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A new pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco.

Ibrahim N, Unwin DM, Martill DM, Baidder L, Zouhri S - PLoS ONE (2010)

Bottom Line: We assign additional fragmentary jaw remains, some of which have been tentatively identified as azhdarchid and pteranodontid, to this new taxon which is distinguished from other azhdarchids by a remarkably straight, elongate, lance-shaped mandibular symphysis that bears a pronounced dorsal eminence near the posterior end of its dorsal (occlusal) surface.Most remains, including the holotype, represent individuals of approximately three to four meters in wingspan, but a fragment of a large cervical vertebra, that probably also belongs to A. saharica, suggests that wingspans of six meters were achieved in this species.This, the relatively large size achieved by Alanqa, and the additional evidence of variable jaw morphology in azhdarchids provided by this taxon, indicates a longer and more complex history for this clade than previously suspected.

View Article: PubMed Central - PubMed

Affiliation: School of Medicine and Medical Science, University College Dublin, Dublin, Republic of Ireland. Nizar.Ibrahim@ucd.ie

ABSTRACT
The Kem Kem beds in South Eastern Morocco contain a rich early Upper (or possibly late Lower) Cretaceous vertebrate assemblage. Fragmentary remains, predominantly teeth and jaw tips, represent several kinds of pterosaur although only one species, the ornithocheirid Coloborhynchus moroccensis, has been named. Here, we describe a new azhdarchid pterosaur, Alanqa saharica nov. gen. nov. sp., based on an almost complete well preserved mandibular symphysis from Aferdou N'Chaft. We assign additional fragmentary jaw remains, some of which have been tentatively identified as azhdarchid and pteranodontid, to this new taxon which is distinguished from other azhdarchids by a remarkably straight, elongate, lance-shaped mandibular symphysis that bears a pronounced dorsal eminence near the posterior end of its dorsal (occlusal) surface. Most remains, including the holotype, represent individuals of approximately three to four meters in wingspan, but a fragment of a large cervical vertebra, that probably also belongs to A. saharica, suggests that wingspans of six meters were achieved in this species. The Kem Kem beds have yielded the most diverse pterosaur assemblage yet reported from Africa and provide the first clear evidence for the presence of azhdarchids in Gondwana at the start of the Late Cretaceous. This, the relatively large size achieved by Alanqa, and the additional evidence of variable jaw morphology in azhdarchids provided by this taxon, indicates a longer and more complex history for this clade than previously suspected.

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Reconstructed jaws of Alanqa saharica compared to other azhdarchids.A) Holotype specimen (mandibular symphysis) of Alanqa saharica nov gen. nov sp. (FSAC-KK 26) matched with one of the referred rostra, BSP 1993 IX 338. B) Skull outline of the azhdarchid Zhejiangopterus linhaiensis, modified from Unwin and Lü [58] and Witton and Naish [65]. C) Lower jaw of Quetzalcoalus sp., redrawn from Kellner and Langston, specimen TMM 42161-2 [45].
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pone-0010875-g004: Reconstructed jaws of Alanqa saharica compared to other azhdarchids.A) Holotype specimen (mandibular symphysis) of Alanqa saharica nov gen. nov sp. (FSAC-KK 26) matched with one of the referred rostra, BSP 1993 IX 338. B) Skull outline of the azhdarchid Zhejiangopterus linhaiensis, modified from Unwin and Lü [58] and Witton and Naish [65]. C) Lower jaw of Quetzalcoalus sp., redrawn from Kellner and Langston, specimen TMM 42161-2 [45].

Mentions: All five jaw fragments assigned here to Alanqa saharica are well preserved, uncrushed and, unlike the vast majority of pterosaur fossils, retain their original three dimensional shape. The holotype mandibular symphysis (FSAC-KK 26, Figures 2 and 3, Table 2), identified as such by its similarity to the mandibular symphysis of Quetzalcoatlus sp. ([45] Figure 4A, 4C), was preserved in a soft crumbly sandstone that, apart from small isolated patches that strongly adhere to the bone surface, was easily removed. The holotype consists of three contiguous orange-brown fragments with a combined length of 344 mm. The anterior tip of the symphysis is missing: extending the dorsal and ventral jaw margins, or the lateral margins of the jaw, forward to the point where they meet, which is consistent with jaw shape in other azhdarchids such as Zhejiangopterus linhaiensis [46] and Quetzalcoatlus sp. [45] indicates that the length of the missing portion may have been up to 80 mm. Much of the ventral half of the intermediate fragment is broken away, especially anteriorly where a small part of the palatal surface is also missing. The symphysis appears to have fractured at its posterior end where the mandible diverged into separate rami.


A new pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco.

