diplodocoidea

 Diplodocoidea is a superfamily of sauropoddinosaurs, which included some of the longest animals of all time, including slender giants like Supersaurus, Diplodocus, Apatosaurus, and Amphicoelias. Most had very long necks and long, whip-like tails; however, one family (the dicraeosaurids) are the only known sauropods to have re-evolved a short neck, presumably an adaptation for feeding low to the ground. This adaptation was taken to the extreme in the highly specialized sauropod Brachytrachelopan. A study of snout shape and dental microwear in diplodocoids showed that the square snouts, large proportion of pits, and fine subparallel scratches in Apatosaurus, Diplodocus, Nigersaurus, and Rebbachisaurus suggest ground-height nonselective browsing; the narrow snouts of Dicraeosaurus, Suuwassea, and Tornieria and the coarse scratches and gouges on the teeth of Dicraeosaurus suggest mid-height selective browsing in those taxa.[2] This taxon is also noteworthy because diplodocoid sauropods had the highest tooth replacement rates of any vertebrates, as exemplified by Nigersaurus, which had new teeth erupting every 30 days.[3]

Diplodocoidea
Temporal range: Middle JurassicLate Cretaceous174–93 Ma 
PreꞒ
O
S
D
C
P
T
J
K
Pg
N
Possible Turonian Record [1]
Skeletons of Apatosaurus and Diplodocus
Holotype skeletons of Diplodocus carnegii and Apatosaurus louisaeCarnegie Museum of Natural History
Scientific classificatione
Kingdom:Animalia
Phylum:Chordata
Clade:Dinosauria
Clade:Saurischia
Clade:Sauropodomorpha
Clade:Sauropoda
Clade:Neosauropoda
Superfamily:Diplodocoidea
Marsh, 1884 vide Upchurch, 1995
Type species
Diplodocus longus
Marsh, 1878
Subgroups
  • Haplocanthosaurus
  • Diplodocimorpha
Synonyms
  • Rebbachisauroidea 
    Bonaparte, 1997

TaxonomyEdit

The below taxonomy follows the study of Emanuel Tschopp, Octavio Mateus and Roger Benson, 2015:[4]

  • Diplodocoidea
    • Haplocanthosaurus
    • Diplodocimorpha
      • Rebbachisauridae
      • Flagellicaudata
        • Dicraeosauridae
        • Diplodocidae
          • Amphicoelias
          • Apatosaurinae
          • Diplodocinae

The phylogenetics of Diplodocoidea were reviewed in 2015 with a specimen-level phylogenetic analysis, as well as a species-level analysis. Their cladistic analysis is shown below.[4]

Diplodocoidea

Haplocanthosaurus priscus  

Diplodocimorpha
Rebbachisauridae

Zapalasaurus bonapartei

Limaysaurinae

Cathartesaura anaerobica

Limaysaurus tessonei

Nigersaurinae

Nigersaurus taqueti  

Demandasaurus darwini

Flagellicaudata
Dicraeosauridae

Dyslocosaurus polyonychius

Suuwassea emilieae

Dystrophaeus viaemalae

Brachytrachelopan mesai  

Amargasaurus cazaui Amargasaurus NT small (mirrored).jpg

Dicraeosaurus hansemanniDicraeosaurus hansemanni22 flipped.jpg

Diplodocidae

Amphicoelias altus

Apatosaurinae

?Apatosaurinae gen. et sp. nov.

Apatosaurus ajax Apatosaurus Silhouette.svg

Apatosaurus louisae Apatosaurus louisae by durbed flipped.jpg

Brontosaurus excelsus Brontosaurus by Tom Parker.png

Brontosaurus yahnahpin

Brontosaurus parvus Apatosaurus Clean.png

Diplodocinae

?Diplodocinae gen. et sp. nov.

Tornieria africana

Supersaurus lourinhanensis

Supersaurus vivianae Supersaurus dinosaur.png

Leinkupal laticauda

Galeamopus hayi

Diplodocus carnegiei Diplodocus carnegii flipped.jpg

Diplodocus hallorum

Kaatedocus siberi

Barosaurus lentus