Hadrosaurinae

   Known informally as the "flat-headed duckbills" (a misnomer, since it will quickly become clear that most "flat-heads" possess cranial ornamentation of some sort), hadrosaurines could be better defined as lacking hollow crests.  Unlike the lambeosaurines, hadrosaurines are known from good remains to have existed at the very end of the Mesozoic.
    Hadrosaurines may sort into several general groups, although the exact composition of these groups is uncertain (people have been largely leaving hadrosaurine phylogeny alone except for review articles and the occasional description of a new taxon, which is a shame given so much good material; results may vary).  Given this, you're going to get two versions, and I'm just going to throw all the valid hadrosaurines together in one table, by alphabetical order no less.  Even Lophorhothon.  And the incertae sedis genera.

<--Hadrosaurinae
      |--Lophorhothon
      `--+--"Saurolophini"
           |     |--"Kritosaurus" australis
           |     |--Kritosaurus
           |     `--Saurolophus      
           `--+--Prosaurolophus
                `--+--Gryposaurus
                     `--+--Edmontosaurus
                          `--"Maiasaurini"
                                |--Brachylophosaurus
                                `--Maiasaura

or, if you prefer:

<--Hadrosaurinae
      |--Lophorhothon
      `--+--+--Edmontosaurus
           |    `--+--Prosaurolophus
           |         `--Saurolophus
           `--+--Kritosaurus
                `--+--Gryposaurus
                     `--+--Brachylophosaurus
                          `--Maiasaura
Hadrosaurinae: The "gryposaurinids" (essentially Gryposaurus at this point) are known for their arched, flattened nasal regions, giving them a bulbous nose area in lateral view.  It has been suggested that they may have used their nasal arches in nudging contests.  An essentially complete skeleton of a "gryposaurinid", informally dubbed "Antonio," is known from Italy.  
    The "edmontosaurinids" (just Edmontosaurus at this point) include the only truly flat-headed hadrosaurines, with expanded beaks and little bony cranial ornamentation.  The " saurolophinids" are known for possessing a nasal crest without a gryposaur-like arch, sometimes forming a long spine that may have supported a skin sail, and sometimes forming small pyramidal shapes.  As with other hadrosaurids, it has been suggested fleshy air sacs ran along the expanded nasal depressions, that could be inflated for display.  The "maiasaurinids" had a unique broad, solid crest on the head.