Ibrahim N, Unwin DM, Martill DM, Baidder L, Zouhri S - PLoS ONE (2010)

Reconstructed jaws of Alanqa saharica compared to other azhdarchids.A) Holotype specimen (mandibular symphysis) of Alanqa saharica nov gen. nov sp. (FSAC-KK 26) matched with one of the referred rostra, BSP 1993 IX 338. B) Skull outline of the azhdarchid Zhejiangopterus linhaiensis, modified from Unwin and Lü [58] and Witton and Naish [65]. C) Lower jaw of Quetzalcoalus sp., redrawn from Kellner and Langston, specimen TMM 42161-2 [45].
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2877115&req=5

pone-0010875-g004: Reconstructed jaws of Alanqa saharica compared to other azhdarchids.A) Holotype specimen (mandibular symphysis) of Alanqa saharica nov gen. nov sp. (FSAC-KK 26) matched with one of the referred rostra, BSP 1993 IX 338. B) Skull outline of the azhdarchid Zhejiangopterus linhaiensis, modified from Unwin and Lü [58] and Witton and Naish [65]. C) Lower jaw of Quetzalcoalus sp., redrawn from Kellner and Langston, specimen TMM 42161-2 [45].
Mentions: All five jaw fragments assigned here to Alanqa saharica are well preserved, uncrushed and, unlike the vast majority of pterosaur fossils, retain their original three dimensional shape. The holotype mandibular symphysis (FSAC-KK 26, Figures 2 and 3, Table 2), identified as such by its similarity to the mandibular symphysis of Quetzalcoatlus sp. ([45] Figure 4A, 4C), was preserved in a soft crumbly sandstone that, apart from small isolated patches that strongly adhere to the bone surface, was easily removed. The holotype consists of three contiguous orange-brown fragments with a combined length of 344 mm. The anterior tip of the symphysis is missing: extending the dorsal and ventral jaw margins, or the lateral margins of the jaw, forward to the point where they meet, which is consistent with jaw shape in other azhdarchids such as Zhejiangopterus linhaiensis [46] and Quetzalcoatlus sp. [45] indicates that the length of the missing portion may have been up to 80 mm. Much of the ventral half of the intermediate fragment is broken away, especially anteriorly where a small part of the palatal surface is also missing. The symphysis appears to have fractured at its posterior end where the mandible diverged into separate rami.

Bottom Line: We assign additional fragmentary jaw remains, some of which have been tentatively identified as azhdarchid and pteranodontid, to this new taxon which is distinguished from other azhdarchids by a remarkably straight, elongate, lance-shaped mandibular symphysis that bears a pronounced dorsal eminence near the posterior end of its dorsal (occlusal) surface.Most remains, including the holotype, represent individuals of approximately three to four meters in wingspan, but a fragment of a large cervical vertebra, that probably also belongs to A. saharica, suggests that wingspans of six meters were achieved in this species.This, the relatively large size achieved by Alanqa, and the additional evidence of variable jaw morphology in azhdarchids provided by this taxon, indicates a longer and more complex history for this clade than previously suspected.

View Article: PubMed Central - PubMed

Affiliation: School of Medicine and Medical Science, University College Dublin, Dublin, Republic of Ireland. Nizar.Ibrahim@ucd.ie

ABSTRACT
The Kem Kem beds in South Eastern Morocco contain a rich early Upper (or possibly late Lower) Cretaceous vertebrate assemblage. Fragmentary remains, predominantly teeth and jaw tips, represent several kinds of pterosaur although only one species, the ornithocheirid Coloborhynchus moroccensis, has been named. Here, we describe a new azhdarchid pterosaur, Alanqa saharica nov. gen. nov. sp., based on an almost complete well preserved mandibular symphysis from Aferdou N'Chaft. We assign additional fragmentary jaw remains, some of which have been tentatively identified as azhdarchid and pteranodontid, to this new taxon which is distinguished from other azhdarchids by a remarkably straight, elongate, lance-shaped mandibular symphysis that bears a pronounced dorsal eminence near the posterior end of its dorsal (occlusal) surface. Most remains, including the holotype, represent individuals of approximately three to four meters in wingspan, but a fragment of a large cervical vertebra, that probably also belongs to A. saharica, suggests that wingspans of six meters were achieved in this species. The Kem Kem beds have yielded the most diverse pterosaur assemblage yet reported from Africa and provide the first clear evidence for the presence of azhdarchids in Gondwana at the start of the Late Cretaceous. This, the relatively large size achieved by Alanqa, and the additional evidence of variable jaw morphology in azhdarchids provided by this taxon, indicates a longer and more complex history for this clade than previously suspected.

Show MeSH
Related in: MedlinePlus