Macronaria

   Macronaria is composed of two main groups: Brachiosauridae and Titanosauria.  The brachiosaurids are linked together by unusually long forelimbs plus cervical verts without split neural spines, while the titanosaurians also have unsplit cervical neural spines, plus an enlarged sacrum (more verts added here increases strength to the hip) with another dorsal vert grafted on to give a total of six, teeth between the pegs of diplodocids and the spoons of the brachiosaurids in form, and distinctive tail verts cupped on the front end (procoelous).  Titanosaurians were once believed to be close relatives of the diplodocids, but this is now known to be highly unlikely.
    
<-- Macronaria
      |--Camarasaurus
      `--+--Europasaurus
           `--Titanosauriformes
                |-->Brachiosauridae
                `--Somphospondylii
                     `--+--Euhelopus
                          `-->Titanosauria
                               
Macronaria: A new macronarian skull is known from the late EK Cedar Mountain Formation of Utah, and several unnamed macronarians are known from the EK of Spain.  Macronarian remains, including a partial neural arch and fibula, are also known from the Bajocian (LJ) of India.
    Camarasauridae has long been named, but with a small membership (occasionally including Euhelopus and company, and/or Aragosaurus and Lourinhasaurus).  As possible camarasaurids beyond Camarasaurus are not particularly well-known, and those that have been added to analyses have not supported much of a Camarasauridae, there's not much reason to persist in giving them their own page or heading.  Traditionally, they are best represented by LJ remains from Laurasian continents, although future study may assign some of the poorly-known macronarians here.  Also traditionally (e.g. just Camarasaurus), they generally had U-shaped troughs splitting their neural spines, long arms relative to their legs, robust boxy skulls, and large teeth described as spoon-like.  They were very average in most aspects, and lack the fame of some of their contemporaries.  Camarasaurids appear to have had strongly upwardly-directed necks. 

Taxon or Taxa: Time/Place: Comments:
Camarasaurus: Cope, 1877 (including Cathetosaurus [Jensen, 1988]) C. supremus (type) Cope, 1877 (?including C. lentus [Marsh, 1889 {originally Morosaurus lentus}])   Kimmeridgian-early Tithonian (LJ) of Colorado, Utah, Wyoming, and New Mexico Camarasaurus as a whole was the most common Morrison Formation sauropod.  C. supremus was the largest and also latest species, known from over five partial skeletons and several skulls.  The trend of increasing size over time is seen also in Apatosaurus, Diplodocus, and possibly Allosaurus.
C. lentus was a small, common Camarasaurus species.  It is known from at least five skeletons with skulls, including two excellent juvenile specimens.  It was essentially the same as C. supremus except for size and possibly the age (possibly from somewhat older rocks).
C. grandis (Marsh, 1887 [originally Apatosaurus grandis]) Kimmeridgian (LJ) of Wyoming, Colorado, and Montana C. grandis was a common lower Morrison species of camarasaur, currently known from six partial skeletons and two skulls (and numerous other miscellaneous elements).
?C. lewisi (Jensen, 1988 [originally Cathetosaurus]) late Kimmeridgian (LJ) of Colorado First assigned to its own genus, this taxon instead appears to be a very old individual from a Camarasaurus species (although this may change).  It was at first reported by its describer that this sauropod was the only sauropod capable of rearing up on its hind legs.  Its ilium was angled up in an unusual fashion.
Europasaurus holgeri Mateus, Laven, and Knötschke vide Sander, Mateus, Laven, and Knötschke 2006 Kimmeridgian (LJ) of Germany This is a dwarf macronarian from what were the islands of Europe (well, probably just one particular island, given how speciation happens on islands).  It is known from 11 individuals of different ages and sizes (1.7-6.2 m long), and bone histology indicates that the large individuals were adults.  Much of the skeleton is known, including at least one gorgeous skull that looks a bit like Brachiosaurus with a shorter snout and taller nasal arch (I got to see photos in a poster back at SVP 2004).
This makes another case of island dwarfism among dinosaurs, the most famous being Magyarosaurus. 

