2024 has been a great year for new titanosaurs, as we are now on the fifth to be announced and we're still more than three months from the end of the year. For a change of pace, this time we're heading to Europe. Qunkasaura pintiquiniestra, the first new European titanosaur in more than two and a half years, hails from the Lo Hueco site in Spain.
Genus and Species: Qunkasaura pintiquiniestra. The genus name refers to a former Andalusí city, Qunka (Kunka), that was quasi-ancestral to the city of Cuenca. (Pronunciation is not included, but I have to wonder if a "K" sound is intended [or was intended at one point] over the "Kw" that English speakers usually assume when there's a "Qu" involved.) The "-saura" ending is not only the feminine form of "saurus" but also a reference to Antonio Saura, a famous 20th-century Spanish artist associated with Cuenca. The species name links this species to fellow Lo Hueco bonebed titanosaurian denizen Lohuecotitan pandafilandi, as it is also an allusion to "Don Quixote". In this case Queen Pintiquiniestra is a character from one of the chivalric romances that led to Don Quixote becoming, well, Don Quixote (Mocho et al. 2024).
Citation: Mocho, P., F. Escaso, F. Marcos-Fernández, A. Páramo, J. L.
Sanz, D. Vidal, and F. Ortega. 2024.
A Spanish saltasauroid titanosaur reveals Europe as a melting pot of
endemic and immigrant sauropods in the Late Cretaceous. Communications Biology 7: 1016. doi:
https://doi.org/10.1038/s42003-024-06653-0.
(This is one where you really need the supplementary material as well.)
Geography and Stratigraphy: As noted above, the type and only known specimen of Q. pintiquiniestra was found at the Lo Hueco bonebed, which is just west of the town of Fuentes and about 8 km (5 mi) southeast of Cuenca, in the province of the same name in Castilla–La Mancha, east-central Spain. The bonebed is in the Villalba de la Sierra Formation, dated to the late Campanian–early Maastrichtian (Mocho et al. 2024). (Incidentally, Cuenca was one of the filming locations for "The Valley of Gwangi". Cheesy, but I wonder if they have a theropod in need of a name...)
Holotype: Q. pintiquiniestra is based on a partial articulated to associated skeleton collectively cataloged as HUE-EC-04 (Lo Hueco collection at the Museo de Paleontología de Castilla–La Mancha in Cuenca, Spain), but with individual elements getting their own numbers. Bones include a partial neural spine from a posterior cervical, ten dorsals, some dorsal ribs, a sacrum of six fused vertebrae, the first eleven caudals and a middle caudal, a partial right ulna, a partial metacarpal, a nearly complete pelvis, a not-yet-fully-prepared femur, and a right fibula (Mocho et al. 2024).
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| Click to embiggen. Figure 1 in Mocho et al. (2024) (see here for entire original caption) is probably rather more useful than my entire post, since you get the stratigraphy, geography, skeletal reconstruction, and quarry map, but heck. (CC BY-NC-ND 4.0). |
Lo Hueco is noted for multiple partial skeletons of titanosaurs representing at least two taxa, at this point L. pandafilandi and Q. pintiquiniestra. Since we're talking titanosaurs, the door is always open to there being others. There are two significantly different braincase types, and it would not be surprising if there's one for both named species, but this will have to wait for the partial specimens with braincases to be described and assigned. Q. pintiquiniestra is described as "medium to large" (Mocho et al. 2024), although I think that makes the most sense in a European context; Q. pintiquiniestra does all right for a European titanosaur, but would be just another sauropod next to one of the giant titanosaurs.
Anatomically Q. pintiquiniestra is quirky. The neural spines of the dorsals tend to be long and angled strongly posteriorly until just in front of the hip, where they become much more vertical and for some reason much wider than long (6 times wider, to be exact). In the sacrum, the neural spines are fused into one unit with no gaps, fairly tall as these things go in titanosaurs, and incorporate an ossified ligament running along the top. The first caudal is biconvex, and the rest of the string is procoelous, with the ball strongly shifted to the upper part of the posterior end of the centrum. The prezygapophyses (the pair of processes on the front of the neural arch that articulate with the vertebra in front) do an aeolosaur-like anterior stretch, paired with a neural spine that's more of a elliptical flange pointing anterior-dorsally by the end of the preserved string. The tail also seems to droop noticeably coming off the pelvis. (It is not an unknown thing for titanosaur tails to have a downward turn, but it usually comes farther along.)
The pelvis, which is articulated and mostly complete (except for the right ilium), is also odd. The ilia flare anteriorly, like most good titanosaurs, but they also do it over a compressed horizontal distance (in side view, they look kind of like they've been squeezed fore-aft and allowed to expand up and down to compensate). There's always a chance of some taphonomic distortion, but then the pubic bones and ischia are strange, too: the pubic bones are very long, not particularly thick anterior-posterior, and oriented not far from vertical, and the ischia are afterthoughts. If you compare to other titanosaur hips, like, say, Rapetosaurus, it's possible to see that there is precedent for the general configuration, but the lineage leading to Q. pintiquiniestra seems to have leaned hard into pressing things toward an extreme. (Was there some kind of advantage for movement? Or just evolutionary drift on characters that didn't do much one way or the other? For that matter, after 150 million years of sauropod hips, were there any new tricks under the sun, or had sauropod backsides gone about as far as they could go under the laws of physics and the evolutionary material available to work with? Hard-hitting questions you only get at Equatorial Minnesota!)
Mocho et al. ran two phylogenetic analyses and found Q. pintiquiniestra to be distantly related to the majority of European titanosaurs (Lirainosaurinae), but much closer to Opisthocoelicaudia skarzynskii and closer still to Abditosaurus kuehnei, another recently named Spanish titanosaur but from a different formation. Rather inconveniently, despite A. kuehnei having a similarly articulated to associated partial holotype comprising a significant chunk of the animal, there is not too much overlap with the type of Q. pintiquiniestra (an ilium, which has been mostly lost for A. kuehnei; a fibula; and parts of the anterior to middle dorsals). They don't seem to be the same thing, though. I tend to take titanosaur phylogenies as suggestions, but the implications are interesting: an endemic group of European titanosaurs was meeting arrivals from Asia toward the end of the Cretaceous. Also interesting is that Q. pintiquiniestra's aeolosaur-like caudals came without having any particularly close relationship with aeolosaurs.
References
Mocho, P., F. Escaso, F. Marcos-Fernández, A. Páramo, J. L. Sanz, D. Vidal, and F. Ortega. 2024. A Spanish saltasauroid titanosaur reveals Europe as a melting pot of endemic and immigrant sauropods in the Late Cretaceous. Communications Biology 7: 1016. doi: https://doi.org/10.1038/s42003-024-06653-0.
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