Short-necked azhdarchids? Probably not.

Naish and Witton 2017 bring their insight
to a short, but giant cervical from a Romanian azhdarchid (Fig. 1 inset). They reported, “we discuss a recently discovered giant azhdarchid neck vertebra referable to Hatzegopteryx from the Maastrichtian Sebes Formation of the Transylvanian Basin, Romania. This vertebra, which we consider a cervical VII, is 240 mm long as preserved and almost as wide. Among azhdarchid cervicals, it is remarkable for the thickness of its cortex (46 mm along its ventral wall) and robust proportions.”

Naish and Witton conclude:
“By comparing its dimensions to other giant azhdarchid cervicals and to the more completely known necks of smaller taxa, we argue that Hatzegopteryx had a proportionally short, stocky neck highly resistant to torsion and compression.”

Figure 2. Quetzalcoatlus has a long cervical 7 and a short cervical 8. Naish and Witton consider the Romanian cervical #7, creating a short neck. But see figure 2.

Figure 2. Quetzalcoatlus has a long cervical 7 and a short cervical 8. Naish and Witton consider the Romanian cervical #7, creating a short neck. But see figure 2. The tall neural spine on cervical 8 is speculative and may be absent.

If the Romanian cervical is similar to cervical 7 of Quetzalcoatlus,
(Fig. 1) then the authors’ extrapolation seems reasonable.

Figure 2. Azhdarcho cervicals 7 and 8 are both short, but the anterior cervicals are elongate.

Figure 2. Azhdarcho cervicals 7 and 8 are both short, but the anterior cervicals are elongate. The Romanian cervical may belong to a similar genus, only larger.

However, if similar to the shorter cervical 7 of Azdarcho,
(Fig. 2) then the authors’ extrapolation can only be considered inconclusive. The rest of the cervicals in Azhdarcho are long and slender, matching those of all other clade members. Azhdarcho comes from Uzbekistan, closer to Romania than Quetzalcoatlus (Fig. 1), which comes from Texas.

Naish and Witton suggest,
“This specimen is one of several hinting at greater disparity within Azhdarchidae than previously considered, but is the first to demonstrate such proportional differences within giant taxa.”

Given the anatomy of Azhdarcho,
that conclusion is premature at present. We need to see at least some short anterior cervicals.

Historically, Naish and Witton imagined giant azhdarchids
as world-wide soarers, able to quad launch with folded wings, and terrorizing terrestrial prey like tiny sauropods. All of these fanciful hypotheses have been invalidated, but remain popular with paleoartists.


References
Naish D and Witton MP 2017. Neck biomechanics indicate that giant Transylvanian azhdarchid pterosaurs were short-necked arch predators. PeerJ 5:e2908; DOI 10.7717/peerj.2908

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