyanoacrylate adhesive with accelerator. Linear measurements were obtained using digital calipers, 78 and CorelDRAW graphics suite software for determining angular measurements. Digital photography 79 and image stacking using CombineZP software was employed for image production. 80 Photomicrographs were taken on a Leica EZ4W light microscope. 81 The following museum abbreviations are used: AMNH, American Museum of Natural History, New 82 York, USA; CD, Desiree Collection, Rio de Janeiro, Brazil; CP.V, Centro Paleontológico (CENPALEO), 83 Universidade do Contestado, Mafra, Santa Catarina, Brazil; FSAC, Faculté de Sciences, Laboratoire de 84 Géosciences, Université Hassan II, Casablanca, Morocco; GMN, Geological Museum, Nanjing, China; 85 IVPP, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing; JPM, Jinzhou 86 Palaeontological Museum, Jinzhou City, Liaoning Province, China; MCT, Paleontological Collections 87 of the Museu de Ciências da Terra (Departamento Nacional da Produção Mineral), Rio de Janeiro, 88 Brazil; MIWG, Museum of Isle of Wight Geology (Dinosaur Isle Visitor Centre), Sandown, Isle of 89 Wight, England; MN, Museu Nacional, Universidade Federal do Rio de Janeiro, Brazil; SAO/UOSG: 90 Collection Urs Oberli, St. Gallen, Switzerland; SMNK, Staatliches Museum für Naturkunde, Karlsruhe, 91 Erbprinzenstrasse 13, Karlsruhe, Germany; XHPM, Dalian Xinghai Palaeontological Bio Expo 92 Museum; ZMNH, Zhejiang Museum of Natural History, Hangzhou, China. 5 93 4. Systematic Palaeontology 94 95 Pterosauria Kaup, 1834 96 Monofenestrata Lü et al., 2010 97 Pterodactyloidea Plieninger, 1901 98 Azhdarchoidea Nesov, 1984 sensu Unwin, 1992 99 Tapejaramorpha Andres, Clark, Xu, 2014 100 Tapejaridae Kellner, 1989 101 Wightia gen. nov 102 Type and only species (see below). 103 Etymology. Wightia, pertaining to the Isle of Wight, southern England from where the type species 104 was discovered 105 Wightia declivirostris sp. nov. 106 Etymology. Declivi (L.) = slanting, and rostris (L.) = beak - in combination pertaining to the downward 107 slanting beak tip of this taxon. 108 Holotype. IWCMS. 2020. 401 (Figs 2, 3, 4, 5). 109 Type locality. Yaverland, Sandown, Isle of Wight, United Kingdom. 110 Type stratum. Wessex Formation (Lower Cretaceous, Barremian) (See Radley 1994). 111 Diagnosis. Tapejarid with premaxilla in which the occlusal (palatal) surface has only a few small 112 elongate foramina and a single row of widely spaced (~ 1 per 10 mm) foramina on the lateral margin 113 very close to the ventral border. A downturn angle of ~12°. 6 114 115 5. Description and comparisons 116 5.1 Osteological description 117 Specimen IWCMS. 2020. 401 comprises fused partial premaxillae of both sides anterior to the 118 nasoantorbital fenestra but lacking the distal tip. The specimen is partially crushed, but is three- 119 dimensional posteriorly and seems laterally compressed in caudal view. The lateral surfaces are 120 somewhat brecciated (Fig. 5A) with spaces between, showing that the specimen has expanded 121 slightly due to minor displacement between fragments. This means that the fossils looks slightly 122 larger than it would have in vivo (Fig. 5C). The specimen displays the downturned occlusal margin of 123 the premaxilla that characterises the Tapejaridae, with a down turn angle of ~12° (Fig. 5C). The 124 lateral margins are smooth and there are small (less than 1 mm diameter) foramina lying just dorsal 125 of the occlusal margin (ventral border) (Fig. 5B). The occlusal surface is gently sulcate with rounded 126 borders, and displays just a few small, oval foramina (Fig. 4A, B) arranged in irregular clusters of 127 three or four foramina. The dorsal surface is smoothly rounded and defines a slightly concave profile 128 in lateral view (Fig. 2). The bone wall is exceptionally thin, with a maximum thickness of 0.61 mm 129 with no obvious thickening in the corners (Fig. 2E, F). Under the microscope, the bone of the lateral 130 margins is covered with numerous closely-spaced micro-pores (3A, B) some of which are circular or 131 slightly oval, or are more elongate and slightly meandering anteriorly and dorsally, whereas more 132 ventral and posterior surfaces have a ripple-like surface texture (Fig. 3D). Projection of the dorsal 133 and ventral margins until they meet to form a tip suggests this is a long-snouted tapejarid (Fig.
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