Pronunciation: bo-nuh-par-toh-ni-kuss
Meaning: Bonaparte's claw
Author/s: Agnolin et al. (2012)
Synonyms: None known
First Discovery: Río Negro, Argentina
Discovery Chart Position: #807
Bonapartenykus ultimus
Old Father Time was a little unkind to the remains of Bonapartenykus. But its skull-less, damaged, badly weathered and barely recognisable bones were no match for the sleuthing skills of Federico Agnolin and chums who quickly realised that they belonged to the youngest but largest known member of Alvarezsauridae: the oh-so-weird branch of coelurosaurian theropod dinosaurs that were diddy of size, long-jawed, small-toothed and probably feathered, and had short but stout arms that may have been used for mauling termite mounds.
Unique amongst alvarezsaurids in actually having arms of a semi-respectable length, Bonapartenykus is in some ways similar, superficially, to the South American flightless bird called Nandu and is roughly the same size. But its closest relative is fellow Pategonian alvarezsaur Patagonykus, and the pair now form a raised for-the-occasion family (Patagonykinae) that houses the latest living alvarezsaurs most closely related to modern birds.
The paper in which Bonapartenykus was described also heralded Arraigadoolithus patagoniensis, the name (known as an "ootaxon") given to a couple of smashed, fungus-riddled eggs and some bits of shell that were discovered less than a foot away from the holotype skeleton which, the authors claim, "allow us to determine the method of reproduction used by these creatures". Embryo-less and lacking fossilised evidence to suggest they were from a nest, speculation is rife that the eggs may have been inside the dinosaur when it died, though it isn't exactly clear if they had been eaten or were in production. Alternatively, they might not belong to Bonapartenykus at all, and bones and eggs could have simply been brought together by a swirling current during a flash flood, like a sort of Late Cretaceous omelette.
As an early but unplanned Christmas present to the media, Bonapartenykus was first mentioned in a manuscript that was "leaked" online in December 2011, long before the authors had intended. You may think this is no big deal, but it's actually a serious faux pas, and the guardians of the unwritten rules wound themselves up something chronic because, apparently, the jewels of the land must not be gazed upon by the tax-paying public's mortal eyes until they are given permission to do so. Whoopsie daisy.
Unique amongst alvarezsaurids in actually having arms of a semi-respectable length, Bonapartenykus is in some ways similar, superficially, to the South American flightless bird called Nandu and is roughly the same size. But its closest relative is fellow Pategonian alvarezsaur Patagonykus, and the pair now form a raised for-the-occasion family (Patagonykinae) that houses the latest living alvarezsaurs most closely related to modern birds.
The paper in which Bonapartenykus was described also heralded Arraigadoolithus patagoniensis, the name (known as an "ootaxon") given to a couple of smashed, fungus-riddled eggs and some bits of shell that were discovered less than a foot away from the holotype skeleton which, the authors claim, "allow us to determine the method of reproduction used by these creatures". Embryo-less and lacking fossilised evidence to suggest they were from a nest, speculation is rife that the eggs may have been inside the dinosaur when it died, though it isn't exactly clear if they had been eaten or were in production. Alternatively, they might not belong to Bonapartenykus at all, and bones and eggs could have simply been brought together by a swirling current during a flash flood, like a sort of Late Cretaceous omelette.
As an early but unplanned Christmas present to the media, Bonapartenykus was first mentioned in a manuscript that was "leaked" online in December 2011, long before the authors had intended. You may think this is no big deal, but it's actually a serious faux pas, and the guardians of the unwritten rules wound themselves up something chronic because, apparently, the jewels of the land must not be gazed upon by the tax-paying public's mortal eyes until they are given permission to do so. Whoopsie daisy.
(Latest Bonaparte claw )
Etymology
Bonapartenykus is derived from the surname of the great Argentinian palaeontologist Jose F. Bonaparte and the Latin word "onykus" (claw). The species epithet, ultimus (Latin for "latest"), was chosen because Bonapartenykus represents the youngest alvarezsaurid from South America.
Discovery
The remains of Bonapartenykus were discovered in the Allen Formation at Salitral Ojo de Agua, Río Negro Province, north-western Patagonia, Argentina.
The holotype (MPCA, 1290) is a partial and poorly preserved skeleton consisting of an incomplete vertebra from the back and material from the shoulder, left leg and hip. Two incomplete eggs and bits of smashed shell were found nearby though whether Bonapartenykus was mothering or plundering them may never be known.