Taxon or Taxa: Time\Place: Comments:
Brachylophosaurus canadensis Sternberg, 1953 (including B. goodwini Horner, 1988) middle middle Campanian (LK) of Alberta and Montana An unusual and heretofore somewhat rare Judithian hadrosaurine, Brachylophosaurus had a broad, solid, slightly keeled but for the most part flat plate on top of the head, with a short, spine-like projection over the rear of the skull.  It has been suggested this reinforced skull roof was used in intraspecific (same-species) pushing contests.  A new, essentially complete skeleton of a subadult ("Leonardo") has been found, with preservation of soft elements.
When first discovered in 1936, what would become the type skull was thought to belong to a Gryposaurus-type animal, which isn't too far off the mark.  The snout is quite tall and compressed, like the latter's, but not arched.  
In addition to the distinctive skull, the forearms are unusually long for a hadrosaur.  Referred to the type species is B. goodwini, based on a skull with the typical brachylophosaur plate interrupted by a depression. 
Edmontosaurus: Lambe, 1917 (including Anatotitan Brett-Surman vide Chapman and Brett-Surman, 1990) E. regalis (type) Lambe, 1917 Maastrichtian (LK) of Alberta, Colorado, North and South Dakota, Montana, and Wyoming This was a very plain animal, for a hadrosaurine, but also one of the largest at 30 to 40 feet long.  It is fairly common, with remain belonging to at least a dozen individuals known.  With Triceratops, Edmontosaurus dominated the dinosaurian herbivores at the end of the Cretaceous in western North America.
E. annectens (Marsh, 1892 [originally Claosaurus]; including Thespesius edmontonensis [or edmontoni] Gilmore, 1924, and ?Thespesius saskatchewanensis Sternberg, 1926) late Maastrichtian (LK) of Alberta, Saskatchewan, Colorado, Montana, S. Dakota, and Wyoming Known for a while under the guise of Anatosaurus, this taxon may be the female of E. regalis, although the jury is still out on this.  
A skeleton bearing small theropod nibbling about the jaws, indicating a survived attack on the neck, is known, and Edmontosaurus in general appears to have taken a fair amount of abuse from theropods (see for example a tail bitten by a tyrannosaurid and later healed).
Thespesius saskatchewanensis, also known as Anatosaurus saskatchewanensis, is based on a small skull and partial skeleton, with a few others referred to it.  It doesn't get much press, usually just showing up in reviews as its own species without much comment.
?E. copei (Lull and Wright, 1942 [originally Anatosaurus]; ?including Trachodon longiceps Marsh, 1897) late Maastrichtian (LK) of Montana and South Dakota This species, better known as Anatotitan copei (better known before as one of the Anatosaurus species), is among the most duck-billed of the "duck-billed dinosaurs," with an amazingly long beak on an otherwise Edmontosaurus-like skull.  It is a rare Lancian dinosaur, with two good skeletons and skulls known for it.  It had slight knobs about the eyes, and was a large hadrosaurine.  
It could be a species of Edmontosaurus, but I'm lukewarm on putting it in one of the other established species.  Yeah, sure, I suppose both skulls *could* have been crushed the same way, but I'm not convinced.  Same genus, different species works fine for me, though.
Gryposaurus:  Lambe, 1914 G. notabilis (type) Lambe, 1914 late middle Campanian (LK) of Alberta Gryposaurus is very familiar under the name Kritosaurus notabilis.  For a long time Kritosaurus and Gryposaurus were considered to be the same genus, but since about 1990 it has become clear that the type material of Kritosaurus is not as diagnostic as one would prefer, based as it is on a fragmentary skull.  Gryposaurus, meanwhile, is based on much better remains.  Interestingly, it now appears that Kritosaurus may actually be a "saurolophinid", instead of a "gryposaurinid", illustrating the problems of establishing hadrosaurid taxa on material that is either missing or has an inadequately preserved skull.  Gryposaurus is a fairly common Judithian hadrosaurine.
G. incurvimanus is often listed as its own species, although I have my doubts.  It's pretty much the same thing as G. notabilis, except its humerus is more robust, the rest of it is more gracile, and its nasal arch is farther forward; however, the G. incurvimanus skull is also somewhat smaller than those of G. notabilis, and the nasal crests move backwards with age in Prosaurolophus, so I'm willing to suggest that's what's happening here.  G. incurvimanus is based on a nice skeleton with scale impressions.
G. monumentensis is based on a skull and a good chunk of the skeleton with skin impressions, and is a more robust species.  There may also be a gracile gryposaur in the same Kaiparowits beds.
G. incurvimanus (Parks, 1920 (originally Kritosaurus) late middle Campanian (LK) of Alberta
G. latidens Horner, 1992 late Santonian-early Campanian (LK) of Montana
G. monumentensis Gates and Sampson, 2007 late Campanian (LK) of Utah
Hadrosaurus foulkii (N.D.) Leidy, 1858 early-middle Campanian (LK) of New Jersey Sadly, this historically important genus is based on remains that do not include a good skull, a terrible problem for classification of hadrosaurids.  It is known from a partial postcranium (more would have been known if people had known about dinosaurs in the 1830s and had kept the bones together, but that's life), and traditionally it has been thought of as like Gryposaurus or Kritosaurus, although this cannot be established.  This was the first classic dinosaur to be known from a decent postcranium, and through the limb proportions showed early researchers that some dinosaurs were bipedal.
Kerberosaurus manakini Bolotsky and Godefroit, 2004 ?late Maastrichtian (LK) of Russia Another new LK hadrosaur from the far-eastern Amur region of Russia, Kerberosaurus is based on a braincase with referred remains that together make up much of a skull.  What is known of the nasal indicates no large Gryposaurus-style arch or other extreme ornamentation, but the animal itself appears to be closest to the "saurolophinids".