Macronaria i.s.: 

Taxon or Taxa: Time/Place: Comments:
Abrosaurus dongpoi Ouyang, 1989 Bathonian-Callovian (MJ) of China This sauropod is as yet rather obscure.  It had a Jobaria-like skull with an unusually high number of teeth, and some split neural spines.  Unfortunately, the tail is not known.
?Atlasaurus imelakei Monbaron, Russell, and Taquet, 1999 ?late Bathonian (MJ) of Morocco Based on a nearly complete skeleton originally referred to Cetiosaurus mogrebiensis, this animal may be a basal brachiosaurid close to Brachiosaurus's ancestry, or not a member of the Neosauropoda at all.
Janenschia robusta Wild, 1991 (originally Gigantosaurus robustus Fraas, 1908) Tithonian (LJ) of Tanzania Based on (as the species name suggests) some very robust limb bones and other pieces, this animal may have been a basal titanosaurian or related to Camarasaurus.  It was previously described as the earliest known "titanosaurid", because of some referred procoelous tail vertebrae, but more recent study indicates that the actual type material may or may not belong to a titanosaurian.  The main issue here is the tendency for this animal to change higher-level grouping with every analysis.
?Jobaria tiguidensis Sereno, Beck, Dutheil, Larsson, Lyon, Moussa, Sadleir, Sidor, Varricchio, G. Wilson, and J. Wilson, 1999 (?"Rebbachisaurus" tamesnensis) ?Hauterivian (EK) of Niger This recently-described sauropod is known from the remains of several individuals of differing age, including skulls in some cases, making it one of the most completely-known sauropods (living alongside is what may be an ankylosaurian, a first for Africa).  It appears to have either been a very basal macronarian, or more basal than Neosauropoda.  It had few specializations, unusual for such a late sauropod.

Titanosauriformes i.s.: A basal titanosauriform skull is know from the Cenomanian-Turonian (LK) of Argentina.

