Uktenadactylus rodriguesae, Holgado & Pêgas, 2020

Holgado, Borja & Pêgas, Rodrigo V., 2020, A taxonomic and phylogenetic review of the anhanguerid pterosaur group Coloborhynchinae and the new clade Tropeognathinae, Acta Palaeontologica Polonica 65 (4), pp. 743-761 : 750-751

Uktenadactylus rodriguesae sp. nov.

ZooBank LSID: urn:lsid:zoobank.org:act:229644AA­6FA5­4C4B­988D­863C20197C14

Etymology: In honour of palaeontologist Taissa Rodrigues, in recognition of her herculean work on the taxonomy of anhanguerians and related forms (e.g., Rodrigues and Kellner 2008, 2013; Rodrigues et al. 2015; Pinheiro and Rodrigues 2017).

Holotype: IWCMS 2014.82 , rostrum fragment including tooth positions 1–2 from both sides ( Fig. 5 ).

Type locality: Sudmoor Point, south west coast of the Isle of Wight, England, UK.

Type horizon: Wessex Formation (Barremian), Wealden Group.

Material.— Holotype only.

Diagnosis.— Uktenadactylus species with strongly concave anterodorsal margins of the deltoid facet; a shallow and subcircular (about as high as wide) depression above the first tooth pair; a smooth palatal bulbous projection; and well lateralised second pair of upper alveoli.

Remarks.—This specimen was originally reported as Coloborhynchus sp. by ( Martill 2015), as mentioned above. Such attribution was repeated in subsequent works ( Jacobs et al. 2019, 2020). In the present contribution, we note that IWCMS 2014.82 shares with the holotype of Uktenadactylus wadleighi two features: a round depression on the deltoid facet above the first pair of upper teeth, and a palatal bulbous projection between the second pair of upper teeth. These two features are unique within the Anhangueridae as a whole, and are herein regarded as diagnostic for a genus Uktenadactylus comprising U. wadleighi and U. rodriguesae sp. nov.

Even though the specimen is broken, it is three­dimensional and its anterior and lateral surfaces exhibit well­preserved bone compacta. The new species differs from U. wadleighi in that the dorsolateral margins of the deltoid facet are particularly concave (they are straight in U. wadleighi ), the second pair of upper alveoli is well lateralised (on both sides, despite some distortion), and that the subcircular depression above the first tooth pair is shallower.

Stratigraphic and geographic range.— Type locality and horizon only.

Genus Aerodraco nov.

ZooBank LSID: urn:lsid:zoobank.org:act:436E9D43­EFBC­4A09­AAFD­C9D12D670A39

Type species: Aerodraco sedgwickii gen. et comb. nov.; see below.

Etymology: From Ancient Greek aero, wind and draco, dragon; in reference to the book Dragons of the Air ( Seeley 1901).

Holotype: CAMSM B54422 , an anterior portion of the rostrum displaying the alveoli from the 1st to the 7th pair of teeth ( Fig. 6 ).

Type locality: Cambridge, Cambridgeshire, England, UK.

Type horizon: Cambridge Greensand (Cenomanian; fossils Albian in age).

Material.— Holotype only.

Emended diagnosis.—Coloborhynchine with the following autapomorphies: anterior expansion of the rostrum ends abruptly behind the third pair of alveoli; paired row of neurovascular foramina flanking the palatal ridge; third pair of alveoli larger than in any other coloborhynchine relative to the fourth pair (updated from Rodrigues and Kellner 2013).

Remarks.— Owen (1859) assigned eight rostra to the species Pterodactylus sedgwickii , including the holotype CAMSM B54422, and years later he relocated this species to the genus Coloborhynchus Owen, 1874 due to the first pair of premaxillary teeth projecting forward from the truncate surface at a higher level than the alveolar border. After several decades considered as another species within the Ornithocheirus complex ( Hooley 1914; Wellnhofer 1978; Lee 1994), Unwin (2001) assigned this species to the genus Coloborhynchus , due to the shape of the rostrum as well as the arrangement and size of the teeth being similar to “ Coloborhynchus ” capito , differing exclusively from the latter on the basis of the purported lack of a premaxillary crest. This lead Unwin (2001) to suggest that this difference could represent sexual dimorphism ( Unwin 2001: 208), but did not synonymise the two species waiting for “…a better understanding of the remaining cranial and postcranial anatomy of these taxa and other coloborhynchids” [sic!] ( Unwin 2001). Rodrigues and Kellner (2008: 226) excluded A. sedgwickii from the genus Coloborhynchus , arguing that the anterior end of the rostrum “is round rather than flat” [sic!] as well as a larger spacing between the first and second pairs of alveoli. Posteriorly, Rodrigues and Kellner (2013) tentatively referred it to the genus Camposipterus due to the following combination of features: presence of an expansion of the rostrum, absence of a premaxillary crest, and round rostrum in lateral view. However, none of these features is unique to Camposipterus , and this is why their referral was only tentative ( Rodrigues and Kellner 2013). Although the anterior end of the rostrum is round in lateral view ( Rodrigues and Kellner 2008, 2013), the anterior and lateral margins in occlusal view are straight, similarly to other coloborhynchines and differently from any other anhanguerians. Concerning the premaxillary crest, its absence may remain unclear since the posterodorsal portion of the rostrum is not preserved ( Fig. 6A 5 ). The dorsal surface of the preserved fragment is quite tall and keeled, and thus we regard that an incipient crest was most likely present.

Here, we notice that the CAMSM B54422 bears a distinctive paired row of neurovascular foramina flanking the palatal ridge. This feature is absent in anhanguerids for which the palatal bone surface is well­preserved, such as Uktenadactylus wadleighi , Coloborhynchus clavirostris , Tropeognathus mesembrinus , Maaradactylus kellneri , and Anhanguera sp. AMNH 22555 ( Wellnhofer 1987, 1991; Rodrigues and Kellner 2008, 2013; Bantim et al. 2014; Pinheiro and Rodrigues 2017).

Stratigraphic and geographic range.— Type locality and horizon only.

Figures

Fig.5.Anhanguerid pterosaur Uktenadactylus rodriguesae sp.nov., IWCMS 2014.82, Sudmoor Point, Isle of Wight, England, Barremian.In anterior (A1), left (A2) and right (A3) lateral, posterior (A4), and palatal (A5) views. Photographs by BH.

Fig. 6. Anhanguerid pterosaur Aerodraco sedgwickii gen. et comb. nov., CAMSM B54422, Cambridge, Cambridgeshire, England, Albian. In anterior (A1), left lateral (A2), palatal (A3), right lateral (A4), and dorsal (A5) views. Photographs by BH.