Kritosaurus: Brown, 1910 (including Anasazisaurus and Naashoibitosaurus, both Hunt and Lucas, 1993) K. navajovius (type) Brown, 1910 (including Naashoibitosaurus ostromi Hunt and Lucas, 1993) early late Campanian (LK) of New Mexico Sometimes featured in older dinosaur books as a hadrosaurine with a Gryposaurus-type nasal arch, this animal is based on a skull that does not preserve a complete nasal area and was originally restored in a flat manner.  Chunks of it show some sort of ornamentation, but at the time, Brown didn't know what to do with them, having only what would become Edmontosaurus annectens and copei to go on as skull models.  Indeed, people are still piecing bits onto the skull from the collected fragments.  It is often pictured with a Gryposaurus nasal arch because for several decades, it was thought to be the same thing as the much better known Canadian taxon.  It may have been closer to Saurolophus, and differs from Gryposaurus in age, location, and cranial details (although the new Utah material muddies the location waters; what we really need are a few good K. navajovius skulls with the adult crest).
Material from the earliest middle Campanian of Texas, including a skull and hand, may belong to a new species.  Material from Mexico indicates a species 20% larger than K. navajovius, around 11 m long.
In 1993, Hunt and Lucas took two skulls that Horner had just assigned to K. navajovius and gave them their own genera: Anasazisaurus and Naashoibitosaurus.  Both are largely based on skulls missing the lower jaw and beak (Naashoibitosaurus has some postcrania, too) with nasal crests that grossly are halfway between Prosaurolophus and Gryposaurus in form, sort of tabs between the eyes.  Naashobitosaurus, when given a new genus, was thought to be from much younger strata than Kritosaurus (which gave it its name), but this turned out to be incorrect; Anasazisaurus is known from slightly older rocks and its crest overhangs the eyes, like a little handle.
As far as I'm concerned, Naashoibitosaurus and Anasazisaurus are Kritosaurus, and the only reason to keep them apart is because the three skulls aren't as nice as one would prefer.  I'm willing to go with a separate species for Anasazisaurus, because it's somewhat older and has a distinctive crest, and the full crest of adult Kritosaurus navajovius is not known, but Naashoibitosaurus appears to be just an immature individual of the type species.
K. horneri (Hunt and Lucas, 1993 [originally Anasazisaurus])
"Kritosaurus" australis Bonaparte, Franchi, Powell, and Sepulveda, 1984 late Campanian-early Maastrichtian (LK) of Argentina "Kritosaurus" australis is a rare Southern Hemisphere hadrosaurid, possibly "gryposaurinid" in affinity.  It is known from material belonging to about five individuals, including skull material.
Lophorhothon atopus Langston, 1960 Campanian (LK) of Alabama and North Carolina A rare Southeastern iguanodontian (heck, rare Southeastern dinosaur!), Lophorhothon is based on a partial skull and skeleton from a juvenile animal.  The skull has a small pyramidal crest between the eyes.  In the past, this animal was interpreted as a basal "saurolophinid", but new research has suggested both that it actually may be closer to Tenontosaurus, or that it is a basal hadrosaurine.
Maiasaura peeblesorum Horner and Makela, 1979 late middle Campanian (LK) of Montana Known from nesting colonies and copious skeletal remains found in the last quarter-century, Maiasaura has a short, broad projection somewhat akin to a shelf above the eyes.  It is known to have congregated in groups, possibly in numbers upward of 10,000 in some cases, and is famous for the care it appears to have given its young in the nest.  It is part of a distinctive subset of the Judithian fauna, from the Two Medicine Formation.
Studies of the young indicate a shift from bipedality to quadrupedality with age; this may hold true for hadrosaurids in general.
Prosaurolophus maximus Brown, 1916 (including P. blackfeetensis Horner, 1992) late middle Campanian (LK) of Alberta and Montana A somewhat nondescript large hadrosaurine, Prosaurolophus had a short pyramid between the eyes.  It is known from remains belonging to over 30 individuals of a variety of ages, including juveniles, and has been suggested as the ancestor of Saurolophus, hence the name.
P. blackfeetensis was differentiated from P. maximus by details of the nasal pertaining to crest size and extent of the depression around the nostril; essentially, it had a taller skull profile and bonebed remains.
Saurolophus: Brown, 1912 S. osborni (type) Brown, 1912 early Maastrichtian (LK) of Alberta A characteristic Edmontonian dinosaur, S. osborni is known from the remains of at least three individuals.  It had a prominent rear-facing spine between its eyes.
?S. angustirostris Rozhdestvensky, 1952 early Maastrichtian (LK) of Mongolia Usually considered solidly Saurolophus, this animal is one of the most common Nemegt dinosaurs.  Like S. osborni, there is a prominent rearward spine projecting from between the eyes.  Some workers have suggested that it belongs in its own genus, while others believe it could be the same as S. osborni.
Shantungosaurus giganteus Hu, 1973 (?Edmontosaurus) early-mid Maastrichtian (LK) of China Possibly the largest known ornithopod at around fifty feet (15 meters) in length and several tons in weight for an average adult, this animal is based on nearly complete skeletal remains from five individuals, which are said to differ from Edmontosaurus regalis mainly in size-related details, and so could be a species of Edmontosaurus.  It had an impressive fin-tail.
Wulagasaurus dongi Godefroit, Hai S., Yu T., and Lauters, 2008 Maastrichtian (LK) of China Wulagasaurus is a basal hadrosaurine known from isolated remains found in the Sahaliyania bonebed; such remains include partial upper and lower jaws, braincases, part of the pectoral and pelvic girdles, and humeri.  It was described as the basalmost hadrosaurine, which would suggest an Asian origin for Hadrosaurinae and Hadrosauridae.

 

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