Taxon or Taxa: Time/Place: Comments:
Astrodon johnstoni Leidy, 1865 (Pleurocoelus) Aptian-Albian (EK) of Maryland, ?Texas, and Utah The Astrodon/Pleurocoelus saga is long and confusing.  Both were named from remains from the Arundel Formation of Maryland, Astrodon from teeth, Pleurocoelus nanus from vertebrae considered to be juvenile, and Pleurocoelus altus from remains thought to be the adult of the latter.  It now appears that only one sauropod is known from the Arundel, and Astrodon (sometimes seen as Astrodonius or Astrodon johnsoni; I'm not really sure what's going on with the alternate spelling) has priority.  The various remains indicate something like a brachiosaurid or basal titanosauriform.  Astrodon is also Maryland's state dinosaur.
Despite its loss, Pleurocoelus lives on in random EK fossils from North America, Europe, and Africa.  Remains from Texas referred to it include those of a very large animal, possibly something like Sauroposeidon, especially around the famous Glen Rose\Paluxy River trackways, where Acrocanthosaurus was probably its main predator.  This Texan material may actually belong to a basal titanosaurian, however (apparently not the same as Paluxysaurus).  Some Utah remains may belong to Cedarosaurus.  
Honestly, one could choose to employ just Pleurocoelus if one so desired, or both Astrodon and Pleurocoelus; I'm going to follow Carpenter and Tidwell's 2005 assessment. 
Baotianmansaurus henanensis Zhang X., Lü J., Xu L., Li J., Yang L.K., Hu W., Jia S., Ji Q., and Zhang C., 2009 LK of China Baotianmansaurus is another in what has become quite a parade: sauropods from the Cretaceous of China.  It hails from eastern China (Henan) and is known from fossils including dorsals.
Dongbeititan dongi Wang X., You H., Meng Q., Gao C., Chang X., and Liu J., 2007 EK of China Dongbeititan is the first named Jehol Group sauropod, and is known from a partial postcranial skeleton including girdle bones, verts, and limb bones.  It was described as a basal titanosauriform more derived than Euhelopus, Fusuisaurus, and Huangheititan, but less derived than Gobititan and Jiutaisaurus. 
Dongyangosaurus sinensis Lü J., Azuma, Chen R., Zheng W., and Jin X., 2008 early LK of China A titanosauriform, Dongyangosaurus is known from a partial postcranial skeleton.
Erketu ellisoni Ksepka and Norell, 2006 late EK of Mongolia Based on six very elongate cranial cervicals, a sternal plate, and a partial hind limb (tibia, fibula, astragalus, and calcaneum), Erketu was a long but not especially massive sauropod, probably something like Euhelopus.  The neural spines are split, and the known part of the neck appears to have been fairly straight.  Unexpanded cylindrical teeth may belong to it as well.
Fukuititan nipponensis Azuma and Shibata, 2010 EK of Japan Fukuititan is known from an incomplete skeleton that includes at least teeth, cervicals, arm bones, and pelvic bones.
Fusuisaurus zhaoi Mo, J., Wang, W., Huang, Z., Huang, X., and Xu, X., 2006 ?Aptian-?Albian (EK) of China Fusuisaurus may be the most basal known titanosauriform, and one of the largest EK sauropods (which puts it in decent Sauroposeidon\Isle of Wight company).  It is based on material including a left ilium and pubis, distal left femur, many ribs, and anterior caudals.
Huanghetitan: You, H., Li, D., Zhou, L., and Ji, Q., 2006  H. liujiaxiensis (type) You, H., Li, D., Zhou, L., and Ji, Q., 2006 EK of China Based on material including a scapulacoracoid and a sacrum, this new basal titanosauriform was a contemporary of the iguanodontian Lanzhousaurus.
H. ruyangensis Lu J., Xu, L., Zhang, X., Hu, W., Wu, Y., Jia, S., and Ji, Q., 2007 K of China H. ruyangensis is based on a partial skeleton including 6 sacrals, 10 caudals, and some ribs and chevrons.  Its claim to fame is having the deepest body cavity among dinosaurs, based on the ribs (one being about 2.93 m long).  
Lapparentosaurus madagascariensis Bonaparte, 1986 Bathonian (MJ) of Madagascar Based on juvenile remains once referred to Bothriospondylus, this taxon appears to be very close to, if not a direct ancestor of, Brachiosaurus.  It has been suggested that the formation in which it was found was actually LTr in age, which would be very interesting.
Malarguesaurus florenciae González-Riga, Previtera, and Pirrone, 2008 late Turonian-early Coniacian (LK) of Argentina Malarguesaurus is based on partial postcranial remains including caudals, chevrons, and partial humerus and femur.  Although the caudals had the standard titanosaurian procoelous fronts, the rear surfaces of the proximal and middle caudals were flat.  Malarguesaurus was a robust titanosauriform, and may have been closest to Phuwiangosaurus.
Pelorosaurus conybearei (?N.D.) Mantell, 1850 Berriasian-Valanginian (EK) of England Pelorosaurus is a fairly basic EK ?brachiosaurid, meaning it is somewhat smaller than its Jurassic counterparts, but overall pretty much the same.
"Cetiosaurus" brevis Owen, 1842, a chimera of iguanodont and possible Pelorosaurus material, may technically be the proper name for this taxon.
Ornithopsis hulkei (N.D.) Seeley, 1870 (?Pelorosaurus) Barremian (EK) of England Sometimes referred to Pelorosaurus, the material Ornithopsis is based on (two dorsals) is not good enough to be sure.
Tastavinsaurus sanzi Canudo, Royo-Torres, and Cuenca-Bescós, 2008 early Aptian (EK) of Spain Tastavinsaurus (name meaning "wine taster lizard" after the area it was discovered at) is known from a partial skeleton including a few dorsals and ribs, most of the right leg and part of the left, the pelvis, and twenty-five caudals.  It may be closest to Venenosaurus.
Venenosaurus dicrocei Tidwell, Carpenter, and Meyer, 2001 mid Aptian (EK) of Utah Similar to the earlier Yellow Cat member, Cedar Mountain Formation sauropod Cedarosaurus, this seemingly small basal titanosauriform, from the Poison Strip Member, is based on vertebral and limb remains.  Other material, including juvenile remains, may belong here.
Wintonotitan wattsi Hocknull, White, Tischler, Cook, Calleja, Sloan, and Elliott, 2009 latest Albian (EK) of Australia Wintonotitan was actually known for a long time (1974, to be precise); if you dig out your handy copy of Glut's The New Dinosaur Dictionary and flip to page 283, you'll see part of its holotype (a humerus).  It thus takes up part of the old "Austrosaurus" sp. material.  (Actually, it would be kind of fun to go through that whole end section of the book and figure out what all of the rumors were described as being; a couple are still out there.  But I digress).  The type material is mostly forelimbs and vertebrae, with some of the girdle bones.  When compared to its contemporary Diamantinasaurus, it comes out as having more elongate, less heavily-built bones.

Somphospondylii:

Taxon or Taxa: Time/Place: Comments:
Euhelopus zdanskyi Romer, 1956 (originally Helopus zdanskyi Wiman, 1929) ?Barremian-?Aptian (EK) of China (the age is a bit fuzzy, and was traditionally reported as LJ) This used to be one of the more familiar euhelopodids.  It is known from a partial skeleton and skull, plus very long arm and shoulder material.  Sometimes it's found with the Eusauropoda, but usually it's near the base of Titanosauria in something called Somphospondylii.  Erketu may be closely related.

 

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